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Annual MeetingMarch 20-22, 2011Marriott RivercenterSan Antonio, TXAM-11-35 Twenty Questions:Identify Probable Cause of High FCCCatalyst LossPresented By:Phillip K. NiccumDirector – FCCTechnologyKellogg Brown & RootLLCHouston, Texas, USAN ational Petrochemical & Refiners Association 1667 K Street, NWSuite 700202.457.0480 voice 202.457.0486 faxThis paper has been reproduced for the author or authors as a courtesy by the National Petrochemical & Refiners Association. Publication of this paper does not signify that the contents necessarily reflect the opinions of the NPRA, its officers, directors, members, or staff. Requests for authorization to quote or use the contents should be addressed directly to the author(s)Twenty Questions:Identify Probable CauseofHigh FCC Catalyst LossPhillip K. NiccumDirector – FCC TechnologyKellogg Brown & Root LLCHouston, Texas, USAAbstractFluid catalytic cracking unit performanceand reliability are primary drivers of refineryeconomics. The containment of the finelypowdered catalyst within the circulatingFCC unit inventory is a critical element ofeffective FCC operation. Identifying theprobable causes of high catalyst loss from afluid catalytic cracking unit remains one ofthe more important yet esoteric challengesthat can be faced by FCC operators andengineers. The answers to twenty keyquestions provide a basis to list the morelikely causes of high losses. Armed with alisting of the most likely causes, a refinercan develop cost effective mitigation strate-gies to relieve if not solve the problem on-line or be prepared to confirm and correctthe situation during the next unit shut-down.This can prevent chasing unlikely solutions,while the real culprits escape detection.Figure 1 – Where Has the Cat Gone?IntroductionFluid catalytic cracking unit performance and reliability are pri-mary drivers of refinery economics. The containment of the fine-ly powdered catalyst within the circulating FCC unit inventory is critical for effective FCC operation. It is remarkable that two-stage reactor and regenerator cyclones as depicted in Figure 2 typically capture more than 99.997% of the catalyst dust en-trained with the product and flue gas vapors. Any significant loss in the ability to contain the catalyst will have serious nega-tive economic consequences such as those listed below. • Catalyst contamination of the slurry oil product reducing its value in the marketplace • Severe erosion of slurry circulation pumps• Required cleaning of heavy oil tanks due to catalyst build-up • Loss of compliance with permitted atmospheric particu-late emissions • Premature failure of flue gas power recovery turbines • Loss of catalyst fluidity; causes irregular or unstable cata-lyst circulation leading to lower FCC unit throughput and less desirable product yields • Several fold increase in fresh catalyst make up costs After a refinery notices an increase in FCC catalyst loss rate, an unfortunate scenario can start with a premature conclusion that the high loss rate must be due to mechanical problems that can only be cured by a unit shut-down and repairs. This scenario can then deepen when no obvious mechanical damage is found during a shutdown and it becomes apparent that the root cause of the losses can only be diagnosed by gathering clues and studying unit operations while the FCC unit is in service. In-deed, the worst thing that can be found during the shutdown and inspection could be finding nothing at all.Figure 2Orthoflow™ FCCUThere are many questions that can be asked when gatheringclues to determine the most likely cause of high FCC catalyst losses. These questions can be grouped into three categories.9 Questions with answers at your fingertips9 Questions that should have readily available answers9 Questions whose answers require data or analysis beyond that considered routine The above groupings can provide an order to an investigation, starting with the questions where answers are most easily available, and working down the list toward those requiring more time and cost to answer.Another complicating factor in FCC catalyst loss investigations, like many troubleshooting exercises, is that some of the supposed evidence may be corrupt or just plain wrong. It is up to the investigator to look for what is being indicated by the preponderance of a body of evidence, and not be drawn into making premature conclusions based on limited data. First Things First (Questions 1 -7)If the increased rate of catalyst loss is not severe, the first indication may be the report of higher than expected fresh catalyst additions needed to maintain the unit catalyst inventory. The first order of business is to ascertain which side of the reactor-regenerator system, if not both sides, is responsi-ble for the increased cata-lyst loss.Q1: What is the relativerate of catalyst loss in thefractionator bottoms com-pared to normal? loss rate through the reac-tor cyclones is normally astraightforward multiplica-tion of the slurry oil produc-tion rate times the concen-tration of ash in the slurry oil product. Q2: What is the relative stack opacity or rate offines catch compared tonormal?An increase in regeneratorindicates an increase in stack catalyst emissions.It is noted that particles with diameters greater than a few microns generally have an in-creasingly smaller impact on opacity while those with diameters in the range of 0.1 to 1.0 microns have the larger impact on opacity 1,2. The presence of third stage separators, elec-trostatic precipitators and flue gas scrubbers can obscure the impact of increased regene-rator catalyst losses on stack opacity 3.A concept referred to again and again in this paper is “what is normal?” Unfortunately, in many cases, this “normal” data may be difficult to obtain as the incentive to document prob-lems often gets more priority than collecting data concerning what things look like when all is well.It is also noteworthy if either the reactor or regenerator loss rate has decreased while losses from the other vessel have increased. With a constant rate of fines input (fresh catalyst) and fines generation by attrition, anything that reduces the fines losses from one vessel will increase the fines concentration in the unit and result in a corresponding in-crease in fines flow rate from the other vessel. For instance, commissioning a catalyst slur-ry oil filter with recycle back to the riser will increase the loss rate from a regenerator.Q3: What is the relative amount of equilibrium catalyst in the 0-40 micron range?An equilibrium catalyst data sheet provides a long term accounting of many important equi-librium catalyst properties that are useful in diagnosing catalyst loss issues. Chief among these is the particle size data4.The relative amount of fines in the catalyst inventory is often indicated by the percentage of the catalyst particles having a diameter less than 40 microns. This parameter provides an indication of whether or not the increased loss rate is due to cyclone malfunction versus an increase in fines generation due to increased attrition or a higher loading of fines with the fresh catalyst.Q4: What is the average equilibrium catalyst APS compared to normal?The change in average particle size (APS) of the equilibrium catalyst generally moves op-posite the fraction of fines in the catalyst. However, APS can also increase over time due to decreasing equilibrium catalyst withdrawals that traps the largest particles within the cir-culating catalyst inventory.Q5: How does the volumetric flow rate of reactor product vapors through the cyclones com-pare to normal?The volumetric rate of vapor flowing through the reactor cyclones can be estimated based on the reactor operating temperature and pressure together with the hydrocarbon product rate, reactor and stripper steam rates, and an estimate of the hydrocarbon product molecu-lar weight. The rates and molecular weights of any hydrocarbon recycle streams should also be included in the calculations.Q6: How does the volumetric flow rate of air or flue gas through the regenerator compare to normal?The regenerator air rate together with the regenerator operating temperature and pressure provide an indication of the volumetric vapor traffic through the regenerator and its cyclone system. Even better accuracy can be obtained by calculating the molar rate of the flue gas based on the air rate and flue gas composition.Q7: How does the catalyst circulation rate compare to normal?The most common method of estimating the catalyst circulation rate is based on the rege-nerator air rate, flue gas analysis and reactor and regenerator temperatures. For the pur-pose of catalyst loss troubleshooting, consistency of method is more important than the ab-solute accuracy of the method.The Next Level of Questions Require Legwork (Questions 8 – 13)Q8: What is the relative rate of catalyst loss from the regenerator compared to normal? On the regenerator side, quantification of the catalyst loss rate is best determined over a period of time by subtracting the reactor catalyst loss rate from the catalyst addition rate. Careful attention to changes in the unit and catalyst hopper inventories over the same time period is important for the catalyst balance.As mentioned previously, the presence of particulate capture devices downstream of the regenerator may obscure the impact of increased regenerator catalyst losses on stack opacity. In these cases, the investigator can review the catalyst catch rate in the post-regenerator flue gas clean-up equipment. For instance, data on the catch rate in a fourth stage cyclone fines hopper or electrostatic precipitator (ESP) dust bins can provide more evidence of increased re-generator catalyst loss.Q9: How does the freshcatalyst make-up ratecompare to normal?Documentation of catalystadditions is important forseveral reasons. Firstly,after accounting for anychanges in routine equili-brium catalyst withdrawalcatalyst additions to main-tain unit inventory corro-borates other indicationslosses. Secondly, increasing fresh catalyst addition rate, in and of itself, generally leads to increased losses due to increased fines input with the fresh catalyst and because the newer catalyst may have surfaces that are more easily abraded5.Q10: Are the losses steady or intermittent?If the increased catalyst losses seem to come and go with time, that is an indication that the problem may be more related to operating conditions than mechanical damage. For in-stance, the diplegs may be operating close to a flooded condition, where changes in gas rate or catalyst loading drastically affect the cyclone efficiency. In a counter-example, if the increased loss rate is due to a hole in a plenum or cyclone outlet tube, then the losses are more likely continuous and increasing.Q11: When did you last change the type of fresh FCC catalyst?If the type of fresh catalyst has changed in a timeframe that could coincide with the in-creased catalyst losses, the catalyst itself becomes suspect. Similarly, the same is true if the fresh catalyst receipts show significant physical property changes, especially in terms of the fraction of fines, density or Attrition Index6.Q12: When did the loss increase first occur?Q12: When did the loss increase first occur? It is also worthwhile to consider the date when the increased catalyst losses seemed to be-gin. Look for coincidences with other significant events in the FCC operation. For instance, did the time of the increased loss rate correspond with a unit turnaround or upset? Equip-ment damage is more likely to occur during a start-up, upset or shut down. Loss of restric-tion orifices that can cause an attrition prob-lem more commonly occurs during a turna-round. Were there other significant changes in the operation corresponding to the time of the increase in catalyst losses such as changes in feed rate, combustion air rate, catalyst circulation rate or feedstock quali-ty?Q13: How long did it take for the losses to Increase from a normal rate?If the catalyst loss rate made a step change from normal to a higher value, then that generally indicates the problem is not an erosion induced hole somewhere in the cyc-lone system; the hole size will increasegradually if erosion is to blame. Figure 3 – Microscopic View of FCC CatalystQuestions that may be Harder to Answer(Questions 14 -20) Most of the questions inthis grouping require some sample capture and/or la-boratory testing that would be considered non-routine.Q14: What is the relative angularity of the equili-brium catalyst?Looking at the sample ofloss under a microscopeas shown in Figure 3 can be very revealing. If thesample contains a lot ofsmall, jagged, or broken pieces, it indicates an ab-normally severe degree of catalyst attrition 7.Q15: What is the relative angularity of lost catalyst?Generally speaking, samples of the catalyst lost from the reactor are readily available from a sample of the slurry oil product or circulating slurry oil. The slurry oil can be washed and filtered in a laboratory, and the captured catalyst can be viewed under a microscope. If available, samples of catalyst lost from the regenerator can be viewed under a microscope. The microscope can reveal whether the sample contains a high concentration of small, jagged, or broken pieces indicating an abnormally severe degree of catalyst attrition.Q16: What is the relative APS of the catalyst in the reactor carryover?Catalyst taken from the slurry oil can be subjected to the all important particle size analysis. For a given rate of fines input and fines generation within the unit, material balance consid-erations dictate that the APS of the lost catalyst must increase as the loss rate increases. The image from the microscope can corroborate the particle size analysis by showing more than an expected fraction of larger particles and even very large particles that would never escape a properly functioning cyclone system.9If the average particle size (APS) of the lost catalyst is smaller than normal, and the loss rate is higher than normal, then that would indicate an increased degree of fines input or increased catalyst attrition.9Moderately increasing APS would indicate some loss of cyclone efficiency if the loss rate is higher than normal.9Moderately increasing APS would indicate a reduction in fines input or attrition if the loss rate is less than normal.9 A large increase in APS would indicate a major cyclone malfunction or serious dam-age.Q17: What is the shape of the differential particle size curve of the catalyst in the reactor carryover?The particle size analysis of a loss sample can also be reported as differential particle size distribution, indicating the fraction of particles falling in narrow size ranges. This is a differ-ent presentation than a cumulative particle size distribution displaying the weight percen-tage of particles having less than a given diameter8.Twenty Questions: Identify Probable Cause of High FCC Catalyst LossPARTICLE SIZE DISTRIBUTION0123456789100102030405060708090100PARTICLE SIZEP E R C E N TTypical PSDPoor Second Stage CyclonePerformanceFigure 4a -Reduced System Efficiency0123456789100102030405060708090100PARTICLE SIZEP E R C E N TAttrition0123456789100102030405060708090100P E R C E N THole or Crack in Outlet Tube or PlenumFigure 4b - Bi-Modal Distribution Indicating an Attrition ProblemFigure 4c - Bi-Modal Distribution IndicatingCyclone BypassThe shape of the differential particle size distribution curve can be insightful.9If the curve has only a single broad peak centered about a higher than normal par-ticle size as shown in Figure 4a, then this could indicate a partial loss of cyclone effi-ciency, but not complete bypassing of solids.9 A bimodal curve having a peak near that considered normal as well as a secondarypeak at a lower than normal particle size as shown in Figure 4b may indicate a cata-lyst attrition problem.9Some bypassing of material around the cyclones altogether would occur with a breached plenum chamber or hole in a secondary cyclone outlet tube as shown in Figure 4c. This curve has a peak near that considered normal as well as a second-ary peak at a higher than normal particle size.Q18: What is the relative APS of the catalysts in the regenerator carryover?The collection of a representative sample of catalyst lost from the regenerator is less straightforward than the collection of fines from slurry oil. Ideally, a dust sample can be col-lected from the regenerator effluent, and the results can be analyzed as previously dis-cussed with respect to catalyst separated from slurry oil. If dust collection equipment exists downstream of the regenerator, such as a scrubber, ESP or TSS, then the fines catch can also be analyzed and useful in the investigation.Q19: What is the shape of the differential particle size curve of the catalysts in the regene-rator carryover?If a dust sample from the regenerator effluent can be obtained, then the results can be ana-lyzed as previously discussed with respect to catalyst separated from slurry oil.Q20: How does the cyclone system pressure drop compare to normal?Some FCC units are instrumented with differential pressure measurements across vessel disengaging space and the vapor outlet. This provides an indication of the pressure drop though the cyclone system and it will indicate whether there has been a significant change in the catalyst or vapor loadings of the cyclones.Possible Causes of High FCC Catalyst LossesOnce answers to many of the 20 questions are available, these answers can be analyzed for fit with the characteristics of the problems described below to establish the more likely causes of the catalyst loss problem.Excessive Attrition in a Fluid BedCatalyst attrition in a fluid bed is caused by catalyst par-Array ticles colliding at high velocity with other particles or solidsurfaces. The high particle velocities in a fluid bed arechiefly the result of particle acceleration driven by highvelocity gas jets within the fluid bed. The focus of an in-vestigation into the source of excessive catalyst attritioncan include looking for the following types of problems:¾Missing restriction orifices or open orifice by-passes associated with pressure taps, torch oil nozzles, and other vessel connec-tions intended to pass only a small amount of gas, air or steam.¾ High velocity gas jets can also emanate from broken or eroded steam or air distribu-tors where gas escapes without traveling through a velocity reducing nozzle typically used in the design of such distributors.A high fines concentration in the lost catalyst, high fines content in the catalyst inventory and splintered, broken and jagged particles as viewed with a microscope, all are indicative of a catalyst attrition problem.Excessive Reactor or Regenerator Dilute Phase Attrition Excessive Reactor or Regenerator Dilute Phase Attrition Since there is little catalyst in a dilute phase, by definition, high attrition rates in this region are likely associated with particle impacts on solid surfaces within the cyclones, especially cyclones with high exit velocities.¾ The nature of the solid surfaces can also play a role in catalyst attrition with badlydamaged refractory or unusually rough refractory surfaces providing more opportu-nity for abrupt impact of the travelling catalyst.Plugged Reactor Secondary Cyclone DiplegSecondary cyclone dipleg plugging is much more common than the plugging of primary cyclone diplegs. The reason is smaller diameter diplegs. The plugging of a second stage reactor cyclone dipleg often calls for an immediate shutdown of the FCC unit due to high catalyst losses.¾ Coke can form in a reactor cyclone and then fall into the dipleg causing a full or par-tial plug 9.¾ If feed is introduced into the reactor before the internals are sufficiently heated, suchas can happen during start-up or upset, then large amounts of coke can appearwherever feedstock can condense.¾ Some cyclones have check valves on the dipleg.Anything that can cause the flapper to stick or beheld closed, including design problems or hingecoking will provide an effectively plugged dipleg.¾ Failures of the cyclone hexsteel attachments tothe cyclone interior shell can release sheets ofhexsteel and refractory sufficiently large to plugeven a large diameter diplegs. Such failures canbe attributed to poor hexsteel design or installa-tion as well as coke induced refractory anchorfailure 10.Plugged Reactor Primary Cyclone DiplegThe causes of primary reactor cyclone dipleg plugging are the same as given above for theplugging of reactor secondary cyclone diplegs.Plugging of reactor primary cyclone diplegs is relatively uncommon due to the large diplegdiameters normally associated with primary cyclones.If a primary cyclone dipleg does become plugged, then the catalyst loading to the second-ary cyclone may exceed the capacity of the secondary cyclone dipleg. In this event, thesecondary cyclone will become flooded with catalyst and full range catalyst will begin flow-ing at a high rate from the secondary cyclone outlet.Plugged Regenerator Cyclone DiplegsThe plugging of regenerator cyclone diplegs has sim-Array ilar causes and effects to those encountered with re-spect to the reactor cyclones, but plugging of rege-nerator cyclone diplegs is less common. In the re-generator, the coking phenomenon that is at the rootof most reactor cyclone plugging problems does notexist. However, there are some situations peculiar tothe regenerator cyclones.¾agents such as sodium, potassium, calcium ,introduced with contaminated feedstock, andespecially at high temperatures, the catalysttemperatures as low as 930 to 1200°F5. Athigher temperatures, the catalyst can fusetogether and prevent flow through the diplegs.¾secondary cyclone diplegs is that the almostextinct use of spray water in the regenerator primary cyclone outlets can lead to the formation of wet catalyst in the dipleg, preventing catalyst flow.¾Regenerator upsets, such as a sudden drop in pressure or the activation of emergency spent catalyst riser lift steam can precipitate a large catalyst carryover that may persist even after the disturbance is gone. This has been explained by noting that defluidized solids will drain from a cyclone much more slowly than flui-dized solids. So much catalyst can be thown into the cyclones that it defludizes before it can get into the dipleg. Then, even at normal entainment rates, the catalyst will not drain out of the cyclone fast enough to eliminate the packed catalyst level in the cyclone11.Holes in Plenum or Second Stage Cyclone Outlet TubeA hole in a plenum or secondary cyclone outlet tube as shown in Figure 5 provides a direct path for catalyst escape, bypassing the cyclone system, and allowing even large catalyst particles to show up in the main fractionator bottoms or flue gas system. Even a 10 mm hole can increase the catalyst losses several fold. In time, the passage of high velocitycatalyst through the hole will increase the hole size and the catalyst losses will intensify.¾ Holes often start as cracks or tears inthe metal, and in time they grow due tothe erosive effects of the catalyst flow.If the catalyst loss problem is not yetsevere, a unit inspection may have dif-ficulty finding the cracks as the cracksmay tend to close as the unit cools.¾ The impact of a hole in the outlet tubeor plenum of a reactor with Riser Cyc-lones will be less than with an inertialriser termination device because therewill be little catalyst in the dilute phasethat can be sucked into the hole.Holes in a Second Stage CycloneHoles in a secondary cyclone (or a singlestage cyclone), including holes in the cyclone dipleg will have serious consequences on catalyst containment. The rate of performancedeterioration will be controlled by how quickly the hole enlarges due to erosion. Holes in the dipleg allow the vapor flow into and up the dipleg. This can restrict the ability of catalyst to flow down the dipleg and even entrain catalyst up the dipleg. If the hole is in the cyclone body, then the incoming vapor jet can disrupt the desired vapor profile in the cyclone, da-maging the collection efficiency.Figure 5 – Two StageRegenerator Cyclone SystemHoles in First Stage CycloneHoles in primary cyclones are not as common due to the lower velocities in primary cyc-lones. The catalyst loss impact from a hole in a primary cyclone will be much less severe compared to a hole in a secondary cyclone, because the secondary cyclone will catch al-most all the catalyst lost from the primary cyclone. In fact, it may be difficult to even notice the increased catalyst loss associated with a hole in a primary cyclone.Stuck Open or Missing Flapper in First Stage Cyclone Stuck Open or Missing Flapper in First Stage Cyclone Most first stage cyclones are submerged in a fluid bedand do not have or need check valves because thecatalyst traffic is sufficiently high that gas does notforce itself up the dipleg. Sometimes check valves asshown in Figure 6 are included to limit losses duringstart-up when the diplegs are not submerged. In thesecases, a stuck-open flapper will be of little conse-quence during normal operations.In some cases, due to the unit geometry or tech-nical preference, the primary cyclones can be de-signed to discharge above the bed. In these cas-es, assuming the cyclone is not a positive pres-sure riser cyclone, a properly functioning valve isrequired. The consequences of a valve that isstuck open would be a major loss of cyclone effi-ciency, increasing the loading to the secondarycyclones and increasing the catalyst losses fromthe unit. Stuck Open or Missing Flapper in Second Stage CycloneA flapper stuck open or missing may not affect thecyclone performance if the dipleg is submergedsufficiently in a well-fluidized bed. If the bed fluidi-zation is erratic, then the losses may increase dueto unsteady catalyst flow down the dipleg or due togas bypassing up the dipleg.If the secondary cyclone dipleg is not submergedinto the fluid bed, a stuck open or missing flapperturns the dipleg into a vacuum tube sucking vaporsinto the cyclone; destroying the cyclone efficiency. A detached dipleg would have similar consequences.Figure 6 – Cyclone Dipleg Check ValveReactor Cyclone Overload (Excessive Dipleg Back-up / Insufficient Dipleg Diameter)A reactor cyclone system can become overloaded if thecatalyst or vapor traffic exceeds the design hydrauliccapability of the cyclone system. The cyclone systempressure drop increases with both catalyst and vaporloading. As the pressure drop increases, the catalyst inthe dipleg must back-up to a higher elevation as shownin Figure 7 to provide enough static head to force thecatalyst out of the dipleg. When the catalyst height inthe dipleg reaches the dipleg top, the swirling vapors inthe bottom of the cyclone will re-entrain the catalyst anddrastically reduce cyclone collection efficiency. Thissituation is referred to as “cyclone flooding”. Increasing。
大学英语四级模拟试卷721(题后含答案及解析)题型有：1. Writing 2. Reading Comprehension (Skimming and Scanning) 3. Listening Comprehension 4. Reading Comprehension (Reading in Depth) 5. Cloze 7. V ocabulary and Grammar 8. TranslationPart I Writing (30 minutes)1．For this part, you are allowed 30 minutes to write an essay entitled On Conserving Energy. You should write at least 120 words following the outline given below in Chinese: 1．能源短缺问题已经非常严重；2．可以采取节能措解决能源短缺问题；3．你的看法。
正确答案：Nowadays there is growing concern on the serious problem of energy shortage. Many people worry that energy resources on the earth will be exhausted if we use them in an unchecked way. And they believe that the energy shortage will cause serious problems and even crisis. Conserving energy is one of the measures which have been taken to solve the problem of energy shortage. For example, some countries have a daylight saving system to use less electricity for lighting. Also, some cities have enforced some facilities for saving water at public places such as rest rooms and bars. Still more, some have enforced serious penalties on overuse of electricity, water, and farming land. By these means, people hope the drain on energy resources could be slowed down. In a word, it is high time that serious consideration was given to conserving energy. Only through immediate and effective action, can we human beings survive and enjoy life as desired.解析：节能是当前备受关注的一个话题，因此可说的内容很多，紧紧围绕提纲要求进行阐述是本文的鲜明特点。
Investigation on the rate of reaction between gas (CO2) and liquor (NaOH) phases1 CHEN Bin(陈滨)，LI Xiao-bin（李小斌）*，LIU Gui-hua（刘桂华），PENG Zhi-hong（彭志宏），ZHOU Qiu-sheng（周秋生），XU Xiao-hui（徐晓辉），LIU Xiang-min（刘祥民）( School of Metallurgical Science and Engineering ,Central South University, Changsha 410083, P.R.China)Abstract：The neutralization of sodium hydroxide by carbon dioxide occurring during the process of carbonization precipitation of sodium aluminate solution was investigated. Firstly, the effects of those main factors such as CO2 concentration、temperature、initial concentration of NaOH were investigated. Then the kinetics equation concerning this reaction was obtained after proper data treatment. The results showed that it assumes an apparent activation energy of 8.06 kJ/mol which indicated a diffusion-controlled process. Furthermore, based on the principles governing diffusion-controlled process, the dependence of neutralization rate on gas flow was deduced theoretically with a form as: r d=KD K C A(Q/V L)2/3 whose plausibility was validated by those experimental research thereafter.Key words：reaction between gas & liquor phase；sodium hydroxide；carbon dioxide；diffusion control；kineticsCLC number: TF801 Document code: A1．INTRODUCTIONPresently in China, about 40% of alumina was produced by sintering process, where carbonization decomposition, that is, CO2 is ventilated into desilicated sodium aluminate solution to obtain Al(OH)3, holds a crucial procedure during alumina production[1]. Hitherto the mechanism of carbonization decomposition remains ambiguous for it’s a multiphase reaction involving series of complicated physicochemical processes such as crystallization, heat and mass transport, etc[2]. Thermodynamic and kinetic research[3,4] indicated that the essential of this process lies in the precipitation of Al(OH)3 resulting from the elevation of supersaturation with OH- being neutralized by CO2. So the ventilation profile of CO2 exerts a remarkable influence on the rate of the reaction and quality of the product. Generally speaking, it includes following steps: 1) transport of CO2 towards the gas-liquor phase interface; 2) chemical reaction between NaOH and CO2 at the interface; 3) removal of product from and transport of fresh reagents to the interface; 4) Mass transport relating to the production and growth of crystalline embryos on the seed surface[5].As described above, the neutralization of NaOH by CO2 holds a vital step during carbonization process. For the sake of controlling the process effectively, there’s every necessity to obtain the quantitative relationship between reaction rate and gas flow rate. However, related researches on this issue haven’t been reported so far. Though recently in consideration of the environmental protection which requires enterprises to reduce the emission of industrial gas resulting in greenhouse effect, the reaction behavior of CO2 in alkaline solution has been particularly studied[6-11], some influential factors such as air column height, configuration, gas pressure and interface area etc have been discussed at length and corresponding mathematical models established, yet the effect of gas flow rate was not singled out and what’s more, those systems were quite different from that of carbonization process.So a systematical study on the reaction process between CO2(g) and NaOH(L) was performed in this1Foundation item: Project (50274076) supported by the National Natural Science Foundation of China.* Correspondence: LI Xiao-bin, professor;. Tel: +86-731-8830454; E-mail: X.B.Li@.paper in the hope of realizing an effective control on carbonization and other similar processes.2．EXPERIMENTALDevices used in the experiments include a carbonizer as illustrated in Fig.1, a CYSE-II type O2/CO2 aerometer (XueLian meter company of Jia Ding, Shanghai), a thermostat with stirrer (Nanjing Timing electromotor Co., Ltd)and a LZB-6 type vitreous rotor flowmeter (Yuyao meter factory, Zhejiang).NaOH solution was prepared by dissolving chemical pure NaOH in distilled water and feeding gas by blending air and pure CO2. The carbonizer served as a cylindrical reactor with a diameter of 16.5cm and a height of 20cm where certain amount of solution was poured and feeding gas (air and CO2) continuously ventilated through the orbicular porous vent-pipe located in its bottom. CO2 concentration was measured with the CYSE-II type O2/CO2 aerometer and gas flow rate with the LZB-6 type vitreous rotor flowmeter. At controlled temperature and stirring speed, small amount of solution samples were taken at specified intervals for measuring the NaOH concentration with chemical titration method.1. Lift Tank;2.Electromotor;3. Pulleys;4. Reactor;5.Thermostatic oil bathFig.1 Schematic diagram of carbonizer3．RESULTS AND DISCUSSION3.1Establishment of the kinetics equation concerning CO2(g)—NaOH(L) reaction3.1.1 Influence of main factors on the reaction rateThe variation of NaOH concentration with reaction time at different experimental conditions was plotted in Fig.2～Fig.4, which shows the influence of CO2 concentration, temperature and initial NaOH concentration on the reaction rate respectively. Under all circumstances, the liquor’s volume is 2 liter. As shown in Fig.2 there’s a linear relationship between NaOH concentration and reaction time; that is, the time that NaOH is completely neutralized decreases with the raise of CO2 concentration, or to say, the reaction rate climbs up rapidly with the increase of CO2 concentration. While the influence of temperature is not remarkable as the four curves in Fig.3 are nearly overlapped within the temperature range of 75～95℃, the initial NaOH concentration either exerts little influence on the reaction rate as the three curves in Fig.4 are almost parallel. All these results are consistent well with those from literatures[12,13].Fig.2 Variation of NaOH concentration Fig.3 Variation of NaOH concentration with reaction time at different CO 2 concentrations with reaction time at different temperatures(temperature 85℃, flow rate 0.22Nm 3.h -1,(concentration of carbon dioxide 31%, flow rate stirring speed 250r.min -1)0.22Nm 3.h -1,stirring speed 250r.min -1)Fig.4 Variation of NaOH concentration with timeat different initial NaOH concentrations(temperature 85℃, flow rate 0.22 Nm 3.h -1, stirring speed 250 r.min -1, concentration of carbon dioxide 30%)3.1.2 Establishment of the kinetics equationThe reaction that NaOH solution is neutralized by CO 2 can be expressed as an equation as follows:2NaOH+CO 2=Na 2CO 3+H 2O (1)According to the principles of chemical kinetics [14], the kinetics equation of reaction (1) can be defined as:r=－τd NaOH dc )(=A )(RT Ea e − 221)()(n n CO c NaOH c (2)As discussed above, the influence of NaOH concentration on the reaction rate can be neglected in Eq.(2); Since the pressure of the system is 105 Pa as the feeding gas is ventilated into the unsealed reactor, the volume percent of CO 2 equals to its partial pressure according to Henry’s law on the premise that feeding gas meets the behavior characteristics of those idea ones at given temperature ；The ratio of CO 2 which participated in reaction to whole CO 2 can be calculated using the data in Fig.2～Fig.4, its value is in the range of 70～100% (The highest approached 98.7%). So we can consider that most of CO 2 was absorbed. Thus comes following equation:r=A )(RT Ea e −n CO )(2ϕ (3)Taking natural logarithm at both sides of Eq. (3) yields :)(ln ln ln 2CO n A r RT Eaϕ+−= (4)Where: r ―reaction rate ,mol.L -1.min -1； A ―preexponential factor ； Ea ―activationenergy ,J.mol -1；)(2CO ϕ―CO concentration ,%；τ―reaction time ,min ；R ―gas constant ,8.314 J.mol 2 -1.K -1；T ―temperature ，K 。
Photosynthesis Questions1.Write a balanced equation to summarise the process of photosynthesis.2.Explain the part played by NADP- in photosynthesis. the process that takes place in plants in which this energy is converted to a usableform. the gas used in photosynthesis. the gas produced during photosynthesis.6.Suggest one way in which the rate of photosynthesis of plants in a greenhouse could beincreased.7.Light energy trapped by chlorophyll is used to split water. List three products that resultwhen water is split.8.Carbon dioxide is essential for photosynthesis. Where does it enter the leaf?9.From your knowledge of photosynthesis suggest a way to increase the yield of plants such aslettuces in a greenhouse.10.What is the primary role of chlorophyll in photosynthesis?11.Write an equation to summarize photosynthesis.12.Why is the dark stage of photosynthesis given the alternative name of the light-independentstage? a gas that is essential for the dark stage of photosynthesis.14.Two products of the light stage of photosynthesis are vital for the dark stage. Name each ofthem. the structures in plant cells in which photosynthesis takes place.16.In addition to carbon dioxide another small molecule is needed for photosynthesis. Namethis other molecule.17.What happens to water molecules when they reach the sites of photosynthesis?18.State a precise role for each of the following in photosynthesis: (i) Carbon dioxide, (ii)Water. the process that converts the principal source of energy into chemical energy inplants.20.True or False : During photosynthesis oxygen is produced.21.From what substance is oxygen produced?22.In which stage of photosynthesis is oxygen produced?23.3. Give two possible fates of oxygen following its production.24.In photosynthesis water (H2O) is split into three products.1. Name these three products.2. State what happens to each of these products.25.In what main part of a plant does most photosynthesis take place?26.What do the letters ATP stand for?27.Energised electrons play a central role in ATP formation during photosynthesis. What is anenergised electron?28.ATP is an abbreviation. What does it stand for?29.In which of the stages of photosynthesis does ATP form?30.In which stage of photosynthesis does carbon dioxide provide carbon for carbohydrateformation?31.For what is ATP an abbreviation?32.What is the role of ATP in cells? the energy source for photosynthesis.34.Where in a cell does photosynthesis take place?35.Write a balanced equation for photosynthesis.36.What is the main source of light for photosynthesis?37.During photosynthesis water molecules are split into three products.1. Name each of these products.2. Describe what happens to each of the products.38.What is the relationship between the rate of photosynthesis and either the light intensity orthe carbon dioxide concentration.39.Most Irish tomatoes are grown in greenhouses. State two ways a commercial producercould increase her/his crop yield of tomatoes.40.The cells in the palisade layer contain many organelles that carry out photosynthesis.Suggest why the cells here contain more of these organelles than the cells in the spongy mesophyll.41.Where in a plant cell does photosynthesis take place?42.Give the alternative name of the first stage of photosynthesis.43.During the first stage of photosynthesis energised electrons enter two pathways. Where dothe energised electrons come from?44.In the second stage of photosynthesis compounds of the general formula C x(H2O)y areformed. What name is given to this group of compounds?45.From which simple compound does the plant obtain the H used to make compounds ofgeneral formula C x(H2O)y? the simple compound that supplies the necessary energy for the second stagereactions in photosynthesis.47.For which purpose did you use an aquatic plant such as pondweed rather than a terrestrialplant when investigating the rate of photosynthesis?48.What is meant by the term photosynthesis?49.A gas from the air is needed for photosynthesis. Name this gas. the part of a plant cell in which photosynthesis takes place.51.Write a balanced equation for photosynthesis.52.Plants contain the green pigment chlorophyll. What is the role of chlorophyll inphotosynthesis? any two environmental factors affecting photosynthesis that could be investigatedusing Elodea in water.54.How would you measure the rate of photosynthesis using the apparatus containing Elodeaand water?55.In your investigation on the rate of photosynthesis, the variable was either light intensity orCO2 concentration.I indicate clearly which factor you choose to address and answer the following questions:1. Suggest a suitable plant for such an investigation.2. How was the rate of photosynthesis measured?3. Name a factor that must be kept constant during this investigation.4. Explain how you would keep constant the factor referred to in 3.5. Why is it necessary to keep that factor constant?。
剑桥雅思真题英语听力下载剑桥雅思的真题听力材料，为雅思做准备。
下面是店铺给大家整理的下载剑桥雅思真题英语听力，供大家参阅!下载剑桥雅思真题英语听力1As we saw in the last lecture,在上一堂课我们已经看到了，a major cause of climate change is the rapid rise in the level of carbon dioxide in the atmosphere over the last century.导致气候变化的一个主要原因就是自上个世纪以来，大气中二氧化碳含量迅速增加。
If we could reduce the amount of CO2, perhaps the rate of climate change could also be slowed down.如果我们能减少CO2的含量，也许气候变化的速度就也能有所减缓。
One potential method involves enhancing the role of the soil that plants grow in, with regard to absorbing CO2.一个可能的措施是加强培育植物的土壤在吸收二氧化碳方面的作用。
Rattan Lal, a soil scientist from Ohio State University, in the USA,来自美国俄亥俄州立大学的土壤学家Rattan Lal声称，claims that the world's agricultural soils could potentially absorb 13 per cent of the carbon dioxide in the atmosphere 全世界的农业土壤可能一共能够吸收大气中百分之十三的二氧化碳，the equivalent of the amount released in the last 30 years.这一数字相当于过去三十年里释放的二氧化碳总量。
高二英语全球安全意识广阔单选题20题(答案解析)1.The increase in carbon dioxide emissions is mainly caused by_____.A.burning fossil fuelsing solar energyC.planting more treesD.reducing waste答案：A。
本题考查对全球环境问题的了解以及词汇辨析。
选项A“燃烧化石燃料”会释放大量二氧化碳，是二氧化碳排放增加的主要原因。
选项B“使用太阳能”是一种清洁能源，不会增加二氧化碳排放。
选项C“种植更多树木”有助于吸收二氧化碳，而不是增加排放。
选项D“减少浪费”与二氧化碳排放增加无关。
2.Climate change is likely to lead to_____.A.more stable weatherB.lower sea levelsC.extreme weather eventsD.decreased biodiversity答案：C。
本题考查对气候变化影响的认识。
选项A 气候变化会使天气更不稳定，而不是更稳定。
选项B 气候变化会导致海平面上升，而不是降低。
选项C 气候变化很可能会导致极端天气事件，如暴雨、干旱、飓风等。
选项D 虽然气候变化可能会影响生物多样性，但不是直接导致，没有选项C 直接。
3.One way to reduce environmental pollution is to_____.A.increase industrial productione disposable productsC.recycle waste materialsD.burn plastics答案：C。
本题考查环保措施。
选项A“增加工业生产”会加重环境污染。
选项B“使用一次性产品”会产生大量垃圾，加重污染。
选项C“回收废料”可以减少垃圾，降低环境污染。
选项D“燃烧塑料”会产生有害气体，加重污染。
1. Having practiced so many times, I feel very ________ of my ability to deliver the presentation successfully.A. confidentB. enthusiasticC. incredibleD. satisfied2. Smart phones – with cameras and color screens – can ________ images and data using wireless network technology.A. evolveB. departC. transmitD. assure3. Don’t take someone you get to know from the Internet to your house no matter how ________ he sounds.A. boldB. genuineC. flexibleD. available4. This kind of exercise will ________ your creativity, renew your energy, and unlock your potential.A. bindB. yieldC. embraceD. stimulate5. He makes his students ________ knowledge through various kinds of interesting activities.A. studyB. learnC. achieveD. acquire6. Politicians should not ________ in business affairs that might affect their political judgment.A. engageB. embraceC. departD. treasure7. I wish to ________ a master’s degree in electric engineering after I graduate from college.A. pledgeB. exploreC. pursueD. approach8. It was when I read his letter ________ I realized he had given me huge help.A. thatB. thenC. beforeD. after9. I believe friendship is an essential element of making a healthy, ________ life.A. flexibleB. rewardingC. wealthyD. inquisitive10. No other drugs are as good as this one; it must have been based on a(n) ________ formula (配方).A. enormousB. stimulatingC. uniqueD. overwhelming11. The investigation ________ evidence of a large-scale illegal trade in wild birds.A. uncoveredB. outweighedC. overwhelmedD. evolved12. Showing some sense of humor can be a(n) ________ way to deal with some stressful situations.A. genuineB. availableC. effectiveD. favorite13. It will be worth the efforts even if you fail; the rewards you ________ will be great.A. reapB. boastC. assureD. cultivate14. He doesn’t ________ of buying a house this year because the bank has refused to lend him any money.A. affordB. make the mostC. run outD. stand a chance15. Setting up separate bicycle tracks is an effective way to _______ bicycle accidents and improve the safety for riders who share the road with motor vehicles.A. curbB. clipC. surgeD. solve16. In the last two decades world production of electricity has roughly doubled, with the developing nations _______ the developed.A. surgingB. overtakingC. haulingD. reversing17. Language and culture are closely related with each other, and the understanding of one requires the understanding of _______.A. otherB. anotherC. the otherD. some other18. Joe is always wearing _______ shoes because his feet are in different sizes and he has to go toa special shoe store.A. worn-outB. softC. mismatchedD. polished19. Exercise should include nonstop activity performed for 30 or more minutes in order to keep the heart rate up. In other words, it should be done in a(n) ________ way.A. immenseB. irregularC. continuousD. routine20. The impact of culture shock can ________ from person to person. There can be significant differences because some people may be better prepared to enter a new culture.A. strainB. varyC. transmitD. benefit21. He hurried behind the other team members to get ________ their own bus.A. throughB. inC. upD. aboard22. Jane wanted to break up with her boyfriend, but she ________ herself at the last minute and decided to give it another try.A. regrettedB. overwhelmedC. strainedD. reversed23. Isaac Asimov was an American author and professor of biochemistry, best known for his works of science ________ and for his popular science books.A. figureB. foundationC. capacityD. fiction24. In terms of academic achievement, I was never a failure, and will definitely ________ in the future.A. make offB. make senseC. make itD. make upUnit325. Science can now ________ many things which were thought to be mysterious by ancient people.A. care forB. lay outC. account forD. set up参考答案： C26. Our hope for an enjoyable dinner was instantly ________ when the waiter dropped a salad plate on my head.A. spoiledB. restrictedC. explodedD. vanished参考答案： A27. Alice used to be terribly shy, but working abroad for a year has completely ________ her.A. solvedB. transformedC. characterizedD. regulated参考答案： B28. Take action on those things that will have the biggest ________ impact on your life with the least amount of effort.A. portableB. positiveC. sophisticatedD. moderate29. The adoption of this measure will greatly reduce the ________ of greenhouse gas emissions (排放物), which may help slow global warming.A. loanB. declineC. releaseD. response30. We regret for selling you the faulty product, and our company has agreed to ________ you by $500.A. matchB. reverseC. rewardD. compensate31. We are sorry to know that they did not succeed ________ the project for lack of necessary funds.A. to fulfillB. to have fulfilledC. in fulfillingD. with fulfilling参考答案: C32. It is surprising that fewer students were prepared to undertake the ________ to hand in written work on a regular basis, or to study over long periods.A. engagementB. commitmentC. authorityD. aspiration33. In 1988 the old system was ________ in the country and a new system was introduced to take effect in 1990.A. transmittedB. abolishedC. assumedD. compensated34. We should not ________ ourselves to the classroom. We should go out of the classroom, see the world and talk to others as much as we can.A. entertainB. confineC. assignD. involve35. My brother and I managed to ________ with each other and we soon made peace after a week’s quarrel.A. healB. reconcileC. respondD. advocate36. Because of his long illness, Lee’s English level had dropped, but he was determined to ________ the other students by working harder.A. put up withB. catch up withC. get along withD. fill up with37. We appreciate your efforts in making changes in your schedule and think that this new arrangement is now ________ to us.A. agreeableB. sustainableC. portableD. indispensable38. Almost half of that group will experience stress ________ enough to call for professional help.A. tenseB. moderateC. bearableD. intense参考答案: D39. Women have a greater ability to ________ names with faces than men do, and they are also better at recalling lists.A. associateB. compareC. engageD. involve40. The famous saying ________, “Where there is a will, there is a way.”A. saysB. goesC. tellsD. comes41. Even after his wife ________ he kept the little rose garden, as though she were still alive and still sitting at his side.A. got awayB. threw awayC. turned awayD. passed away42. Some people think greater foreign participation ________ China’s economy is inherently a good thing.A. withB. intoC. onD. in43. It is essential that you ________ up with your classmates in the last term of study.A. keepB. keptC. would keepD. have kept44. The direct cause of his illness is ________ smoking, but the real cause is his deep grief at his grandmother’s death.A. crucialB. excessiveC. generousD. exclusive45. It was ________ from the man’s body language that something horrible had happened or was going to happen.A. apparentB. appreciativeC. appearingD. applicable46. In British English today, little or no ________ is made between these two words.A. distinctionB. correctionC. similarityD. difference47. She held her son tenderly in her arms and ________ his hair, and said nothing until he was calm again.A. struckB. stuckC. strokedD. stacked48. Workers in this big firm received a(n) ________ part of their pay in the form of bonuses.A. inherentB. substantialC. invisibleD. subsequent49. They searched around for some nice little things to ________ their new apartment.A. furnishB. fillC. arrangeD. put50. ________ whether he is right or wrong, we have to obey his orders in the action.A. Despite ofB. Regardless ofC. DespiteD. Regardless51. With a good command of English, he soon got ________ to working with British people.A. accustomedB. consistentC. relevantD. responsible52. What needs to be ________ here is that language and culture interact, and that understanding of one requires understanding of the other.A. alteredB. stressedC. arousedD. committed53. Policies and organizations must be created to meet workers’ hopes, and to ________ new problems that inevitably arise between workers and managers.A. compromiseB. ensureC. undermineD. resolve54. To keep the wheels of industry turning, we produce consumer goods in endless quantities, and, in the process, are rapidly ________ our natural resources.A. ignoringB. collapsingC. enduringD. exhausting55. As a person who loves peace, he is committed ________ realizing peace between countries.A. ofB. aboutC. forD. to56. Learning how to use chopsticks is easy for me, ________ learning how to conduct myself at the table is quite difficult.A. whereasB. howeverC. thereforeD. besides57. Kenyan (肯尼亚的) women tend to vote for those who could provide them ________ the necessary food to live on.A. ofB. withC. forD. about58. In deciding whether or not a situation is safe, pilots must be taught to assume that the worst will happen, and then to ________ whether there is a risk or not.A. absorbB. applyC. assessD. occupy59. The worker was not worried as he knew that if he gave up the job, there would be ________ opportunities for him to work somewhere else.A. formativeB. marginalC. vigorousD. numerous60. The research shows the region might ________ overheating (经济过热), but the policymakers so far appear to be relatively relaxed about the future of the economy.A. catch a glimpse ofB. be at risk ofC. take a toll onD. be free from61. Measures have been taken to ensure that no student will have to ________ of college for economic reasons.A. lay outB. cancel outC. drop outD. stand out62. Stress that is not treated can lead to significant medical illnesses, which ________ can lead to greater stress and even depression (抑郁症).A. after allB. in turnC. on the contraryD. at least63. You shouldn’t ________ – let your children make their own decisions.A. interactB. abuseC. startleD. interfere64. Rising sales is a good ________ that this product is well received in the market.A. responseB. conventionC. indicationD. influence65. After ________ research by the local government, officials confidently stated that this area of the sea was much safer than before.A. extensiveB. durableC. extremeD. partial66. As the world is becoming global, it is increasingly important that countries work together to ________ international trade.A. soarB. promptC. riseD. facilitate。
GMAT备考：GMAT考试逻辑机经GMAT考试对同学们的逻辑分析能力提出了较高的要求，而这一点正是很多中国考生的弱势所在，下方为广大考生整理了GMAT考试逻辑机经，希望对各位了解GMAT考试，锻炼自己的逻辑分析能力有所帮助。
GMAT备考：GMAT考试逻辑机经1. 停车休息V1 daisychannie 有一道高速公路汽车司机应该开长时间车要休息但是很多司机不愿意休息说是因为给卡车的停车位少问weaken 我好像选的shopping mall里有很多停车位给卡车司机V2 LordVoldemort 逻辑只记得一题比较清楚，法律规定高速公路上司机超过10小时驾驶要休息一会，但是public停车位置不够，因此认为这项法律不能很好的执行。
问削弱。
答案有，有，很多服务区也提供了休息的位置;某个地方休息的位置比以前大Hutonian Government Official: Federal law requires truck drivers to take a long break after driving for ten hours, but truck drivers frequently do not comply. Since the public rest areas along our highways cannot accommodate all the drivers needing a break, we plan to build more rest areas to increase the rate of compliance.Hutonian Business Representative: But if the parking lots around our businesses are considered, there are more than enough parking places.Which of the following, if true about Hutonia, would provide a reason for persisting with the government official's plan despite the objection?(A) Public parking areas are evenly distributed along the highways.(B) Truck drivers are most likely not to comply with the federal law if the total time required for a trip exceeds ten hours by less than an hour.(C) In comparison to public rest areas, private parking lots near highways tend to be time-consuming for drivers to reach.(D) Even when rest areas are available, some truck drivers park in places, such as highway access ramps, where their trucks are likely to cause accidents.(E) Some public parking areas, particularly those on heavily traveled roads, are substantially larger than others.答案：C考古96、征服规定司机休息政府规定司机要开8小时车休息十小时但是司机说parking places太少了问削弱我选的其实很多什么商店提供了很多的parking places37. 【长途汽车】一个地方的准备制定一项法律规定当地长途车司机每开10小时要休息8小时。
Introduction:The purpose of this experimental report is to outline the objectives of the experiment conducted. The experiment was designed to investigate the effects of various factors on the outcome of a specific process or phenomenon. The report aims to provide a comprehensive understanding of the experiment's goals, the methodology employed, and the expected outcomes. This report will be structured into several sections,including the background, objectives, methodology, results, and conclusions.I. BackgroundThe background section provides an overview of the experiment's context, including the significance of the study and the rationale behind conducting the experiment. It also discusses the existing literature and any previous research that may have influenced the experimental design.In the current study, the experiment was focused on the investigation of the effects of temperature and pressure on the rate of a chemical reaction. The experiment was motivated by the need to understand how environmental conditions can influence the kinetics of chemical reactions, which is crucial in various industrial processes and biological systems.II. ObjectivesThe objectives of the experiment are as follows:1. To determine the effect of temperature on the rate of the chemical reaction.2. To determine the effect of pressure on the rate of the chemical reaction.3. To establish the relationship between temperature and pressure in terms of their influence on the rate of the chemical reaction.4. To compare the experimental results with theoretical predictions based on established kinetic models.5. To identify the optimal conditions for the chemical reaction under investigation.III. MethodologyThe methodology section describes the experimental setup, materials, and procedures used to achieve the objectives outlined above.A. Experimental SetupThe experiment was conducted using a custom-built reaction chamber equipped with temperature and pressure control systems. The reaction chamber was designed to allow for precise control of the temperature and pressure during the experiment.B. MaterialsThe materials used in the experiment included a solid reactant, a liquid reactant, a catalyst, and a suitable solvent. The purity and concentration of the reactants were carefully chosen to minimize the influence of other factors on the results.C. Procedures1. Temperature Effect: The reaction was conducted at different temperatures, ranging from 25°C to 100°C, with an interval of 25°C. The reaction rate was measured by monitoring the change in the concentration of the reaction product over time.2. Pressure Effect: The reaction was conducted at different pressures, ranging from 1 atm to 5 atm, with an interval of 1 atm. The reaction rate was measured in the same manner as described for the temperature effect.3. Comparative Analysis: The experimental results were compared with theoretical predictions based on established kinetic models, such as the Arrhenius equation and the rate equation derived from the reaction mechanism.IV. ResultsThe results of the experiment are presented in the form of graphs and tables, showing the relationship between temperature, pressure, and the rate of the chemical reaction. The data obtained were analyzed using statistical methods to determine the significance of the observed trends.V. ConclusionsBased on the results obtained, the following conclusions can be drawn:1. The rate of the chemical reaction increased with an increase in temperature, as expected from the Arrhenius equation.2. The rate of the chemical reaction increased with an increase in pressure, suggesting that the reaction is pressure-sensitive.3. The relationship between temperature and pressure in terms of their influence on the rate of the chemical reaction can be described using a combined kinetic model.4. The experimental results were consistent with the theoretical predictions based on established kinetic models.5. The optimal conditions for the chemical reaction were identified, which can be used to optimize the reaction process in industrial applications.In conclusion, the objectives of the experiment were successfully achieved. The experiment provided valuable insights into the effects of temperature and pressure on the rate of a chemical reaction, which can be applied to optimize reaction processes and improve the efficiency of industrial applications. Further research can be conducted toinvestigate the influence of other factors, such as catalysts and reactant concentrations, on the reaction rate.References:[1] Smith, J., & Johnson, A. (2010). The effects of temperature and pressure on chemical reactions. Journal of Chemical Engineering, 56(3), 45-58.[2] Brown, T., & White, M. (2015). Kinetics and mechanism of chemical reactions. Chemical Engineering Progress, 101(2), 89-102.[3] Smith, J., & Brown, T. (2018). Optimization of reaction processes using kinetic models. Chemical Engineering Research and Design, 123(2), 385-395.。
