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A reaction range for hydration

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Areactionrangeforhydrationofcalciumsulfoaluminatewithcalciumsulfateandcalciumhydroxide:theoryandexperimentalvalidationJunChangProfessor,SchoolofCivilEngineering,DalianUniversityofTechnology,Dalian,China(correspondingauthor:mlchang@dlut.edu.cn)XinYuGraduateStudent,SchoolofCivilEngineering,DalianUniversityofTechnology,Dalian,ChinaXiaopengShangPhDStudent,SchoolofCivilEngineering,DalianUniversityofTechnology,Dalian,ChinaJiuyeZhaoPhDStudent,SchoolofCivilEngineering,DalianUniversityofTechnology,Dalian,ChinaYangyangZhangGraduateStudent,SchoolofCivilEngineering,DalianUniversityofTechnology,Dalian,China

Tobetterinvestigateandunderstandthehydrationofcalciumsulfoaluminate(CSA)cement,atheoryreactionrangeforthehydrationofCSAwithcalciumsulfateandcalciumhydroxidewasestablishedbytheoreticalcalculationwithahypotheticalhydrationreactionsystem.Withdifferentamountsofcalciumsulfateandcalciumhydroxideinthereactionsystems,theirhydrationprocesses,hydrationproductsandstoichiometricwater/solidratiosshowedregularchanges.Apreliminaryexperimentalvalidationwasmadebyanalysingthehydrationproducts(curingtime28dandwater/solidratioof10)ofseveralcompositionpointsinthetheoryreactionrangebymeansofx-raydiffractionandthermogravimetricanalysis.Theprocessforcalculationofthetheoryreactionrangeandsomeoftheexperimentalvalidationresultsarepresentedinthispaper.NotationaamountofCaSO4.2H2O(CŠH2)inthehypotheticalreactionsystembamountofCa(OH)2(CH)inthehypotheticalreactionsystemtmolarratioofAFt(ettringite)toMs12(monosulfoaluminate)wamountof4CaO.3Al2O3.SO3(C4A3Š)participatinginReactionIVxamountofC4A3ŠparticipatinginReactionIyamountofC4A3ŠparticipatinginReactionIIzamountofC4A3ŠparticipatinginReactionIIIIntroductionCalciumsulfoaluminate(CSA)cementhasbeenproduced,usedandstandardisedinChinaformorethan30yearssinceitwasdevelopedbytheChinaBuildingMaterialsAcademyinthe1970s(CRD,1978;Suetal.,1992;WangandGlasser,1996;Wangetal.,1999).ComparedwiththemanufactureofPortlandcement,theproductionofCSAcementcanreducecarbondioxideemissionsbyabout40%(Desboisetal.,2010;Gartner,2004;Juengeretal.,2011).ThesinteringtemperatureusedtoproduceCSAcementclinkerisabout200°ClowerthanthatusedforPortlandcementclinker(Desboisetal.,2010;Juengeretal.,2011)and,inaddition,iseasiertogrind(Juengeretal.,2011).ConcretebasedonCSAcementexhibitsahighresistancetofreeze–thawdamageandoffersfavourabledurabilityinarangeofaggressiveenvironments(Juengeretal.,2011;Tangetal.,2015).AlthoughitisnotwidelyusedinEuropeortheUSA,productsmadeusingCSAcementcanbeappliedinmanyareasandthuspresentapromisingmarket.Calciumsulfoaluminate(4CaO.3Al2O3.SO3orC4A3Š)wasfirstintroducedasacementitiousphasebyAlexanderKleininthe1960s(Klein,1963).Asthemain(30–70%)constituentofCSAcement(Juengeretal.,2011;Wangetal.,1999),C4A3Šplaysakeyroleincementperformance(WangandGlasser,1996),soitshydrationbehaviourisimportant.Furthermore,thepropertiesofCSAcement–includingsettingtime,strengthdevelopment,kineticsofhydrationandproductdevelopment–areinfluencedbytheadditionofcalciumsulfateorcalciumhydroxide(KaprálikandHanic,1989;PalouandMarling,1996;SongandYoung,2002;WangandGlasser,

1996;1AdvancesinCementResearchAreactionrangeforhydrationofcalciumsulfoaluminatewithcalciumsulfateandcalciumhydroxide:theoryandexperimentalvalidationChang,Yu,Shang,ZhaoandZhangAdvancesinCementResearchhttp://dx.doi.org/10.1680/jadcr.16.00045Paper1600045Received10/04/2016;revised29/07/2016;accepted31/07/2016Keywords:gypsum(hemihydrate,anhydrite)/hydration/limeICEPublishing:Allrightsreserved

Downloaded by [ Dalian University of Technology] on [07/09/16]. Copyright © ICE Publishing, all rights reserved.Wangetal.,1999;WinnefeldandBarlag,2010;ZhangandGlasser,2002;Zhangetal.,1999).Thereactivityofaddedcalciumsulfateisalsoanimportantfactor(GlasserandZhang,2001;Majlingetal.,1985;WinnefeldandBarlag,2009,2010;WinnefeldandLothenbach,2010;ZhangandGlasser,2002).Previousstudieshaveconcludedthatettringiteformedunderahighlimeconcentrationcausedexpansion,whereasettringiteformationinlime-deficientmixturesdidnotresultinexpansion(Kasselourietal.,1995;Mehta,1973;Micheletal.,2011;WangandGlasser,1996;WinnefeldandBarlag,2009).PreviousresearchonthehydrationofC4A3Šhasmainlybeenfocusedonseveralspecifichydrationreactions.C4A3Šreactswithwateralonetoformmonosulfoaluminate(C4AŠH12orMs12)andaluminiumhydroxide(AH3)accordingtoReactionIatlowwater/solidratios(Bizzozeroetal.,2014;DidamonyandSokkari,2012;Hanicetal.,1989;KaprálikandHanic,1989;Martinetal.,2005;Sánchez-Herreroetal.,2013;SongandYoung,2002;Torréns-Martínetal.,2013).Inanenvironmentwithhigherwatercontent,ettringite(C6AŠ3H32orAFt)isalsodetectable(Cuestaetal.,2014;DidamonyandSokkari,2012;Martinetal.,2005;Sánchez-Herreroetal.,2013;Torréns-Martínetal.,2013;WinnefeldandBarlag,2010).ThehydrationofC4A3Šwithcalciumsulfate(CŠ)leadstothefor-mationofAFtandAH3,followingReactionII(Beretkaetal.,1996;Bizzozeroetal.,2014;García-Matéetal.,2013;Hanicetal.,1989;KaprálikandHanic,1989;Kasselourietal.,1995;Tangetal.,2015;WinnefeldandBarlag,2010).WithacertainamountofCŠandcalciumhydroxide(CH)involvedinthesystem,therearetwospecifichydrationreactions(Hanicetal.,1989;Hargisetal.,2013;HavlicaandSahu,1992;KaprálikandHanic,1989;Mehta,1973;OdlerandColán-Subauste,1999;OgawaandRoy,1981)andthefinalhydrationproductsaremonosulfoaluminateandettringite,respectively,accordingtoReactionsIIIandIV.I:C4A3ˇSþ18H!C4AˇSH12þ2AH3

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十六烷基三甲基溴化铵促进CO2水合物生成实验

十六烷基三甲基溴化铵促进CO2水合物生成实验

Feb．2013现代化工第33卷第2期ModernChemicalIndustry2013年2月

十六烷基三甲基溴化铵促进

CO2水合物生成的实验研究

周诗岽1，2，王树立2，张国忠1

（1．中国石油大学（华东）储运与建筑工程学院，山东青岛266580；2．常州大学油气储运技术省重点实验室，江苏常州213016）

摘要：针对CO2水合物自然生成速度慢这一技术难题，利用实验室自制的水合物实验系统，开展了十六烷基三甲基溴化铵（CTAB）体系下CO2水合物生成促进实验研究。考察了CTAB质量分数为200、300、500、700、900mg/kg下对水合反应体系表面张力及CO2水合物生成特性影响规律，分析了CTAB对CO2水合物生成促进作用机理。实验结果表明，5种浓度下CTAB添加剂均能够有效降低CO2水合物相平衡点，温度越高，生成压力降低幅度越大，在最优用量为300mg/kg下降幅可达27.7%。水合反应体系的压力越低，CTAB促进CO2水合物生成的诱导时间降低越大，促进效果越明显。该研究对于提高水合物生成速率具有一定的意义。关键词：CTAB；水合物；CO2中图分类号：TQ517文献标志码：A文章编号：0253－4320（2013）02－0060－04AnalysisonphenomenonandmechanismofCO2hydrateformationwithCTABadditiveZHOUShi-dong1，2，WANGShu-li2，ZHANGGuo-zhong1（1．CollegeofPipeline＆CivilEngineering，ChinaUniversityofPetroleum，Qingdao266580，China；2．JiangsuKeyLaboratoryofOilandGasStorageandTransportationTechnology，ChangzhouUniversity，Changzhou213016，China）

呋喃二甲酸生产工艺流程

呋喃二甲酸生产工艺流程

呋喃二甲酸生产工艺流程

英文回答：

Furan-2,5-dicarboxylic Acid Production Process.

Furan-2,5-dicarboxylic acid (FDCA) is a bio-based

platform chemical that is gaining interest as a sustainable

alternative to petrochemical-based plastics. FDCA can be

produced from a variety of renewable feedstocks, including

biomass, sugars, and bio-based furanics.

Process Flow.

The most common process for producing FDCA is a two-step process that involves the oxidation of furfural to

maleic anhydride, followed by the hydration of maleic

anhydride to FDCA.

Step 1: Oxidation of Furfural to Maleic Anhydride.

Furfural is oxidized to maleic anhydride in a catalytic

reactor. The most commonly used catalysts for this reaction

are vanadium-based catalysts. The reaction is carried out

at elevated temperatures (300-400°C) and pressures (10-20

专业英语-8

专业英语-8

Preparation of Alcohols: A Review

Alcohols occupy a central position in organic chemistry. They can be prepared from

many other kinds of compounds (alkenes, alkyl halides, ketones, esters, and

aldehydes, among others), and they can be transformed into an equally wide

assortment of compounds.

Let’s review briefly some of the methods of alcohol preparation we’ve already

seen:

 Alcohols can be prepared by hydration of alkenes. Because the direct hydration of

alkenes with aqueous acid is generally a poor reaction in the laboratory (low

product yields, harsh reaction conditions), two indirect methods are commonly

used. Hydroboration/oxidation yields the product of syn, non-Markovnikov

hydration, whereas oxymercuration/reduction yields the product of Markovnikov

hydration. Both reactions are generally applicable to most alkenes.

乙醇的制备方法及工艺流程

乙醇的制备方法及工艺流程

乙醇的制备方法及工艺流程

英文回答：

To prepare ethanol, there are several methods and

processes available. One common method is the fermentation

of sugars by yeast. This process involves the conversion of

sugars, such as glucose or sucrose, into ethanol and carbon

dioxide through the action of enzymes present in yeast. The

fermentation process can take place in a controlled

environment, such as a bioreactor, where the yeast is

provided with a suitable medium containing sugars, water,

and nutrients. The yeast consumes the sugars and produces

ethanol as a byproduct.

Another method for ethanol production is through the

hydration of ethylene. Ethylene, which is derived from

petroleum or natural gas, is reacted with water in the

presence of a catalyst, such as phosphoric acid or sulfuric

acid, to produce ethanol. This process is commonly known as