常压下甲醇和环氧乙烷的反应研究

提出了在CMG固体酸催化剂存在下甲醇与环氧己烷的乙氧基化反应效果,采用釜式反应器,n(甲醇)∶n(环氧己烷)=10∶1～4∶1,催化剂的用量为甲醇质量的1%～2%,反应温度65～75 ℃、操作压力为常压,环氧乙烷的转化率接近100%,选择性高于93%,并成功地完成了工业放大.     

乙二醇双子琥珀酸2-乙基丁基酯磺酸钠的合成及性能

采用碳基固体酸作酯化反应催化剂于常压下反应的方法合成了乙二醇双子琥珀酸2-乙基丁基酯磺酸钠,酯化反应无需有机溶剂,磺化反应不外加相转移催化剂。最佳工艺条件为:单酯化反应,n(乙二醇)∶n(顺酐)=1.00∶2.10,催化剂碳基固体酸用量为顺酐质量的2%,100℃反应4.7 h,酯化率99.21%(质量分数);双酯化反应,n(2-乙基-1-丁醇)∶n(顺酐)=1.30∶1.00,于210℃反应1 h,酯化率95.17%(质量分数);磺化反应,n(亚硫酸氢钠)∶n(顺酐)=1.05∶1.00,于120℃反应1 h,磺化率100.65%(质量分数)。对产物结构进行了IR和1HNMR光谱表征,对产物性能进行了测定:CMC为2.99×10-3mol/L,γCMC为27.96 mN/m,乳化力4.35 min,渗透力为11.6 s,耐硬水力为13.3 min。     

新型固体酸催化7-羟基-4-甲基香豆素的无溶剂合成

以新型固体酸为催化剂,乙酰乙酸乙酯和间苯二酚为原料,通过Pechmann反应在无溶剂条件下合成了7-羟基-4-甲基香豆素。探讨了以新型固体酸为催化剂时反应温度、催化剂用量、反应时间、原料配比诸因素对产品收率的影响。实验表明,新型固体酸是合成7-羟基-4-甲基香豆素的良好催化剂,在反应温度为120℃,反应时间70min,n(间苯二酚)∶n(乙酰乙酸乙酯)=1∶1.2,催化剂的用量0.9g(间苯二酚的物质的量0.04mol)时,产品的收率为66.5%。     

甘蔗渣炭基固体酸的制备及催化合成乙酸甲酯研究

以甘蔗渣为原料通过炭化-磺化的方法制备了甘蔗渣炭基固体酸,探讨了制备工艺条件对固体酸催化剂性能的影响。以正交实验对酯化反应温度、固体酸加入量、酸醇物质的量比、反应时间等影响合成乙酸甲酯的因素进行了优化,并考察了催化剂的稳定性。实验结果表明,制备固体酸催化剂较合理的条件为:炭化温度300℃,炭化时间2.0 h,磺化温度90℃,磺化时间8.0 h。正交实验结果表明,在催化剂用量为乙酸质量的3%、酯化反应时间为2.5 h、n(乙酸)∶n(甲醇)=1∶3、酯化反应温度为65℃的条件下,乙酸转化率为86.5%,且催化剂的稳定性良好,可循环使用7次。该研究结果为乙酸甲酯的合成提供了一种新型催化剂。     

利用固体催化剂制备丙酮缩甘油的工艺研究

以固体酸作为催化剂,以甘油和丙酮为原料合成丙酮缩甘油,考察了反应温度、反应时间、反应物配比、催化剂用量对反应的影响。实验结果表明,甲苯为带水剂,催化剂用量为甘油质量的6%,原料n(甘油)∶n(丙酮)为1∶3,反应时间为6 h,反应的温度为80℃,丙酮缩甘油的产率可达80%。本文采用固体酸作为催化剂,产品易分离且无需除酸,后处理简单。     

碳基固体酸催化合成月桂醇聚氧乙烯醚(7)异辛基磺基琥珀酸混合双酯钠

采用碳基固体酸为酯化反应催化剂,合成了月桂醇聚氧乙烯醚(7)异辛基磺基琥珀酸混合双酯钠,对各步反应进行考察,得到最佳工艺条件为:单酯化反应:n(顺酐)∶n(聚醚7)=1.10∶1.00,ω(碳基固体酸)=1%(以顺酐质量计),反应温度130℃,反应时间2.5 h,在此条件下得到产率为98.16%的单酯化产物;双酯化反应:n(顺酐)∶n(异辛醇)=1.00∶2.00,反应温度200℃,反应时间5.0 h,在此条件下得到产率为93.94%的双酯化产物。测定了产物的表面性能和应用性能,并与对甲苯磺酸作催化剂进行了比较。结果表明:碳基固体酸做催化剂时异辛醇用量少了一半;产物性能一致。     

尼龙酸二丁酯的合成

尼龙酸在固体酸催化下,与丁醇直接酯化、减压蒸馏制得合格的尼龙酸二丁酯。研究催化剂用量、原料水分和配比、反应温度和时间及蒸馏压力等因素对其制备产品的影响。其最佳工艺条件为:①酯化反应:催化剂用量为反应物总质量的1.0%～1.5%,n(丁醇)∶n(尼龙酸)=2.2∶1.0,在搅拌下,反应温度控制在145～155℃,反应时间9～10h;②减压蒸馏:蒸馏压力≤5.0kPa。     

固体超强酸SO2-4/TiO2/La3+催化合成二甲基丙烯酸丁二醇酯

以自制稀土改性固体超强酸SO2-4/TiO2/La3+为催化剂,高效合成了二甲基丙烯酸丁二醇酯.比较了不同催化剂的催化活性,并考察了固体酸的制备条件及酯化反应条件对催化活性的影响,得到最佳合成条件为:SO2-4/TiO2/La3+于500 ℃下活化3 h,n(酸)∶n(醇)=2.8∶1,阻聚剂、催化剂质量分数分别为1.0%和1.2%,反应温度维持在120 ℃左右反应2 h左右,酯化率可达92.0%.     

硫酸铵改性粉煤灰催化合成环己酮乙二醇缩酮

以粉煤灰（FA）为原料制备了一种新型的固体酸催化剂,用X射线衍射、热分析和红外光谱等手段表征了催化剂的物化性能。研究了催化剂在环己酮与乙二醇的缩合反应中的催化性能,系统考察了带水剂种类、带水剂用量、酮醇量比、催化剂用量、反应时间等因素对缩酮产率的影响。通过正交实验得出了最佳反应条件：n(环己酮)∶n(乙二醇)=1∶1.4、催化剂用量为环己酮质量的2%、带水剂环己烷用量10.0 mL、反应时间2 h,缩酮产率可达99.6%。该催化剂活性较高,可重复使用。     

复合固体超强酸SO42-/ZrO2-TiO2催化合成己二酸二(2-乙基)己酯

以复合固体超强酸SO42-/ZrO2-TiO2为催化剂合成了己二酸二(2-乙基)己酯,考察了催化剂用量、酸醇投料比和反应温度对反应的影响.结果表明,最佳合成工艺条件为:催化剂用量为1.5%(占总投料量质量分数)、酸醇投料比为n(己二酸)∶n(2-EH) =1∶2.5、反应温度195～ 200℃、反应时间2.5 h,此时产品收率达97.6%.催化剂可重复使用6次,再生容易.     

磷钨杂多酸掺杂聚苯胺催化合成环己酮乙二醇缩酮

采用浸渍法制备的磷钨杂多酸掺杂聚苯胺H3PW12O40/PAn作催化剂,通过环己酮和乙二醇为原料合成环己酮乙二醇缩酮,探讨了磷钨酸掺杂聚苯胺催化剂对缩酮反应的催化活性,系统地研究了原料量比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明,在n环己酮∶n乙二醇=1∶1.5(物质的量比),催化剂用量为反应物料总质量的0.25%,环己烷为带水剂,反应时间1.0 h的优化条件下,环己酮乙二醇缩酮的收率可达80.4%。     

Toward a CO2-free ethylene oxide process: Homogeneous ethylene oxide in gas-expanded liquids

Among industrial chemical processes, ethylene oxide manufacture emits the largest amount of CO₂ (∼2-3 million tons/yr), as byproduct from the burning of both the ethylene (feed) and ethylene oxide. Further, the conventional silver-based catalytic process presents safety challenges due to the formation of explosive ethylene oxide/O₂ mixtures in the gas phase. By judicious choice of the catalyst (methyltrioxorhenium), oxidant (H₂O₂) and reaction medium (methanol/water), a homogeneous liquid phase catalytic system has been demonstrated that eliminates CO₂ formation while producing ethylene oxide at >90% selectivity at near-ambient temperatures. Given its high volatility, the ethylene oxide is easily recovered from the reaction phase by distillation. The vicinity of the gaseous ethylene feed to its critical temperature (9 °C) is exploited to significantly increase its solubility in the liquid reaction phase by facile compression beyond the critical pressure of ethylene (∼50 bar). Since H₂O₂ is stable at typical reaction temperatures (40 °C or less), potentially explosive ethylene oxide/O₂ mixtures are avoided in the gas phase. In addition to the potential of arresting the carbon footprint of a large-scale industrial process, the demonstrated process concept shows how gas-expanded liquids can be generally exploited in homogeneous catalysis to enhance productivity.     

Dynamic mathematical modeling of a novel dual-type industrial ethylene oxide (EO) reactor

In this paper, the dynamic behavior of a novel dual-type industrial ethylene oxide reactor has been proposed with taking catalyst deactivation into account. The configuration of two catalyst beds instead of one single catalyst bed is developed for conversion of ethylene to ethylene oxide. In the first reactor which is an industrial fixed-bed water-cooled reactor, the feed gas is partly converted to ethylene oxide. This reactor functions at very high yield and at a higher than normal operating temperature. In the second converter, the reaction heat is used to preheat the feed gas to the first reactor and a milder temperature profile is observed. The potential possibilities of a two-stage catalyst bed system are analyzed using a 1D heterogeneous dynamic model to obtain necessary comparative estimates. A differential evolution (DE) algorithm is applied as an effective and robust method to optimize the reactors length ratio. The results obtained from the simulation demonstrate that there is a desirable catalyst temperature profile along the dual-type reactor (DR) compared with the conventional single-type reactor (SR). In this way, the catalysts are exposed to less extreme temperatures and thus, diminishing the catalyst deactivation via sintering. Results from this study provided beneficial information about the effects of reactors configuration on catalyst lifetime and ethylene oxide production rate simultaneously.     

环氧乙烷催化水合制乙二醇催化剂研究进展

介绍了从催化水合法、碳酸乙烯酯法、乙二醇与碳酸二甲酯联产法制备乙二醇的均相催化剂和非均相催化剂,分析了催化剂的应用状况,提出了采用新技术合成乙二醇的建议。     

加压一步法合成碳酸乙烯酯

对ＮＢ－１催化剂存在下环氧乙烷和二氧化碳合成碳酸乙烯酯的反应进行了实验室研究，确定了加压一步合成碳酸乙烯酯的最佳工艺条件。在此条件下，碳酸乙烯酯产品纯度在９９．０％以上，总收率大于９８．０％。该工艺已在河北省唐山朝阳化工总厂实现了１５００ｔ／ａ碳酸乙烯酯工业化生产，产品填补了国内空白。     

IR study of the secondary reaction of ethylene oxide over silver catalyst supported on mesoporous material

The secondary reaction of ethylene oxide over silver catalyst supported on MCM-41 mesoporous material was investigated by thein-situ IR method. MCM-41 mesoporous material with a large content of hydroxyl group was very active in catalyzing the isomerization of ethylene oxide to acetaldehyde. The reduction of hydroxyl group by silane treatment or silver loading suppressed the isomerization of ethylene oxide. The selectivity for ethylene oxide in the partial oxidation of ethylene is enhanced by silane modification, revealing the acceleration of the consumption of ethylene oxide on the hydroxyl group.     

固体酸SO_3/γ-Al_2O_3催化合成环己酮乙二醇缩酮工艺研究

以环己酮和乙二醇为原料,固体酸为催化剂,环己烷为带水剂,通过醇醛亲核加成反应合成了环己酮乙二醇缩酮。考察了催化剂用量、醛醇摩尔比、反应时间等因素对产品收率的影响。结果表明：SO3/γ-Al2O3固体酸具有良好的催化活性,较优工艺条件为：环己酮20.8 mL（0.20 mol）,n（环己酮）/n（乙二醇）=1︰1.2,催化剂0.5 g,环己烷10 mL,回流时间1.0 h,产物收率达96%以上。     

乙烯氧化制环氧乙烷催化剂的技术进展

银催化剂是乙烯和氧气直接氧化反应生产环氧乙烷的核心,其性能尤其是选择性在很大程度上影响着生产的经济效益。介绍了国内外银催化剂的技术进展和工业应用情况,同时,对我国银催化剂的研发重点提出了一些建议。     

催化环氧乙烷氢甲酯化的催化体系研究

以Co2(CO)8为催化剂,甲醇为溶剂,在一定CO压力下,催化环氧乙烷氢甲酯化合成3-羟基丙酸甲酯。考察了不同配体、催化剂/配体的摩尔比、温度、CO压力、甲醇用量对环氧乙烷氢甲酯化反应的影响。得到较佳合成工艺条件为:咪唑为配体、n(催化剂)∶n(配体)=1∶1.5、反应温度75℃、反应压力6.0 MPa、V(甲醇)∶V(环氧乙烷)=5∶1。在该优化条件下,环氧乙烷转化率为92.24%,3-羟基丙酸甲酯收率达84.35%。     

Investigation of three types of catalysts for the hydration of ethylene oxide (EO) to monoethylene glycol (MEG)

Amine compounds, bi-functional compounds (EDTA, ethylene diamine tetra acetic acid type), and Salen compounds were investigated for catalytic hydration of ethylene oxide (EO) to monoethylene glycol (MEG). Many of the catalysts studied are selective for the formation of MEG compared with thermal hydration without any catalyst present. The results of the catalytic hydration with three types of catalysts were rationalized using acid and base catalyzed reaction mechanisms.