国内丁酸丁酯的催化合成研究进展

综述了采用磺酸、无机盐、固体超强酸、杂多酸、酶、相转移等催化体系催化合成食用香料丁酸丁酯的方法;阐述了在各催化剂作用下的反应条件、催化剂的性质及合成工艺的特点;列举了各催化剂在产率、反应时间、后处理工艺、是否可重复使用、带水剂及是否易于保存和使用等方面所具有的优势;指出不加带水剂,高效催化剂的固载化及开发环保型、高效型、经济型的催化合成体系是今后的研究方向。     

环境友好催化剂催化合成己二酸二乙酯

评述了强酸性阳离子交换树脂、十二水合硫酸铁铵、硫酸铜、一水硫酸氢钠、固体超强酸、杂多酸和分子筛催化制备己二酸二乙酯的方法。阐述了在上述催化剂作用下的反应条件、催化剂的性质以及合成工艺的特点,列举了各种催化剂在反应时间、带水剂、产率以及是否可重复使用等方面所具有的优势,指出上述讨论的几种固体催化剂都是合成己二酸二乙酯的优良催化剂。     

硫酸氢钠催化乙酸异丙酯合成工艺的研究

本文以冰乙酸和异丙醇为原料合成乙酸异丙酯。主要考察催化剂种类、催化剂用量、醇酸物质的量比、反应时间、带水剂种类、带水剂用量对乙酸异丙酯产率的影响,确定合成乙酸异丙酯的最佳工艺条件。实验结果表明,相对于其它催化剂,硫酸氢钠催化高效且环保。乙酸异丙酯合成的最佳合成工艺条件为:反应时间为1.5 h,催化剂用量为1.5 g,醇酸物质的量比为1∶1.5,带水剂用量10 mL,此时乙酸异丙酯产率可达62.9%。     

硫酸氢钠催化合成富马酸二异辛酯

以富马酸和异辛醇为原料,NaHSO4做催化剂,甲苯做带水剂,合成了富马酸二异辛酯.用正交实验设计方法考察了醇酸比、催化剂用量、带水剂用量、反应时间等因素对反应的影响,确定了NaHSO4催化法合成富马酸二异辛酯的最佳工艺条件为:醇酸比为5:1,催化剂用量为酸质量的2％,带水剂用量为醇用量的1/2,反应时间为4h,产率达98％.     

癸二酸二正己酯的催化合成

以癸二酸和正己醇为原料、SO42-/ZrO2为催化剂、甲苯为带水剂合成了癸二酸二正己酯。考察了醇酸摩尔比、催化剂用量、反应温度、反应时间、带水剂用量对癸二酸酯化率的影响。确定了最佳工艺条件:醇酸摩尔比为2.9,催化剂用量为4.8%,反应温度为195℃,反应时间为1.5h,带水剂用量为75%。在最佳工艺条件下,癸二酸的酯化率可达98%以上。     

硫酸氢钠催化合成丙二醇甲醚醋酸酯的研究

以醋酸和丙二醇甲醚为原料,硫酸氢钠为催化剂,环己烷为带水剂合成丙二醇甲醚醋酸酯,考察了原料醇酸配比、催化剂用量、带水剂用量、反应时间等因素对转化率的影响。通过实验结果分析对比,得到较佳实验反应条件：在原料酸醇配比为1.5,催化剂用量为原料总质量的3%,带水剂用量为原料总质量的15%,反应时间为3 h的工艺条件下,丙二醇甲醚的转化率达到96%以上。     

维生素C催化合成糠醛1,2–丙二醇缩醛

以维生素C为催化剂,糠醛和1,2–丙二醇为原料,催化合成了糠醛1,2–丙二醇缩醛。详细探索了醛醇摩尔比、催化剂用量、带水剂用量、带水剂种类、反应时间等因素对收率的影响。得出了维生素C催化合成糠醛1,2–丙二醇缩醛最佳工艺条件:以糠醛0.2 mol为标准,醛醇摩尔比1∶1.3,带水剂用量10 m L,维生素C用量0.8 g,反应时间90 min,反应温度为回流温度,在此最佳条件下,得出缩醛的收率为75.86%。该工艺具有操作简单,反应条件温和,产品易于分离等优点。     

活性炭负载磷钨酸催化合成环己酮乙二醇缩酮

以活性炭负载磷钨酸为催化剂,环己酮和乙二醇为原料,催化合成了环己酮乙二醇缩酮。详细探索了醛醇摩尔比、催化剂用量、带水剂用量、反应时间等因素对收率的影响。得到了活性炭负载磷钨酸催化合成环己酮乙二醇缩酮优化工艺条件：以环己酮0.1mol为标准,酮醇物质的量比1∶1.6,带水剂环己烷用量12mL,催化剂用量0.6g,反应时间30min,反应温度为回流温度,在此优化条件下,缩醛的收率为87.7%。结果表明,活性炭负载磷钨酸催化剂是合成环己酮乙二醇缩酮的良好催化剂,可重复使用。该工艺具有操作简单,反应条件温和,产品易于分离等优点。     

Keggin型P-Mo-V杂多酸催化合成苯甲酸正丁酯

以苯甲酸和正丁醇为原料,甲苯为带水剂,用自制的Keggin型钼钒磷杂多酸为催化剂,合成了苯甲酸正丁酯。探讨了催化剂用量、原料配比、带水剂用量和反应时间对产品收率的影响,并用多种手段对产品做了检测分析。结果表明,合成该酯的最佳工艺条件为:n(正丁醇)/n(苯甲酸)=3,催化剂用量为反应物料总质量的12%,甲苯做带水剂,反应温度控制在110～115℃,反应时间2h。在此条件下,酯收率可达80 49%。     

无毒增塑剂柠檬酸三乙酯的合成研究

简要介绍了柠檬酸和乙醇在催化剂条件下,以乙醇为带水剂,进行高纯度柠檬酸三乙酯的合成,考察了催化剂的种类和用量以及反应温度和时间等因素对柠檬酸三乙酯合成过程影响。     

Synthesis of alkyl polyglycosides: Effect of catalyst-type on reaction rate and product composition

The technically important synthesis of alkyl polyglycosides from fatty alcohols and D -glucose was investigated on a laboratory scale. A new simple method to quantify the rate of this complex reaction by measuring the formation of water is described. The influence of the concentration and the kind of the sulfonic acids used as catalysts on the reaction rate and the composition of the products was determined and correlated to the Taft-constants σ*. It was shown that the reaction rate observed for the different catalysts is mainly an effect of their acidity. Thus, neighbouring group effects of catalysts such as 10-camphorsulfonic acid (bulky substituent) or sulfosuccinic acid (polar substituent) seem not to exist. Due to the heterogeneous character of the reaction the rate-concentration plots gave saturation curves. Finally, the influence of the particle size of the crystalline glucose on the reaction rate and the composition of the product was investigated. The use of the finest-grained glucose gave the best product with only a small amount of polymers and a high reaction rate.     

实验条件对活性炭基固体酸催化剂制备的影响

以煤基商品活性炭为载体,通过苯磺酸重氮盐还原反应制备活性炭基固体酸催化剂。系统考察了重氮盐制备方法,无水乙醇、蒸馏水、次磷酸的用量等实验条件对炭基固体酸催化剂磺酸密度以及催化活性的影响。研究得到的最优实验条件是,苯磺酸重氮盐无需抽滤处理,重氮盐制备反应时间为45 min、无水乙醇用量为50 mL、不加蒸馏水、次磷酸用量300 mL,该条件下得到的炭催化剂磺酸密度达到1.46 mmol/g,超过目前催化剂磺酸密度的2倍,其对乙酸酯化反应的催化性能比未优化时提高了38%。     

草酸二丁酯的催化合成

以草酸和正丁醇为原料，分别采用不同催化剂——对甲苯磺酸和强酸性阳离子交换树脂合成草酸二丁酯，用正交实验法研究了两种催化剂对该反应的催化性能；确定了各自的最佳合成条件。以对甲苯磺酸为催化剂，在醇酸比为4：1，催化剂用量15％，回流分水1h，以苯为带水剂的反应条件下，酯收率达83．6％；以强酸性阳离子交换树脂为催化剂，在醇酸比3：1，催化剂用量10％，回流分水1．5h，以甲苯为带水剂的反应条件下，酯收率达89．5％，且催化剂可重复使用。     

Mesoporous silicon sulfonic acid as a highly efficient and stable catalyst for the selective hydroamination of cyclohexene with cyclohexylamine to dicyclohexylamine in the vapor phase

In this work, a new mesoporous silicon sulfonic acid catalyst derived from silicic acid has been successfully prepared by the chemical bonding method. The physicochemical properties of mesoporous silicon sulfonic acid catalysts have been systematically characterized using various techniques. The results demonstrate that sulfonic acid groups have been grafted on silicic acid by forming a new chemical bond (Si–O–S). The mesoporous silicon sulfonic acid exhibits excellent catalytic performance and stability in the vapor phase hydroamination reaction of cyclohexene with cyclohexylamine. Cyclohexene conversion of 61% and 97% selectivity to dicyclohexylamine was maintained after running the reaction for over 350 h at 280 °C. The developed mesoporous silicon sulfonic acid catalyst shows advantages of low cost, superior acid site accessibility, and long term reactivity stability. Moreover, a possible catalytic hydroamination reaction mechanism over silicon sulfonic acid was suggested. It has been demonstrated that the sulfonic acid groups of the catalyst play an important role in the hydroamination. The present work provides a simple, efficient, and environmentally friendly method for the hydroamination of cyclohexene to valuable dicyclohexylamine, which also shows important industrial application prospects.     

磺酸功能化咪唑类离子液体催化丁二酸与丁二醇预聚酯化的过程研究

采用咪唑、1,3-丙磺酸内酯、1,2-二溴乙烷、1,4-二溴丁烷和聚乙二醇-200等为原材料合成了四种功能性磺酸类咪唑离子液体,考察了这四种离子液体催化剂酯化合成丁二酸丁二醇酯的性能,研究了催化剂用量、醇酸摩尔比、反应时间等因素对酯化反应的影响,并与钛酸正丁酯及钛酸异丙酯催化剂进行对比,得出其较佳工艺条件为:使用双-(3-丙烷磺酸-1-亚丁基咪唑)磺酸功能化离子液体为催化剂,用量为丁二酸摩尔质量的0.40%,醇酸比为1.3:1,反应温度160℃,反应时间为2 h,酯化率最高达到94.2%.     

乙酸环己酯的催化合成研究进展

综述了磺酸、固体超强酸、无机盐、杂多酸催化体系催化合成乙酸环己酯的方法;阐述了在各催化剂作用下的反应条件,催化剂的性质及合成工艺的特点;列举了各催化剂在产率、反应时间、后处理工艺、是否可重复使用等方面所具有的优势;指出高效催化剂的固载化及开发环保型、高效型、经济型的催化剂合成体系是今后的研究方向,     

Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated. The synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscope-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area, thermogravimetric analysis and n-butylamine acidity. The shape of catalysts particles plays an important role in its activity. The sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel production. The catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid, oleic acid with methanol. The effect of various reaction parameters such as catalyst concentration, acid/alcohol molar ratio, catalyst amount, reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum conversion. It was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica catalysts. Additionally, the catalyst was regenerated and reused up to three cycles without any significant loss in activity. The present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.     

Hydrothermal degradation of model sulfonic acid compounds: Probing the relative sulfur–carbon bond strength in water

Development of heterogeneous catalysts for the biorenewable industry requires hydrothermal degradation resistance. However, the relationship between hydrothermal stability and the immediate electronic hybridization of the carbon atoms adjacent to the sulfonic acid active group is not fully known. We systematically tested model compounds containing sulfonic acid groups linked to aromatic, alkane, or cycloalkane carbon atoms. We subjected them to hydrothermal conditions. The compounds' structural integrity was monitored with solution NMR. The aromatic-sulfonic acid compounds degraded readily, while the hydrolysis of the alkyl sulfonic acid linkages was negligible. Therefore, hydrothermally stable sulfonic-acid catalysts need sulfonic acid attached via alkyl linkers.