酯化法合成丁二酸二乙酯

以丁二酸和无水乙醇为原料,硫酸氢钠为催化剂合成丁二酸二乙酯,考察了影响收率的各种因素,确定了最佳反应条件为:丁二酸用量0.1mol时,无水乙醇与戊二酸的物质的量比为6.0,3.0g催化剂,25mL环己烷作带水剂,反应时间2.0h,收率达85.09%,结果表明,硫酸氢钠是合成丁二酸二乙酯的优良催化剂。     

丁二酸单乙酯酰氯的合成

以丁二酸酐 ,无水乙醇 ,氯化亚砜为原料 ,经过酯化和酰化两步反应合成丁二酸单乙酯酰氯 ,在原料物质量比为丁二酸酐∶乙醇∶氯化亚砜 =1∶1.2∶1.2 ,酯化温度 80℃ ,反应时间 1h ,酰化温度 95℃ ,反应时间 3h的条件下 ,产品收率达 82 % (以丁二酸酐计 )     

对甲苯磺酸催化合成丁二酸二甲酯的研究

对甲苯磺酸作为丁二酸和甲醇的酯化催化剂,性能优于硫酸。本文探讨并找到了其较好的反应条件,酯化率达95．0％。     

气相色谱法测定丁二酸酯化液中有机组分的含量

针对丁二酸酯化液的特点,选择强极性毛细管柱作为分析柱,优化得到了分析测试条件,利用气相色谱建立了丁二酸二甲酯、丁二酸单甲酯和甲醇的标准曲线。在测试确认模拟混合样品的分析精度的基础上,分析了丁二酸酯化反应液样品中有机组分浓度。分析结果表明,该方法快速、准确、灵敏度高、重复性好,相对标准偏差(RSDs,n=7)在2%以内,能满足丁二酸酯化反应过程特性研究的分析要求。     

丁二酸单乙酯酰氯的合成和表征

以丁二酸单乙酯和氯化亚砜为原料合成丁二酸单乙酯酰氯。探讨了原料配比、反应温度和反应时间对反应的影响。最佳反应条件为:氯化亚砜∶单酯=1.6∶1(摩尔比),反应温度43℃,反应时间3 h,产率为95%。与文献比较,反应温度降低了10℃,产率提高了6个百分点。     

PVA与丁二酸酯化淀粉共混膜的力学性能

制备了不同改性程度的丁二酸酯化淀粉,并与聚乙烯醇（PVA）以溶液共混法制备了丁二酸酯淀粉/PVA共混膜,通过X射线衍射仪表征共混膜与酯化膜的结构,通过扫描电子显微镜观测其表面结构,并测试了共混膜的力学性能。结果表明,丁二酸酯化改性程度、PVA分子结构以及酯化淀粉/PVA的共混比对共混膜的力学性能有影响;随着改性程度的增加,共混膜的断裂强度及断裂伸长率均增大;随着PVA聚合度与醇解度的增大,共混膜的断裂强度及断裂伸长率均增大;随着淀粉含量的增加,共混膜的断裂强度先减小后增大,断裂伸长率逐渐减小;当共混比为50:50时,断裂强度最小。     

树脂催化剂催化生物法丁二酸预酯化工艺研究

采用自主开发的强酸型阳离子树脂催化剂进行市售生物法丁二酸酯化技术研究.利用丁二酸酯化后气质分析方法分析了市售生物法制备的丁二酸组成,并研究了预酯化实验中催化剂投放量、醇酸比、甲醇带水等操作条件对丁二酸预酯化反应的作用影响,考察了自主开发的树脂催化剂稳定性及活性.结果表明:自主开发的树脂催化剂具有较好的杂质耐受性,具有良...     

树脂催化剂催化生物法丁二酸双酯化工艺研究

采用自主开发的强酸型阳离子树脂催化剂进行对市售生物法丁二酸双酯化反应技术进行研究.首先对生物法丁二酸预酯化反应后的产品进行分离,分离后产品采用自主研发的树脂催化剂进行双酯化反应,研究了双酯化反应过程中,醇酸比、空速、反应温度及压力等操作条件对丁二酸双酯化反应的影响.考察了自主开发的树脂催化剂稳定性及活性,研究发现自主开...     

乙酸与甲醇的催化酯化

Esterification of methyl alcohol with acetic acid catalysed by Amberlyst-15 (cation-exchange resin) was carried out in a batch reactor in the temperature ranging between 318-338 K, at atmospheric pressure. The reaction rate increased with increase in catalyst concentration and reaction temperature, but decreased with an increase in water concentration. Stirrer speed had virtually no effect on the rate under the experimental conditions. The rate data were correlated with a second-order kinetic model based on homogeneous reaction. The apparent activation energy was found to be 22.9kJmol-1 for the formation of methyl acetate. The methyl acetate production was carried out as batch and continuous in a packed bed reactive distillation column with high purity methyl acetate produced.     

乙二醇铝催化酯化法合成聚丁二酸乙二醇酯

聚丁二酸乙二醇酯(PES)具有优异的力学性能和生物降解性能,在可生物降解塑料领域具有广泛的应用前景。以乙二醇铝为催化剂,催化丁二酸和乙二醇直接酯化缩聚合成了高分子量聚丁二酸乙二醇酯(PES)。采用FT-IR和1H-NMR对催化剂和合成聚合物的结构进行了表征,系统分析了催化剂浓度、聚合反应温度和时间对聚合反应的影响。经常压酯交换后获得的预聚体,在240℃条件下,缩聚4 h后,合成PES的特性黏数[η]可达到0.684 dL/g,重均分子量Mw和数均分子量Mn分别可以达到78632和47945,相对分子质量分布系数PDI值为1.64。乙二醇铝体系中获得的PES聚合物分子量与商业锑系和钛系催化体系中合成聚合物分子量相当,具有广泛工业化应用前景。     

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.     

Kinetic Investigation of Reaction Between Colemanite Ore and Methanol

In the field of industry, it is very important that boron compounds are produced from boron ores. The aim of this study was to investigate the dissolution kinetics with carbon dioxide of colemanite in methanol medium in a pressure reactor and to derive an alternative process for producing boron compounds. Reaction temperature, stirring speed, solid/liquid ratio, pressure, and particle size were selected as parameters for the dissolution rate of colemanite. It was found that the dissolution rate increased with increase in pressure and reaction temperature, and with decrease in particle size and solid/liquid ratio. No effect of stirring speed was observed on conversion. The dissolution kinetics of colemanite were examined using both heterogeneous and homogeneous reaction models, and it was determined that the reaction rate can be described by a second-order pseudo-homogeneous reaction model. The activation energy was found to be 51.4 kJ/mol.     

亚甲基丁二酸的生产与应用

本文介绍了亚甲基丁二酸的性质、生产工艺、应用及市场前景。     

10万吨／年低压甲醇羰基化法生产醋酸装置

本装置采用ＢＰ技术，利用甲醇低压羰基化法生产醋酸。其特点为原料合理，反应条件温和、生产效率高、成本低、产品质量高。该装置现已建成投产，是目前国内最大的醋酸生产装置。     

环孢菌素A与4-苯甲酰苯甲酸反应的研究

从合成环孢菌素A (CsA)免疫抗原的目的出发 ,研究了CsA与 4 苯甲酰苯甲酸 (BBa)在紫外光激发下的光化学反应。确定出最佳反应条件为 :n (CsA)∶n (BBa) =1∶1,光照距离为 9cm ,光照时间为 4h。产物CsA -BBa的收率达 5 1.9% ,其结构经UV、IR和HNMR谱的证实 ,可用于免疫抗原合成及抗体制备实验。     

气相色谱法测定甲醇汽油中甲醇含量方法研究

为了提高车用汽油中甲醇含量测定的准确度和精密度,以丁酮作为内标物,用气相色谱内标定量法测定甲醇汽油中的甲醇含量,并确定了最佳实验条件,同时对该方法的准确度和精密度进行了验证.结果表明在柱温60℃、进样口温度200℃、检测器温度250 ℃的条件下,色谱分离效果好,且测定结果具有检测范围宽和重复性好的特点,回收率达96%～...     

甲醇制芳烃反应的研究进展

简单介绍了甲醇制芳烃(MTA)目前所面临的困难,以及MTA反应所适用的催化剂ZSM-5及其优势。指出以HZSM-5做催化剂时,MTA反应的最优化反应条件,并综述了国内外目前对于ZSM-5催化剂的几种改性方法。并提出适用MTA的催化剂的开发方向。     

Relationship Between Methanol Permeability and Structure of Different Radiation‐Grafted Membranes

Styrene grafted and sulfonated poly(vinylidene fluoride) and poly(vinylidene fluoride‐co‐hexafluoropropylene) films are candidates as electrolytes in direct methanol fuel cells. Their behaviour in water, 1 and 3 mol dm^–3 aqueous methanol, and pure methanol were studied. According to SAXS results, water and methanol‐water solutions have similar effects on the membranes, i.e., the lamellar period increases and the ionic domains enlarge. Furthermore, differences in the ionic domain structures in pure methanol and water were observed. These structural changes together with dissimilar liquid uptakes in water and in methanol are reflected as changes in the conductivities. An increase in the SAXS intensity and changes in the Bragg distance of the ionic peak were observed in methanol compared to aqueous solutions. This may be related to the hydrophobicity of the CH₃ group on methanol. Dissimilarities in methanol permeability through the radiation‐grafted membrane can be related to structural differences in membranes observed with SAXS. Permeabilities were observed to be lower for the radiation‐grafted membranes compared to Nafion® 115, which compensates for the higher area resistance of the experimental membranes and thus improves their performance in a fuel cell.     

甲醇废料色素脱除方法的研究

对农药厂生产过程中副产的有色甲醇废料的脱色和提纯工艺进行了研究,结果表明用乙二胺四乙酸二钠为脱色剂,脱去甲醇中黄色再经蒸馏脱水后回收利用,达到了较为理想的效果,具有较好的经济效益和社会效益.     

Kinetic Investigation of Reaction Between Metallic Silver and Nitric Acid Solutions

In this study, the reaction kinetics between metallic silver and nitric acid solutions was investigated by taking into consideration the parameters of temperature, solid‐to‐liquid ratio, stirring speed, nitric acid concentration, particle size and addition of sodium nitrite. It was determined that the dissolution rate of the process increased with decreasing particle size and solid‐to‐liquid ratio, and increasing nitric acid concentration, reaction temperature and the amount of the sodium nitrite in the solution. In addition, it was observed that the stirring speed had more effect on the dissolution rate at low stirring speeds than at high stirring speeds. In the present study, the examination of shrinking core models of fluid‐solid systems showed that the dissolution of metallic silver in the nitric acid solutions was controlled by the reaction on the surface. A semiempirical model, which represented well the process, was developed by statistical methods. The activation energy of the process was found to be 57.66 kJ mol^–1.