Na2WO4/1,2,3,4-丁烷四羧酸催化氧化环己烯合成己二酸

在无有机溶剂、无相转移剂的条件下,以E(H2O2)=30％为氧源,采用原位合成的Na2WO4／1,2,3,4-丁烷四羧酸／H2O2过氧钨酸络合物为催化剂,催化氧化环己烯合成己二酸。考察了酸性配体1,2,3,4-丁烷四羧酸的用量、反应温度和反应时间对反应的影响。当n(1,2,3,4-丁烷四羧酸)：n(Na2WO4)=4：1、n(Na2WO4)：n(环己烯)：n(H2O2)=1：40：176、水浴控制温度(70～90℃)时,反应8h,己二酸分离产率高达85．1％。催化剂重复使用至第5次,己二酸产率仍分别可达80．4％(回流控温)和80．2％(水浴控温70～90℃)。     

三羟甲基丙烷酯的合成及其抗乳化性能研究

以三羟甲基丙烷(TMP)及不同类型的脂肪酸为原料，合成了具有抗乳化性能的三羟甲基丙烷酯系列产品。考察了该系列产品抗乳化性能，确定了具有较佳的抗乳化性能的产品配方：即用油酸-庚酸-己二酸组合与TMP反应，当n(TⅧ)／n(混酸)=1／2．9，m(油酸)／m(庚酸 油酸)=80％，n(油酸 庚酸)／n(己二酸)=6时，所得复合酯具有较好的抗乳化性能。     

磁性纳米SO4^2-／Fe3O4-ZrO2固体超强酸催化合成己二酸二正辛酯

利用磁性对纳米固体超强酸组合，制备出磁性纳米SO4^2-／Fe3O4-ZrO2固体超强酸催化剂，并用TEM、IR、Hammett指示剂检测磁性纳米固体超强酸催化剂性能。将其用于己二酸二正辛酯（DOA）的合成反应中。得到最佳反应条件为负压下，反应温度155℃，n（正辛醇）：n（己二酸）=3．2：1，反应时间2h，w（催化剂）=1．5％，己二酸的转化率达99％。利用催化剂的磁性可将纳米颗粒催化剂迅速分离，回收率达93．8％，并能重复使用。     

己二酸二-(2-羟基-3-磺酸钠)丙酯的合成研究

研究了己二酸二-(2-羟基-3-磺酸钠)丙酯，探讨了反应物物质的量之比、反应时间、催化剂、反应温度等对己二酸转化率的影响，优化实验条件为：四氢呋喃作溶剂，投料比n(己二酸）：n(氢氧化钠）=1∶2.4∶2，十六烷基三甲基溴化铵作相转移催化剂，反应温度68—70℃，反应时间12h。终产品组成通过IR、EA、^1HNMR进行了确认。     

Cr2O7^2-／Cr^a＋和Ce^4＋／Ce^3＋电解液作媒质间接合成对甲氧基苯甲醛

在高剪切混合乳化机搅拌下，通过对Cr2O7^2-／Cr^a 和Ce^4 ／Ce^3 两种媒质间接合成对甲氧基苯甲醛槽外反应的研究，得到合成对甲氧基苯甲醛的优选条件分别为：原料配比n(Cr2O7^2-)：n(p-CH3O-C6H4-CH3)=1：6，反应温度80℃，反应时间10min，对甲氧基苯甲醛反应收率90．5％：原料配比n(Ce^4-)：n(p-CH3O-C6H4-CH3)=1：1，反应温度30℃，反应时间6min，对甲氧基苯甲醛反应收率97．1％。结果表明，Ce^4 ／Ce^3 做媒质产品时．空效率较低，这是Ce^4 ／Ce^3 媒质存在的本质缺陷：而Cr2O7^2-/Cr^3 做媒质产品时一空效率提高近2倍，显著地增加产品的产量，提高了经济效益。     

用SnO／TiO2／ZnO作催化剂合成DOP的研究

用SnO／TiO2／ZnO作催化荆合成邻苯二甲酸二(2-乙基)己酯(DOP)。当n(苯酐)：n(2-EH)：1：(2．3～2.4)，反应温度200～220℃，催化剂用量为反应物总量的0．2％～0．3％时．可得到优级品的DOP。     

SO42-/Si-Zr-CLR固体超强酸催化合成己二酸二庚酯

将硅锆交联粘土固体超强酸(SO4^2-／Si-Zr-CLR)用于己二酸二庚酯的合成反应中。最佳反应条件为：反应温度150℃,庚醇：己二酸(摩尔比)=2．8：1,反应时间2．5h,ω(催化剂)=1．2％,己二酸的转化率达96．8％。催化剂和产品易于分离。并能重复使用。     

连续酯化制备1，6-己二酸二甲酯

以DNW-I型强酸型阳离子交换树脂（DNW-I型催化剂）为催化剂,己二酸和甲醇为原料,经间歇酯化和连续酯化反应后通过精馏可制备选择性为100％的1,6-己二酸二甲酯。结果表明,当DNW-I型催化剂用量为5％（以己二酸计,m／m,下同）时,己二酸间歇及连续酯化后转化率分别大于68％和98％。优化实验条件为：间歇酯化：催化剂用量5％,凡（甲醇）：n（己二酸）=2．5：1．0,反应温度80-85℃,反应时间4h：连续酯化：间歇酯化产物进料为30～70mL／h,甲醇进料为95-210mL／h,醇酸摩尔比〉60。     

SO2-4/TiO2-MoO3催化合成苹果酸酯-B

以固体超强酸SO^2-4／TiO2-MoO3为多相催化剂，对以乙酰乙酸乙酯和1，2-丙二醇为原料合成苹果酸酯-B的反应条件进行了研究。实验表明固体超强酸SO^2-4／TiO2-MoO3是合成苹果酸酯-B的良好催化剂，最佳反应条件为：n(乙酰乙酸乙酯)：n(1，2-丙二醇)为1：1．5，催化剂用量为反应物料总质量的1．5％，环己烷为带水剂，反应时间1．0h，反应温度88～116℃，苹果酸酯-B收率达74．0％。     

SO4^2-／TiO2-MoO3-La2O3催化合成环己酮1，2-丙二醇缩酮

报道了以固体超强酸SO4^2-／TiO2-MoO3-La2O3为多相催化剂，通过环己酮和1，2-丙二醇反应合成了环己酮1，2-丙二醇缩酮，探讨SO4^2-／TiO2-MoO3-La2O3对缩酮反应的催化活性，较系统地研究了酮醇量比，催化剂用量，反应时间诸因素对产品收率的影响。实验表明：SO4^2-／TiO2-MoO3-La2O3是合成环己酮1，2-丙二醇缩酮的良好催化剂，在n(酮)：n(醇)=1：1．5，催化剂用量为反应物料总质量的1．0％，环己烷为带水剂，反应时间1．0h的优化条件下，环己酮1，2-丙二醇缩酮的收率可达84．2％。     

Application of a mathematical model for the polyesterification process based on mixtures of fumaric acid and adipic acid without catalyst

The production of unsaturated polyesters based on mixtures of fumaric acid and adipic acid for different proportions without added catalyst was studied. The progress of the polyesterification was followed by determining the amount of water produced during the reaction. The kinetic parameters (reaction order n, activation energy E, frequency factor k₀) of the polyesterification were determined and it was found out that n = 3 in all cases, while E and k₀ increased by increasing amount of fumaric acid in the initial mixture of the reaction. A mathematical model for the polyesterification based on the production parameters (e.g. the heating program) and on the kinetic parameters was used and very good correlation was found between the corresponding pair of curves of water produced during the polyesterification, which were determined experimentally and theoretically (by calculating). With regard to the properties of the final product it was found out that its viscosity and its slight yellow colour increased by increasing the amount of fumaric acid in the initial mixture of raw materials. General prospects for practical application of this method were also discussed.     

Synthesis of polyesters as binders for deinkable inks. II. Kinetics and mechanism of polyesterification between o-phthalic anhydride and neopentyl glycol in bulk at 200°C

The kinetics of the polyesterification in bulk at 200°C between o-phthalic anhydride and neopentyl glycol (2,2-dimethyl-1,3-propanediol) in a nonequimolecular ratio and in the absence of an external catalyst was investigated. The formation of the monoester and two dimeric compounds by uncatalyzed heating of o-phthalic anhydride with neopentyl glycol was virtually complete after dissolution of the anhydride. The data were analyzed statistically by a mathematical method due to Fradet and Maréchal for the estimation of the orders of reaction. This statistical adjustment of the data analysis supports the assumption that the kinetics of polyesterification in the absence of both the solvent and catalyst may be fitted to several orders of reaction over all the conversion. At first, our experimental data may be fitted to 3, or , or 2, etc., overall orders. The results establish that the overall kinetic order of the polyesterification depend upon the goodness of the experimental results and cannot be only selected by means of a correlation coefficient. If this last criterium is adopted, the polyesterification at low, medium, as well as at high conversions may be 3 as the most probable one, order one with respect to acid group concentration, and order two with respect to alcoholic group concentration, in agreement with Flory's predictions. A mechanism consistent with the most plausible kinetic results (I_m,n = 0.9990 and m, n = 1, 2) is proposed. It consists of a dimerization of the alcoholic groups followed by an attack of the acid to the dimer. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2409–2431, 1997     

The kinetics of polyesterification. I. Adipic acid and ethylene glycol

The polyesterification between adipic acid and ethylene glycol in nonequimolar ratios was investigated. The kinetic equations obtained were quite different from those obtained by Flory in equimolar systems. The kinetic equations obtained in this study were ?d[COOH]/dt = k[COOH][OH]² for uncatalyzed polyesterification and ?d[COOH]/dt = k[COOH]² for catalyzed polyesterification. The mechanism of the polyesterification of a dibasic acid and a glycol can only be explained by the dissociation effect of hydrogen ion from dibasic acid in glycol.     

Polyester polyols for polyurethanes from pet waste: Kinetics of polycondensation

The kinetics of polyesterification of the glycolyzed PET waste with adipic acid is reported. Glycolysis of PET waste was carried out with ethylene glycol at three different ratios of PET waste to glycol. The glycolyzed products could be readily polyesterified by reacting with adipic acid, to give polyester polyols with low acid number. Kinetics of polyesterification of the glycolyzed product made from 62.5% ethylene glycol (EG) and 37.5% waste were investigated further at different hydroxyl to carboxyl ratios. Reaction conditions were nonisothermal, comparable to the industrial process scheme consisting of two isothermal regions at 170° and 200°C. The kinetic results of the polyesterification of glycolyzed PET waste are compared to the polyesterification of pure diols, namely ethylene glycol and bis(hydroxyethyl) terephthalate (BHET) with adipic acid. The reactions follow second-order kinetics at 170°C and the rate of polyesterification of the mixed diol system from PET waste lies intermediate between those of the pure diols, namely, EG and BHET. Ethylene glycol exhibited the highest reactivity. At 200°C the kinetic plots of the mixed diols from PET waste were nonlinear, and thus the reaction may not follow second-order kinetics. The nonlinearity is explained in terms of the different reactivities of the different diol species in the reaction mixture. The polyester polyols, when cured with polymeric 4,4′ diphenyl methane diisocyanates, gave polyurethane rigid foams and elastomers.     

Synthesis of plasticizing polyesters of dimer acid and propane–diol

The polyesterification of dimer acid with propane–diol under different experimental conditions has been studied to obtain the optimum conditions for synthesizing the poly(propane–diol) dimerate plasticizers. The effect of varying molar ratio, temperature, and catalyst concentration on the course of the reaction, acid number, intrinsic viscosity, and molecular weight of the resultant polyester has been investigated. p-Toluene sulfonic acid (PTSA) was found to be an effective catalyst for the polyesterification reaction. The kinetics of polyesterification in the presence and absence of a catalyst has been found to follow the second-order rate equation in equimolar concentrations of the reactants. © 1993 John Wiley & Sons, Inc.     

超声波辅助合成己二酸

己二酸是一种重要的化工原料,利用高锰酸钾在超声波的辅助作用下氧化环己醇的方法制备己二酸,分别探讨了物料比、反应温度、反应时间等参数,得到最佳反应条件为:以NaOH的水溶液为溶剂,超声波功率为250W,物料比n(环己醇):n(高锰酸钾)=1:3.5,在75℃下反应,55min,然后将反应液浓缩、酸化。在此条件下,己二酸的产率高达84.7%,且实验安全、平稳、重现性好,是合成己二酸切实可行的绿色生产工艺。     

C_(36)二聚脂肪酸/聚乙二醇聚酯的制备及动力学研究

以C36二聚脂肪酸和聚乙二醇400为原料,缩聚得到一种新型高分子表面活性剂,适宜的工艺条件:在0.097 MPa下,n(二聚脂肪酸)∶n(聚乙二醇400)为1∶1.2,催化剂SnCl2(相对二聚脂肪酸质量分数为0.3%,反应温度200℃,反应时间6 h,酯化率达到98.11%。建立了SnCl2催化下,二聚脂肪酸与聚乙二醇缩聚反应的动力学模型,并采用改进的遗传算法,对动力学模型参数进行估算。结果显示,二聚脂肪酸与聚乙二醇400缩聚反应级数为0.998级,酯化反应活化能E=97.18 kJ/mol,指前因子A=1.947 9×109L/(mol.min),缩聚反应的Arrhenius方程为lnk=21.39-11.689/T。     

Synthesis of resins as alpha-alumina precursors by the Pechini method using microwave and infrared heating

A polymeric method based on the Pechini process was successfully used to synthesize alpha-alumina. Different resins have been prepared in order to compare the effect of the heating source (microwave or conventional IR radiation) during the polyesterification reaction, the importance of the starting aluminium salt and the ratios between reactants. The resin precursor and the product powders were fully characterized in order to investigate the polymer decomposition and the characteristic of the resulting alumina. It is concluded that the control of the ethylene glycol to citric acid ratio is important to obtain weak agglomerated particles, which are required to achieve soft porous precursors. Comparing with a conventional infrared source, the 2.45 GHz-microwave heating reduces the polyesterification reaction time to a great extent followed by a solid polymeric resin formation; however, the reaction mechanisms do not change. The best final alumina powder was synthesised by applying the microwave radiation to a precursor resin obtained from the thermal reaction of the aluminium lactate with small amounts of ethylene glycol as the polymerizant agent.     

Vibrofluidized Bed Drying of Adipic Acid

Adipic acid is a white crystalline solid and is the most industrially important of all aliphatic dicarboxylic acids. Drying is the principal unit operation after its crystallization. The acid has a tendency to agglomerate when moistened, due to its high cohesiveness. The fluidization regime does not occur and the particles cannot be adequately treated in a conventional fluidized bed. This article deals with the drying of adipic acid in a vibrofluidized bed. The equipment used in the drying tests was specially designed and constructed to maintain the fluidized regime of fine particles of moistened adipic acid. The drying curves presented the constant and the falling rate periods, yielding final moisture contents that depend mainly on the drying temperature. The quality of the dried acid was also verified by the crystals' granulometric analysis, which showed breakage of crystals for drying at higher air temperatures. Results showed to be satisfactory for drying adipic acid with moisture content up to 5.1% w.b. in the vibrofluidized bed, keeping a high degree of bed homogeneity and quality of the fluidized state.