Direct ethoxylation of fatty methyl ester over Al-Mg composite oxide catalyst

For the purpose of estimating the reaction mechanism of the direct ethoxylation of a fatty ester in the presence of an Al-Mg composite oxide catalyst, a labeled fatty methyl ester C₁₁H₂₃CO¹⁸OCH₃ containing ¹⁸O isotope was synthesized and directly ethoxylated. The product was evaluated by gas chromatography-mass spectrometry (GC-MS). The GC-MS spectra showed that the ¹⁸O isotope label was present only in the methoxy group at the molecular end of the ethoxylated fatty methyl ester. This supports the reaction mechanism of coordination anionic polymerization where the bond between the acyl and methoxy groups of the fatty methyl ester molecule was broken, caused by the bifunctional effect of the acid-base active sites; an intermediate chemisorption species was formed; and then ethylene oxide was addition-polymerized sequentially, in parallel.     

Separation of kinetics and mass-transfer in a batch alkoxylation reaction

The quantitative aspects of the role of interfacial mass-transfer and reaction kinetics in ethoxylation of lauryl alcohol were examined in a batch recirculation reactor. The liquid droplets falling through a gas column were obtained by utilizing a recirculation loop and a set of spray nozzles. The CO₂/NaOH reaction was employed to characterize the interfacial area. The alkoxylation reaction was studied at temperatures between 124°C and 171°C, at catalyst levels between 0.09 and 0.50 weight percent and at ethylene oxide partial pressures between 68 kPa and 204 kPa. A model was developed which permits the prediction of reactor performance at various operating conditions. The mass-transfer during free fall dominates the interfacial mass-transfer and the contributions during the drop formation and coalescence stages are small. The rate of ethylene oxide (EO) addition to lauryl alcohol was constant during the batch run, indicating similar activity for the unreacted lauryl alcohol and the lauryl alcohol ethoxylated to varying extents. The rate of ethoxylation is first-order in both catalyst and ethylene oxide concentrations. The liquid-phase reaction kinetics and interfacial mass-transfer occur in series, with kinetics dominating the overall ethoxylation rate. As expected, an increasing role of mass transfer is observed at higher temperatures, and/or higher catalyst concentrations where the kinetic rate becomes significantly high. The intrinsic activation energy for the ethoxylation of lauryl alcohol is 55.2 kJ/mole.     

国内外AE／AES生产现状及市场分析

介绍国内外脂肪醇聚氧乙烯醚(AE)和脂肪醇聚氧乙烯醚硫酸盐(AES)的生产现状及供需情况.2003年全球AE的总产能为391.7万t/a,总产量为155.8万t,总消费量为148.3万t;AES的总产能为377.5万t/a,产量约为300万t,消费量约为90万t.2004年我国AE的产能已超过50万t/a,但产量只有15万t,消费量为30.5万t;AES的总产能为37.95万t/a,产量为14万t,市场需求约10万t.最后补充介绍乙氧基化的技术进展.     

Effects of branching upon some surfactant properties of sulfated alcohols

A study was undertaken to determine the surfactant properties of various sulfated alcohols. Most notably, the Krafft point and the ability to emulsify decane were studied. A series of sulfated Guerbet alcohol and Guerbet alcohol alkoxylate sulfates with 16 carbon atoms and an analogous series based upon cetyl alcohol, a linear C₁₆, were studied as hydrophobes.     

A comparison of the ethoxylation of a fatty alcohol,fatty acid,and dimethiconol

Knowing that dimethiconols or silanols condense under acid or alkaline catalysis, a study was undertaken to determine if these compounds could be successfully ethoxylated under conditions similar to those used to ethoxylate fatty alcohols and acids. It was anticipated that the condensation reaction would take precedent over ethoxylation reaction. We determined that ethoxylation reaction occurs preferentially to condensation reaction. In addition, kinetics of ethoxylation are similar to kinetics observed when fatty alcohols are ethoxylated. This reaction gives rise to a new class of hydrolyzable silicone compounds that have applications in industrial as well as in personal-care products.     

传统醇醚的生产工艺技术提升

从产品合成、生产装置、催化剂类型、产品EO分布和游离醇含量以及下游衍生应用等方面介绍了近些年我国传统醇醚工艺技术的升级与进步。     

烷氧基化法一步合成丙烯酸乙氧基乙酯

采用镁铝固体催化剂催化环氧乙烷开环并插入丙烯酸乙酯(EA)的酯基中一步合成丙烯酸乙氧基乙酯(EEA),研究了催化剂中镁铝金属阳离子比例、催化剂焙烧温度等对催化剂活性的影响,采用SEM分析了催化剂形貌特征,经FTIR表征确认目标产物EEA结构。同时优化了烷氧基化法合成丙烯酸乙氧基乙酯的工艺条件。研究结果表明:在n(Al3+)/n(Mg2+)=0.8、焙烧温度为500℃的条件下,制备的催化剂活性最高;丙烯酸乙酯与环氧乙烷摩尔比为3∶1、反应温度130℃、催化剂用量为原料总质量1.5%的条件下,EO转化率接近70%,EEA选择性为57.59%,DEEA选择性为25.29%,TEEA选择性为11.54%。     

乙氧基化催化剂的研究进展

聚氧乙烯型非离子表面活性剂在表面活性剂行业及精细化工领域占有重要地位,其主要来源是乙氧基化产物。乙氧基化催化剂的研究进展将是推动非离子表面活性剂行业技术进步的重要因素。结合近年来国内外相关的研究工作,综述了乙氧基化催化剂的研究进展,对各类催化剂的催化性能和机理进行了分析,为以后乙氧基化催化剂的研究方向提出了建议。     

降低脂肪醇聚氧乙烯醚产品中游离环氧乙烷含量的研究

乙氧基化生产过程中,通过正交试验,找出最优工艺条件,在固定投料量的基础上,调整催化剂用量,增加熟化工艺,延长气提时间,降低产品中游离环氧乙烷（EO）含量,使得下游磺化生产中二恶烷的含量处于较低水平。     

聚氧乙烯醚的物化性能应用及乙氧基反应技术的现状

详细介绍了聚氧乙烯醚的物化性能，包括水溶性，润湿性，分散性，洗涤性，乳化性，生物降解等及其在纺织，洗漆印染，油墨，涂料，金属清洗等行业中的应用，并概述了国内外乙氧基反应工艺路线的现状进行比较。