Mechanistic model for kinetics of propene hydroformylation with Rh catalyst

Hydroformylation of propene to isobutyraldehyde and n‐butyraldehyde was studied in the kinetic regime in a semibatch stainless steel reactor at 85–115°C and 1–15 bar pressure in 2,2,4‐trimethyl‐1,3‐pentanediol monoisobutyrate solvent with rhodium catalyst cyclohexyl diphenylphosphine as a ligand, which showed lower normal/isometric aldehyde ratio (n/i) than previously studied triphenylphosphine. The rate was pressure and Rh concentration dependent. The regioselectivity was conversion independent; however, dependent on the ligand concentration, as higher ligand concentration promoted isobutyraldehyde formation. The influence of ligand concentration on regioselectivity was investigated. A kinetic model was proposed based on the mechanism of alkene hydroformylation and compared with experimental observations. Numerical data fitting was performed showing good agreement of reaction rates and regioselectivity with experimental data. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Synthesis of chloromethylstyrene‐tetraethyleneglycol dimethacrylate copolymer beads having various phenolic derivatives immobilized via amide bond and their antioxidation activity

Resins having phenolic derivatives were prepared by treating a resin (RAS‐4G), having benzylamino groups, with benzoic acids containing phenolic hydroxyl groups. The RAS‐4G was prepared by treating macroreticular chloromethylstyrene‐tetraethyleneglycol dimethacrylate (4G) copolymer beads with potassium phthalimide in N,N‐dimethylformamide, followed by reflux in an ethanol/hydrazine monohydrate mixture. 4‐Hydroxy benzoic acid, (2,4‐, 3,4‐, and 3,5‐)dihydroxy benzoic acids, 3,4,5‐trihydroxy benzoic acid, etc., were used as benzoic acids with phenolic hydroxyl groups. The antioxidation ability of the resins having phenolic derivatives was investigated against the generation of 1,4‐dioxane hydroperoxide. The resins showed high inhibition ability against the generation of hydroperoxide. In particular, the resin (RAS‐4G‐3,4‐DHBA) having two phenolic hydroxyl groups had the highest inhibition ability. The resins were found to act as radical scavengers during the generation of 1,4‐dioxane hydroperoxide by UV irradiation in the presence of oxygen. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2097–2104, 2005     

负载金属卟啉氧化异丙苯的研究

研制了异丙苯氧化制取二甲基节醇及过氧化异丙苯的负载型金属卟啉催化剂。其活性及选择性均较高,且易回收。金属卟啉类的活性顺序为：Cu＞Co＞Mn＞Fe＞Cr＞Pd＞Ni。卟啉环的中位苯基上的供电子基团有利于催化活性的提高。铜卟啉负载于不同载体的活性顺序为：TiO₂＞γ-Al₂O₃＞苯聚乙烯（交联）＞D261阴离子交换树脂＞无载体（均相）。加入有机含氮碱配位体可使铜外琳活性进一步提高,并降低其他金属卟啉的活性催化剂经十余次运转后活性下降约20％,此后无进一步明显下降。     

环己基苯基甲酮一步法合成的研究

考察了几种不同型号的沸石催化剂对苯与环己基酸反应合成环己基苯基甲酮的催化活性，在研究条件下，催化活性排序为：H－β型＞H－Y型＞HZSM－5型；用L16（4^5）正交表设计安排了实验，优化了以H－β型沸石为催化剂的反应条件，在最优反应条件下，环己基苯基甲酮收率为12．8％，并对催化剂寿命作了初步研究。     

Oxidative stability of polyunsaturated fatty acids: effect of squalene

The propensity of polyunsaturated fatty acids (PUFAs) to undergo oxidation plays an important role in the integrity of biological membrane and lipid containing foods. The ability of squalene (SQ), a naturally occurring dehydrotriterpene present in animal and plant tissues, to protect linoleic, linolenic, arachidonic and docosahexaenoic acids against temperature‐dependent autoxidation and UVA (ultraviolet A, 320‐380 nm) mediated oxidation was assessed. The oxidation of PUFAs was protected in varying degrees, with highest protection observed for linolenic, arachidonic and docosahexaenoic acids. Linoleic acid was less protected. At a molar ratio of 7:1 (PUFA:SQ) the inhibition of the oxidation process was 22% in the presence of linoleic acid and about 50% in presence of the other PUFAs tested. The different protection exerted by SQ against PUFAs with different degrees of unsaturation may be accounted for by the higher stability of octadecadienoic acid hydroperoxide isomers compared with respective PUFA hydroperoxides. Observing mild UVA‐mediated oxidation and the temperature‐dependent autoxidation reactions we found similarities in the oxidation pattern and the protection exerted by SQ. These findings suggest that the reaction of autoxidation is predominant and SQ acts mainly as peroxyl radical scavenger.     

异丙苯氧化的研究进展

异丙苯氧化反应在石油化学工业中有着重要的地位,主要对国内外异丙苯氧化所用的催化剂体系及反应机理进行了总结和综合性评述,并展望了该领域今后的研究方向。     

柴油催化氧化脱硫的研究

用溶胶-凝胶法制备HPWA/SiO2催化剂,用于直馏柴油进行了脱硫实验。实验考察了催化剂用量(以催化剂的质量相当于模型溶液的质量分数表示),O/S摩尔比(叔丁基过氧化氢与硫含量的摩尔比),反应温度和反应时间对脱硫效果的影响,得出最佳反应条件为催化剂用量5%,O/S摩尔比为7,反应温度为70℃,反应时间为2 h。实验结果表明该催化剂有很好的催化氧化作用,氧化后产物经过溶剂抽提,可将硫含量从350μg/g降到100μg/g。达到了国家标准。     

[BMIm]Br离子液体辅助HZSM-5催化乙酸环己酯高选择性水解反应

为提高HZSM-5催化乙酸环己酯水解反应生成环己醇的选择性,筛选得到了离子液体[BMIm]Br助剂。发现[BMIm]Br可抑制乙酸环己酯热分解副反应的发生,大幅度提高环己醇选择性。并且,[BMIm]Br可与HZSM-5发生离子交换反应,释放出的H⁺可促进乙酸环己酯水解反应的发生。在优化的条件下,[BMIm]Br辅助HZSM-5催化乙酸环己酯水解反应转化率为87.5%,环己醇选择性为97.3%。考察了[BMIm]Br和HZSM-5的重复使用性。前者具有较好的稳定性,而HZSM-5活性随循环使用的次数增加而下降。这是由于HZSM-5的骨架铝含量在反应中逐渐降低,导致Br?nsted酸中心数量减少,因此其催化活性逐渐降低。     

氢过氧化大豆油还原制备羟基大豆油

用亚硫酸钠还原氢过氧化大豆油制备羟基大豆油,并考察了溶剂种类,溶剂浓度,温度,还原剂亚硫酸钠量及还原时间对反应的影响.在实验条件下,最佳工艺条件为：15℃、以88.2 ％（V/V体系）的乙醇为溶剂、n（Na2SO3）∶n（-OOH）=1.2∶1、反应1.5h.氢过氧化大豆油的转化率达95.8％.     

Synthesis of a fatty tetrahydroxyamide using peroxygenase from oat seeds

Prior work has shown that oat (Avena sativa) seeds are a rich source of lipase and peroxygenase. Partial epoxidation of the isobutyl amide derivative of α-linolenic acid with peroxygenase gave N-i-butyl-9, 10–15, 16-diepoxy-12(Z)-octadecenamide, a diepoxide product in which the epoxides reside only at the formerly external double bond positions. No amide hydrolysis occurred during the epoxidation procedure. Hydrolysis of the diepoxide gave N-i-butyl-9, 10,15,16-tetrahydroxy-12 (Z)-octadecenamide, a polyol derivative with relatively high polarity, potentially useful in developing new materials from fats and oils.