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61.
Anders?Falk?VikbjergEmail author Lifeng?Peng Huiling?Mu Xuebing?Xu 《Journal of the American Oil Chemists' Society》2005,82(4):237-242
The possibilities of producing structured phospholipids between soybean phospholipids and caprylic acid by lipase-catalyzed
acidolysis were examined in continuous packedbed enzyme reactors. Acidolysis reactions were performed in both a solvent system
and a solvent-free system with the commercially immobilized lipase from Thermomyces lanuginosa (Lipozyme TL IM) as catalyst. In the packed bed reactors, different parameters for the lipase-catalyzed acidolysis were elucidated,
such as solvent ratio (solvent system), temperature, substrate ratio, residence time, water content, and operation stability.
The water content was observed to be very crucial for the acidolysis reaction in packed bed reactors. If no water was added
to the substrate during reactions under the solvent-free system, very low incorporation corporation of caprylic acid was observed.
In both solvent and solvent-free systems, acyl incorporation was favored by a high substrate ratio between acyl donor and
phospholipids, a longer residence time, and a higher reaction temperature. Under certain conditions, the incorporation of
around 30% caprylic acid can be obtained in continuous operation with hexane as the solvent.
Presented at the 95th American Oil Chemists' Society Annual Meeting and Expo in Cincinnati, Ohio, May 10, 2004. 相似文献
62.
2-[N-甲基-N-(2-吡啶基)氨基] 乙醇制备条件的优化 总被引:1,自引:0,他引:1
2-[N-甲基-N-(2-吡啶基)氨基]乙醇是合成罗格列酮(Rosighitazone)的一种中间体,罗格列酮是新型噻唑烷二酮类胰岛素增敏剂,通过两轮优化设计,实验室小试得到了较好的反应条件.为工业化生产提供了基础数据。 相似文献
63.
Biomass pyrolysis in a circulating fluid bed reactor for the production of fuels and chemicals 总被引:3,自引:0,他引:3
An approach for biomass flash pyrolysis in a circulating fluid bed (CFB) reactor with continuous solids regeneration is described in this study. The unit is capable of performing conventional and catalytic biomass pyrolysis with the proper solid selection. The production of improved quality liquid products in a direct step through catalytic pyrolysis is investigated in this work. Both conventional and catalytic biomass pyrolysis can be effectively performed in this CFB unit. Flash pyrolysis conditions were achieved and liquid product yields of ∼70 wt% (on biomass feed) were obtained. The effect of specific operating variables including the type of inorganic solid material and the solid/biomass ratio was established on the final liquid product quality and yield. Solid materials considered included silica sand, a commercial fluid catalytic cracking catalyst and a ZSM-5 additive. Catalytic biomass pyrolysis generally leads to the production of additional water, coke and gases compared to conventional pyrolysis. However, the obtained liquid product quality and composition is improved. 相似文献
64.
Tiina Komulainen Mauri Sourander Sirkka-Liisa Jms-Jounela 《Computers & Chemical Engineering》2004,28(12):2611-2619
65.
66.
本文分析了70年代以来国际化工设备朝单系列大型化及高压力的发展趋势,以及高效能、低能耗的要求,在这个基础上介绍当前国内外化工设备新设备研制及旧设备改造的进展情况。最后提出对广州市、广东省在“八·五”期间化工设备技术的展望:乙烯设备国产化与旧设备的更新换代,进行技术改造。 相似文献
67.
Comparison of a contactor catalytic membrane reactor with a conventional reactor: example of wet air oxidation 总被引:1,自引:0,他引:1
Sylvain Miachon Victor Perez Gabriel Crehan Eddy Torp Henrik R der Rune Bredesen J. -A. Dalmon 《Catalysis Today》2003,82(1-4):75-81
A wet air oxidation reaction was carried out in a gas/liquid catalytic membrane reactor of the contactor type. The oxidation of formic acid was used as a model reaction. The mesoporous top-layer of a ceramic tubular membrane was used as catalyst (Pt) support, and was placed at the interface of the gas (air) and liquid (HCOOH solution) phases.
A similar reaction was carried out in a conventional batch reactor, using a steering rate high enough to avoid gas-diffusion limitations, and exactly identical conditions than for the CMR (amount of catalyst, pressure, etc.). At room temperature, the CMR showed an initial activity three to six times higher than the conventional reactor. This activity increase was attributed to an easier oxygen access to the catalytic sites. Nevertheless, the catalytic membrane gradually deactivated after a few hours of operation. Different deactivation mechanisms are presented. 相似文献
68.
现代化工生产规模呈大型化趋势,要求更有效的传热元件来消除“放大效应”。简述了热管的工作原理及其在化工反应器中的应用。 相似文献
69.
烯(醚)醛一步法合成异戊二烯技术开发—基础理论研究进展 总被引:1,自引:0,他引:1
本文介绍了烯(醚)醛一步法合成异戊二烯技术开发中,基础理论研究工作的进展,其中包括化学热力学、化学动力学、再生烧炭本征动力学和扩散动力学等理论研究。并针对该反应特征进行了化学反应规律和流动传递规律的研究。建立了流化床反应器数模和流化床再生器数模,为工程技术开发提供理论依据。 相似文献
70.