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31.
磷钨杂多酸催化乙醇和乙酸酯化反应的研究   总被引:2,自引:0,他引:2  
以多孔钛片为支撑体,制备了磷钨杂多化合物薄膜化催化剂。在膜催化器上,考察了薄膜化催化剂对乙醇和乙酸合成乙酸乙酯的催化性能。结果表明,薄膜化催化剂显著提高了催化活性;当n(乙醇)∶n(乙酸)=1.5∶1,原料流量2.55mL/h;在反应温度为110℃时,乙酸乙酯产率可达97%,且薄膜催化剂的处理很方便,不污染环境。  相似文献   
32.
本文介绍了丙烯腈生产过程中影响杂质噁唑产生的因素,并对噁唑超标的处理方法进行了研究,成功地将侧线产品中噁唑的含量控制在10^-6之内。  相似文献   
33.
介绍了压缩机废油回收的原理、工艺及操作要点,达到了节油降耗的目的。  相似文献   
34.
This paper presents a mathematical model based on the reaction rate expressions to describe the displacement of methane conversion in the steam reforming. The effect of several parameters including weight hourly space velocity (WHSV), load-to-surface ratio, reaction pressure, hydrogen partial pressure in permeate side and reaction temperature were investigated. Simulation and experimental results showed that a conversion higher than 80% could be achieved in a palladium membrane reactor at reaction temperature of 500 °C relative to 850 °C in a conventional fixed bed reactor (FBR). Besides, the yield of CO (<2%) in membrane reactor was much lower than that (>50%) in the FBR, which indicated the significant depression of CO production in use of membrane reactor.  相似文献   
35.
Nanopowders of LaGaO3- and LaMnO3-based complex perovskites (P) and ceria-based fluorites (F) were prepared by mechanosynthesis. Compatible nanocomposites F + P and P + P with mixed ion and electron conducting (MIEC) properties were prepared and sintered at moderate temperatures up to dense ceramics. The obtained materials were studied by means of XRD, SEM, TEM, electrical conductivity measurements, temperature programmed (TP) reduction/oxidation and preliminary estimations of permeability were obtained. A new strategy based on the advantages of the mechanochemical ceramic approach is proposed to design multilayer ceramic membranes for CMR. Casting technology and one-step sintering were used for the production of thin film membranes with MIEC properties on porous substrates. The coarse fraction of as-milled powders from agglomerates with density 70% was used for the porous substrate, and fine fractions of aggregates with sizes <1 μm were used in preparation of composites for thin dense films. Ceria-based composites prepared by the Pechini route and/or mechanochemical method are proposed as materials for protecting thin films.  相似文献   
36.
An optimization strategy has been applied to describe the chemical composition at the furnace bottom in the Kraft recovery boiler of a pulp production process. The concentrations of each involved chemical species were calculated through an optimization approach, minimizing the Gibbs free energy of the system. Various systems were proposed and tested, assuming different chemical species and phases number. Because serious initialization problems were found at this stage for some of the proposed systems, an optimization heuristic method (PSO) was used for the first approach to the problem. Once the appropriate phases number and chemical species in the system were determined, the initialization problems disappeared and the use of a deterministic optimization method (SQP) became viable. The proposed approach has shown to be satisfactory to reproduce industrial data and also data reported in the open scientific literature.  相似文献   
37.
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.  相似文献   
38.
钯-银合金膜分离氢气的研究   总被引:1,自引:0,他引:1  
采用厚为50μm的Pd/Ag(23)合金膜进行了氢气渗透系数的测定和H_2/N_2混和气分离的研究,得出温度、压力、膜厚、进料气流量、膜的预处理和再活化及膜表面中毒等因素对氢气渗透的影响。分离H_2/N_2混和气可获得高纯氢气。  相似文献   
39.
Poly (vinyl butyral) (PVB) hollow fiber membranes were fabricated via thermally induced phase separation (TIPS). The effects of coagulation bath temperature (CBT) on the structure and performance of membranes were investigated in detail. The morphologies of the membranes were studied by scanning electron microscopy (SEM), the performances of water permeability, rejection, breaking strength and elongation were measured, respectively. The results indicate that all the membranes have the asymmetric morphology and the thickness of the skin layer decreases and the pore size of the outer layer increases with the increase of CBT. The permeability of membranes prepared at air gap 1.0 cm and take-up speed 0.253 m/s increases from 1.047×10-7 to 5.909×10-7 m3/(m2·s-kPa) with the CBT increasing from 20 ℃ to 40℃, and sharply increases to 35.226×10 7 m3/(m2.s.kPa)once the CBT arrives at 50 ℃. While the carbonic ink rejections have no significant decrease, totally exceed 98%, but that of acid-maleic acid copolymer greatly decreases with the increase of CBT. Both the breaking strength and elongation decrease with the increase of CBT.  相似文献   
40.
导磁体在汽车零件感应加热中的应用技术   总被引:1,自引:2,他引:1  
本文简单介绍了导磁体工作的基本原理,并给出在汽车零件大规模生产中所积累的导磁体应用的一些经验,以阐明如何更有效地使用导磁体。  相似文献   
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