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51.
国内干法脱硫剂工业应用现状 总被引:3,自引:0,他引:3
纪容昕 《化学工业与工程技术》2002,23(1):29-33
介绍了国内主要的干法脱硫过程以及脱硫剂的工业应用情况和发展趋势 ,比较了现有国内不同脱硫剂的使用情况、主要性能、适用条件和经济技术指标等 ,认为选择合适的脱硫剂应考虑其各自特点及影响因素 相似文献
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By adding a small amount of clay into poly(p‐phenylene sulfide) (PPS)/polyamide 66 blends, the morphology was found to change gradually from sea–island into cocontinuity and lamellar supramolecular structure, as increasing of clay content. Clay was selectively located in the PA66 phase, and the exfoliated clay layers formed an edge‐contacted network. The change of morphology is not caused by the change of volume ratio and viscosity ratio but can be well explained by the dynamic interplay of phase separation between PPS and PA66 through preferential adsorption of PA66 onto the clay layers and through layer–layer repulsion. This provides a means of manipulating the phase morphology for the immiscible polymer blends. The mechanical and tribological properties of PPS/PA66 blends with different phase morphologies (different clay contents) were studied. Both tensile and impact strength of the blends were found obviously increased by the addition of clay. The antiwear property was greatly improved for the blends with cocontinuous phase form. Our work indicates that the phase‐separating behavior of polymer blends contained interacting clay can be exploited to create a rich diversity of new structures and useful nanocomposites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
54.
黄磷尾气净化脱除磷化氢、硫化氢中试试验 总被引:7,自引:0,他引:7
采用自制的催化剂JC-4,设计出碱洗-催化氧化工艺对黄磷尾气进行深度净化处理。中试试验结果表明:常压、100℃、尾气流量为36~50 m3/h、氧气体积分数为1.2%~1.5%时,PH3的脱除率接近100%,出口质量浓度低于1.0 mg/m3;碱洗单元可以除去90%的H2S,经过催化氧化单元可以进一步脱除H2S,净化效率接近100%,出口质量浓度低于1.0 mg/m3;催化剂经100~200 h需要再生,400 h后需要活化,再生和活化处理后的催化剂性能良好。 相似文献
55.
玻纤增强聚苯硫醚复合材料的增韧研究 总被引:1,自引:0,他引:1
针对玻纤增强聚苯硫醚材料韧性差的问题,对聚苯硫醚傲璃纤维复合体系的增韧进行了研究,考察了玻纤、改性聚合物、有机超细粒子对复合材料力学性能的影响。采用基体增韧(预增韧)与有机超细粒子增韧技术,在保持复合材料拉伸强度和模量的同时,较大地提高了冲击强度,获得了综合力学性能优异的纤维增强聚苯硫醚材料。 相似文献
56.
Graft copolymerization of acrylic acid (AA) onto polyphenylene sulfide (PPS) nonwoven initiated by low temperature plasma was studied. The effects of various conditions on graft reaction and the grafting rate were investigated. SEM images showed that PPS nonwoven was grafted, and the graft copolymerization only occurred on the surface of PPS. It may be due to the chain transference going with the graft copolymerization. It was found that with the increasing of plasma power, treatment time, space between electrodes, monomer concentration, and temperature of graft polymerization, the grafting rate increased at first, went to the top, and then decreased. The PPS nonwoven surface graft reaction could be optimized by the following processing conditions: 120 s of plasma treatment time, 50 W of plasma power, 1.5 cm of space between electrodes, 30% (w/w) of monomer concentration, and 50°C of temperature of graft polymerization. Measurement of XPS showed that the peak of C1s of graft polyacrylic acid was existed, and the peak area increased with the increase of the grafting rate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5884–5889, 2006 相似文献
57.
P. E. Højlund Nielsen Karsten Pedersen J. R. Rostrup-Nielsen 《Topics in Catalysis》1995,2(1-4):207-221
The kinetics of hydrocarbon synthesis over sulfide-based catalysts was studied. It appears that the formation of methane follows another reaction path than that of higher hydrocarbons. This might explain the very high selectivities for ethane and propane as compared with conventional Fischer-Tropsch catalysts. Reference is made to testing of the catalysts at industrial conditions. 相似文献
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59.
Polycrystalline (PbS)1.14(TaS2)2, a misfit layer sulfide, was used as cathodic material for lithium secondary battery. One molar LiClO4 in propylene carbonate (PC) was used as electrolyte. The cell could be galvanostatic discharged down to x = 4.6 [Lix(PbS)1.14(TaS2)2] when the current density was 65 μA cm−2 and the cell was cycled more than 100 times between 3.5 and 1.5 V at a current density of 260 μA cm−2. Lattice expansion increased linearly with lithium content and was less than that reported for the Li/TaS2 system. Chemical diffusion coefficients were determined by a modified version of the galvanostatic intermittent titration technique and they were fairly constant in the composition range 0.2 < x < 1, and an average value of 8.1 × 10−11 cm2 s−1 was calculated. Sodium intercalation was also accomplished, but the uptake of this ion resulting in a significant lattice expansion compared with that observed for lithium ions. Moreover, a similar dependence of the sodium chemical diffusion coefficient on the composition was observed with an average value of 1.4 × 10−10 cm2 s−1, somewhat higher than that of lithium ion. We believe that differences in lattice expansion may be responsible for the differences found in the chemical diffusivity values. 相似文献
60.
FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation of marmatite was strongly depressed, while that of chalcopyrite was only slightly depressed, over a wide range of pH values when FCLS was used as depressant in the presence of Butyl Xanthate (BX). The adsorption of BX onto chalcopyrite or marmatite takes place over a wide pH range. The adsorption density of BX on chalcopyrite and marmatite decreases as the pH increases. The adsorption density of FCLS onto marmatite is greater than the adsorption density onto chalcopyrite. The zeta potentials of chalcopyrite and marmatite become more negative due to the addition of xanthate and FCLS. 相似文献