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991.
NHD净化工艺应用领域 总被引:6,自引:0,他引:6
介绍氮肥厂、醋酸厂、甲醇厂在新建及改造过程中应用NHD法脱硫脱碳气体净化技术的过程和效果,进一步阐述了国外使用与NHD溶剂相同的净化技术在天然气处理、整体煤气化联合循环发电中对各种气体良好的选择吸收性能,以此证明NHD净化技术能适用于更广泛的气体净化过程。 相似文献
992.
993.
生产甲醇是山西焦炉气利用的有效途径 总被引:1,自引:1,他引:1
通过因地制宜的市场分析和技术经济分析 ,阐述了焦炉煤气制取甲醇是一条有效的化工利用途径 相似文献
994.
Fuel gas from a wood waste carbonization reactor 总被引:3,自引:0,他引:3
The production of fuel gas from wood wastes in a full scale carbonization reactor of simple design was studied. The production of methane and the approach to equilibrium to the water-gas shift reaction were experimentally correlated with the operating conditions. The heating value of the gas produced is comparable to that of typical air blown coal and biomass gasifiers, and may be improved by pre-drying the solid feed and by operating the reactor at lower temperatures. 相似文献
995.
Nanocomposite Ni/ZrO2-AN catalyst consisting of comparably sized Ni metal and ZrO2 nanoparticles is studied in comparison with zirconia- and alumina-supported Ni catalysts (Ni/ZrO2-CP and commercial Ni/Al2O3-C) for steam reforming of methane (SRM) and for combined steam and CO2 reforming of methane (CSCRM). The reactions are performed under atmospheric pressure with stoichiometric amounts of H2O and CH4 or (H2O + CO2) and CH4 at 1073 K. Under a wide range of methane space velocity (gas hourly space velocity of methane GHSVCH4 = 12,000–96,000 ml/(h gcat.), the nanocomposite Ni/ZrO2-AN catalyst always shows higher activity and stability for both SRM and CSCRM reactions. The two supported Ni catalysts (Ni/ZrO2-CP and Ni/Al2O3-C) exhibit fairly stable catalysis under low GHSVCH4 but they are easily deactivated under high GHSVCH4 and become completely inactive when they are reacted for ca.100 h at GHSVCH4 = 48,000 ml/(h gcat.). The CSCRM reaction is carried out with different H2O/CO2 ratios in the reaction feed while keeping the molar ratio (H2O + CO2)/CH4 = 1.0, the results prove that the nanocomposite Ni/ZrO2-AN catalyst can be highly promising in enabling a catalytic technology for the production of syngas with flexible H2/CO ratios (ca. H2/CO = 1.0–3.0) to meet the requirements of various downstream chemical syntheses. 相似文献
996.
997.
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
998.
999.
Yasushi Endo Sanae Hoshizaki Kenshiro Fujimoto 《Journal of the American Oil Chemists' Society》1997,74(9):1041-1045
Thirteen synthetic triacylglycerols (TAG) containing eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) were oxidized
in the presence of 2,2′-azobis(2,4-dimethyl-valeronitrile) (AMVN) and 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH)
as aqueous and nonaqueous radical initiators to investigate the influence of TAG structure and oxidation system on the oxidative
stability of TAG that contain highly unsaturated fatty acids (HUFA). A 2:1 (mol/mol) mixture of trieicosapentaenoylglycerol
and tripalmitoylglycerol was most susceptible to the AMVN-initiated oxidation among three types of TAG that contained EPA
and palmitic acid (2:1, mol/mol). Compared with 1,2 (or 2,3)-dieicosapentaenoyl-3(or 1)-palmitoylglycerol (EEP) and 1,3-dieicosapentaenoyl-2-palmitoylglycerol
(EPE), the oxidative rate of EEP was somewhat higher. A similar result was obtained for DHA-containing TAG. The oxidative
rate of TAG that contained EPA and palmitic acid (1:2, mol/mol) showed a positive correlation with the amount of EPA in a
single TAG molecule. Moreover, in the nonaqueous system, the oxidative rate of EPA-containing TAG was affected by unsaturation
and carbon chainlength of constituent fatty acids. In the AAPH-initiated oxidation in the aqueous system, the oxidative rate
of TAG with EPA and palmitic acid was higher with the increased quantity of EPA in a single TAG molecule. Also, constituent
fatty acids modified the oxidative rate of EPA-containing TAG in an aqueous system. The glycerol position of EPA and DHA also
affected the oxidative rate of the TAG. EPA and DHA located at the 1,2 (or 2,3)-position of glycerol were more oxidizable
than those at the 1,3-position during AAPH-initiated oxidation. Thus, 1,2(or2,3)-dipalmitoyl-3(or 1)-eicosapentaenoylglycerol
was oxidized faster than 1,3-dipalmitoyl-2-eicosapentaenoylglycerol. These observations suggest that the oxidative stability
of TAG that contain HUFA could be modulated by the oxidation system and TAG structure. 相似文献
1000.
以石灰石为原料,利用管式气体分散式反应器新工艺制备出了粒径30~70nm的碳酸钙粉体。采用X射线衍射(XRD)、扫描电镜(SEM)、粒度分布仪及红外光谱仪(Fr-IR)等测试手段,对产品的物相、形貌和粒度分布进行了表征。X射线衍射表明产物为六方晶系方解石型碳酸钙并且产品结晶性能良好;扫描电镜及粒度分析表明粒度大小均匀、分散性良好;红外光谱表明改性后硬脂酸钠已吸附在碳酸钙表面,碳酸钙颗粒基本呈单分散状态。管式气体分散式反应器制备纳米碳酸钙粉体的优点是工艺简单,操作容易,原料易得,生产的产品粒径小,粒度分布窄,易于工业化生产。 相似文献