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1.
Shu-Yii Wu Yong-Fang Liu Ya-Chieh Li Chun-Min Liu 《International Journal of Green Energy》2015,12(10):1025-1030
The CO2 absorption capacities of potassium glycinate, potassium sarcosinate (choline, proline), mono-ethanolamine (MEA), and tri-ethanolamine were evaluated to find the optimal absorbent for separating CO2 from gaseous products by a CO2 purification process. The absorption loading, desorption efficiency, cost, and environmental tolerance were assessed to select the optimal absorbent. MEA was found to be the optimum absorbent for separating the CO2 and H2 mixture in gaseous product. The maximum absorption loading rate was 0.77 mol CO2 per mol MEA at temperature of 20°C and absorbent concentration of 2.5 mol/L, whereas desorption efficiency was 90% by heating for 3 h at 130°C. MEA was found to be an optimal absorbent for the purification process of CO2 during gaseous production. 相似文献
2.
Carbon coated monolith was prepared by sucrose solution 65 wt.% via dip-coating method. Sulfonation of incomplete carbonized carbon coated monolith was carried out in order to synthesize solid acid catalyst. The textural structure characteristics of the solid acid catalyst demonstrated a low surface area and pore volume. Palm fatty acid distillate (PFAD), a by-product of palm oil refineries, was utilized as oil source in biodiesel production. The esterification reaction subjected to different reaction conditions was performed by using the sulfonated carbon coated monolith as heterogeneous catalyst. The sulfonation process had been performed by using vapour of concentrated H2SO4 that was much easier and efficient than liquid phase sulfonation. Total acidity value of carbon coated monolith was measured for unsulfonated sample (0.5 mmol/g) and sulfonated sample (4.2 mmol/g). The effect of methanol/oil ratio, catalyst amount and reaction time were examined. The maximum methyl ester content was 89% at the optimum condition, i.e. methanol/oil molar ratio (15:1), catalyst amount (2.5 wt.% with respect to PFAD), reaction time (240 min) and temperature 80 °C. The sugar catalyst supported on the honeycomb monolith showed comparable reactivity compared with the sugar catalyst powder. However, the catalyst reusability studies showed decrease in FFA% conversion from 95.3% to 68.8% after four cycles as well as the total acidity of catalyst dropped from the value 4.2 to 3.1 mmol/g during these cycles. This might be likely due to the leaching out of SO3H group from the sulfonated carbon coated monolith surface. The leaching of active species reached a plateau state after fourth cycle. 相似文献
3.
此文提出了内螺纹变截面铜管分段拉仲一次成形新工艺,并就工艺因素对该管拉伸成形的影响进行了试验研究,从而为合理制订成形工艺提供了依据。 相似文献
4.
Photoactive aluminum doped ZnO(AlZnO) was synthesized by sol-gel method.After that,AlZnO photocatalyst was deposited on five carbon-based materials(CBMs) using ultrasonic route followed by solid-state mixing using ball mill.The CBMs used were poly aniline(PANI),carbon nitride(CN),carbon nanotubes(CNT),graphene(G),and carbon nanofibers(CNF).The crystal phases,elemental compositions,morphological,and optical properties of the AlZnO@CBMs composites were investigated.Experimental results revealed that two of AlZnO@CBMs composites exhibited superior bleaching efficiency(100% removal) and photocatalytic stability(three cycles) for 50 μmol/L Methylene Blue(MB) contaminated water after 60 min irradiation in visible light at pH 6.5,0.7% H_2O_2,and 5 g/L inorganic salts.Under optimum conditions,AlZnO@CBMs nanocomposites were employed for the treatment of mixed dyestuffs composed of MB,Methyl Orange(MO),Astrazone Blue FRR(BB 69),and Rhodamine B(RhB) dyes under dark,ultraviolet,visible,and direct sunlight.For mixed dyestuffs,the AlZnO@G achieved the highest dye sorption capacity(60.91 μmol dye stuffs/g) with kinetic rate 8.22 × 10~(-3) min~(-1) in 90 min via multi-layer physisorption(Freundlich isotherm) on graphene sheet.In additions,AlZnO@CN offered the highest photo-kinetic rate(K_(photo)) of~54.1 × 10~(-3) min~(-1)(93.8% after 60 min) under direct sunlight.Furthermore,the selective radical trapping experiment confirmed that the holes and oxidative superoxide radicals are crucial on dyes photodegradation pathway.Owing to their superior performance,AlZnO@G and AlZnO@CN nanocomposites can offer an effective in-situ solar-assisted adsorption/photocatalytic remediation of textile wastewater effluents. 相似文献
5.
尝试了使用5%钼酸铵-5%磷酸二氢铵溶液组成石墨管连续涂覆结合基体改进剂的方法,应用于地表水Pb的测量中。实验表明,本法具有提高石墨管在使用过程中的稳定性,消除基体效应的作用。 相似文献
6.
本文通过对影响街道空气中一氧化碳污染的因素进行了大量的监测及综合分析,找出乌鲁木齐市主要街道空气中一氧化碳的污染规律,为控制我市汽车污染提供科学依据. 相似文献
7.
8.
城市高架道路建设对机动车尾气污染的影响分析 总被引:3,自引:0,他引:3
通过现场观测和对比,分析了城市一般道路上和城市高架道路下机动车排放污染物浓度差异的原因,分析结果表明,扩散条件对城市机动车尾气污染有着重要影响,例举日本对城市高架道路建设的有关规定,提出应重视城市高架道路建设的环境预评估等。 相似文献
9.
开口圆管非对称弯曲时,在尺寸、形状均有较高精度要求的情况下弯曲有一定的难度。此文介绍了一种成功的开口圆管非对称弯曲冷态成形方法。 相似文献
10.
煤烟型大气污染解决方法 总被引:3,自引:0,他引:3
重点介绍了新型燃煤工艺——水平火焰无烟工业炉及其特点,并提出排烟尾气处理的资源化方案。 相似文献