排序方式: 共有48条查询结果,搜索用时 15 毫秒
31.
ZnCl_2法污泥含炭吸附剂对模拟烟气中气态汞的吸附 总被引:1,自引:1,他引:0
采用改进的ZnCl2化学活化法制备污泥含炭吸附剂,利用EDS以及氮吸附等多种测试手段对所制得的污泥含炭吸附剂进行表征,并利用其处理模拟烟气汞污染物,实验结果表明,污泥含炭吸附剂对Hg0的吸附包括物理吸附作用和化学吸附作用,以物理吸附作用为主;随着Hg0入口浓度的提高,污泥含炭吸附剂的Hg0饱和吸附容量增大;随着吸附反应温度的升高污泥含炭吸附对Hg0的吸附作用减弱;在吸附反应温度125℃,Hg0入口浓度60.4 ug/m3,污泥含炭吸附剂和选定的活性炭对Hg0的吸附容量分别为81.2 ug/g和53.8 ug/g,污泥含炭吸附剂对Hg0的吸附作用好于选定的活性炭. 相似文献
32.
Dyes are an important class of pollutants, and can even be identified by the human eye. Disposal of dyes in precious water resources must be avoided, however, and for that various treatment technologies are in use. Among various methods adsorption occupies a prominent place in dye removal. The growing demand for efficient and low-cost treatment methods and the importance of adsorption has given rise to low-cost alternative adsorbents (LCAs). This review highlights and provides an overview of these LCAs comprising natural, industrial as well as synthetic materials/wastes and their application for dyes removal. In addition, various other methods used for dye removal from water and wastewater are also complied in brief. From a comprehensive literature review, it was found that some LCAs, in addition to having wide availability, have fast kinetics and appreciable adsorption capacities too. Advantages and disadvantages of adsorbents, favourable conditions for particular adsorbate–adsorbent systems, and adsorption capacities of various low-cost adsorbents and commercial activated carbons as available in the literature are presented. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed. 相似文献
33.
Alberto J. Nieto-Sanchez Mara Olivares-Marin Susana Garcia Covadonga Pevida Eduardo M. Cuerda-Correa 《Chemosphere》2013
In this work, a statistical experimental design is performed in order to prepare CaCO3 materials for use as CaO-based CO2 sorbent precursors. The influence of different operational parameters such as synthesis temperature (ST), stirring rate (SR) and surfactant percent (SP) on CO2 capture is studied by applying Response Surface Methodology (RSM). The samples were characterized using different analytical techniques including X-ray diffraction, N2 adsorption isotherm analysis and Scanning Electron Microscopy–X-ray Energy Dispersive Spectroscopy (SEM-EDX). CO2 capture capacity was determined by means of a thermogravimetric analyzer which recorded the mass uptake of the samples when these were exposed to a gas stream containing diluted (15%) CO2. The statistical approach used in this work provides a rapid way of predicting and optimizing the main preparation variables of CaO-derived sorbents for CO2 sorption. The results obtained clearly indicate that four parameters statistically influence CO2 uptake: SR, the square of SR, its interaction with SP and the square of SP. 相似文献
34.
Removal efficiency of fluoride by novel Mg-Cr-Cl layered double hydroxide by batch process from water 总被引:1,自引:0,他引:1
Sandip Mandal Swagatika Tripathy Tapswani Padhi Manoj Kumar Sahu Raj Kishore Patel 《环境科学学报(英文版)》2013,25(5):993-1000
The fluoride ion removal from aqueous solution using synthesized Mg-Cr-Cl layered double hydroxide has been reported.Mg-Cr-Cl was characterized by X-ray powder diffraction,Fourier-transform infrared,thermo-gravimetric analysis,differential thermal analysis,and scanning electron microscope.Adsorption experiments were carried out in batch mode as a function of adsorption dosages,contact time,pH,and initial fluoride concentration to get optimum adsorption capacity.The adsorption kinetic study showed that the adsorption process followed first order kinetics.The fluoride removal was 88.5% and 77.4% at pH 7 with an adsorbent dose of 0.6 g/100 mL solution and initial fluoride concentration of 10 mg/L and 100 mg/L,respectively.The equilibrium was established at 40 min.Adsorption experiment data were fitted well with Langmuir isotherm with R 2 = 0.9924.Thermodynamic constants were also measured and concluded that the adsorption process was spontaneous and endothermic in nature.The removal percentage decreased slowly with increasing pH.This process is suitable for industrial effluents.The regeneration of the material is not possible. 相似文献
35.
As with other construction materials, coal fly ash contains trace metals that can leach into the natural environment. As part of a broader effort to encourage appropriate coal combustion product use in infrastructure applications (e.g., road construction, stabilization, and structural fill), this study evaluated traditional and low‐cost adsorbent alternatives for their capacity to attenuate trace metals. Batch sorption tests were used as a preliminary screen for a wide variety of low cost (e.g., steel byproducts, rubber dust, and compost) and innovative materials (e.g., kudzu, biofilm, and pond weed) as well as conventional materials (activated carbon, alumina, and zeolites). The removal rates were demonstrated in this study by observing the calculated distribution coefficient (Kd) which were determined using a program called MATLAB. Limestone and steel byproducts were found to be particularly effective with large Kd values of 15,740, 1,520, and 540 L kg?1 for cadmium, chromium, and selenium and, for ladle refractory and mill scale, Kd values of 3,910, 670, and 1,760 L kg?1 were observed. Among the three metals tested for this study, it was observed that most low cost and innovative materials removed cadmium quite efficiently; however, the removal of selenium and chromium depended on the substrate and prevailing pH. In general, these results suggest that alternative materials may have relevance in niche applications where leaching is a concern that can be addressed through enhanced attenuation capacity via blending or layering of adsorbents. 相似文献
36.
大气有机污染物的吸附剂富集—超临界流体萃取—色质联用分析 总被引:12,自引:0,他引:12
本文研究了有机吸附剂GDX-1011,GDX-102,GDX-502富集大气中痕量有机污染物的超临界流全萃取方法,比较了三种吸附剂富集大气中有机物的主要成分其超临界流体的萃取效率,并与索钉抽提法做了对比,结果表明,GDX-502吸附有机物组分最多,超临界流体萃取对GDX-502的解吸效率也最高,对被GDX-502吸附的可以定量分析的35种有机物的平均回收率为84.5-108.9%,相对标准偏差为1 相似文献
37.
本文报道了粘土吸附剂自溶液中吸附铅的吸附性能及热力学性能.该吸附剂吸附铅的最佳处理条件为:用3MH2SO4振荡处理4h,然后在200℃下培烧2h,该吸附为放热过程.饱和吸附量为16.8mg/g,符合Langmuir吸附等温线,其吸附热为-609.6J/mol. 相似文献
38.
本文系统研究了菌丝体 -甲壳素 (甲壳素 )作为水处理剂对去除水体中Ni2 + 离子时的吸附特性 ,结果表明 ,甲壳素作为水处理剂 ,在较大pH值变化范围内 ,对Ni2 + 离子与柠檬酸镍都有较高的吸附容量 ;甲壳素在吸附金属离子的同时 ,对H+ 有吸附作用 ,且H+ 是金属离子的竞争性抑制剂。将甲壳素与市售吸附树脂相比 ,其对阳离子 (Ni2 + )和络阴离子(柠檬酸镍Ni(cit) 2 -)的吸附特性类似于阳离子交换树脂。同时 ,甲壳素不会带来二次污染 ,是一种具有广泛应用前景的环保型工业水处理剂。 相似文献
39.
采用改进的ZnCl2学活化法制备污泥含炭吸附剂,利用EDS以及氮吸附等多种测试手段对所制得的污泥含炭吸附剂进行表征,并利用其处理模拟烟气汞污染物,实验结果表明,污泥含炭吸附剂对Hg^0吸附包括物理吸附作用和化学吸附作用,以物理吸附作用为主;随着Hg^0入口浓度的提高,污泥含炭吸附剂的Hg^0饱和吸附容量增大;随着吸附反应温度的升高污泥含炭吸附对Hg^0的吸附作用减弱;在吸附反应温度125℃,Hg^0入口浓度60.4μg/m3污泥含炭吸附剂和选定的活性炭对Hg^0吸附容量分别为81.2gg/g和53.8μg/g,污泥含炭吸附剂对Hg^0吸附作用好于选定的活性炭。 相似文献
40.