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121.
木质素基树脂的制备及其对重金属离子的吸附性能 总被引:3,自引:0,他引:3
以木质素磺酸钠为原料,利用反相悬浮聚合技术,成功制备木质素基树脂.研究了木质素基树脂的制备工艺及其对重金属离子Pb2+、Cd2+的吸附性能.结果表明,优化的聚合条件为:液体石蜡与反应水溶液的相比为3:1、分散剂占有机相百分含量为2%、温度为90℃、盐酸浓度为3mol/L、甲醛占木质素磺酸钠百分含量为9%、聚合时间为2h.30℃时,所制备的树脂对Pb2+、Cd2+的饱和吸附量分别达到33.6523mg/g和30.12mg/g.所制备的木质素基树脂有大量羟基和磺酸基等含氧基团存在,非常有利于它对重金属离子的吸附.木质素基树脂的比表面积为0.0963m2/g,孔容为0.002389cm3/g,平均孔径为99.2208nm,表明该树脂具有大孔树脂的结构特点. 相似文献
122.
《分离科学与技术》2012,47(9):1349-1355
A new silica gel material covalently bonded with 1-(pyridin-2-yl) imine (SiNPn) was synthesized and well characterized by elemental analysis, FT–IR, 13C NMR of the solid state, nitrogen adsorption-desorption isotherm, BET surface area, B.J.H. Pore sizes, thermogravimetry curves (TGA), and scanning electron microscope (SEM). The new chelating surface exhibits good chemical and thermal stability. The adsorption capabilities of this new system towards toxic metal ions (Hg2+, Cd2+, Pb2+, and Zn2+) were investigated using the batch method. The percentage limits of extraction were determined by atomic absorption measurements. 相似文献
123.
JIANG Tao SU Yuanfu Chemical Engineering Research Center East China University of Chemical Technology Shanghai China 《金属学报(英文版)》1991,4(7):1-7
Studies have been made on the extraction of Zn and Cd by TBP(tri-n-butyl phosphate)from diluent hydrochloric acid solutions of soldium chloride.The experiments show that thespecies extracted from diluent HCI solutions of NaCl appear to be predominantly ZnCl_2·2TBP and CdCl_2·2TBP.For Cd,at lower acidities,anionic complexes of the typeH_2CdCl_3 are also extracted.As the acidity is increased,H_2CdCl_4 appear to be predominantcomplexes in organic phase.For Zn,the acidocomplexes of the type HZnCl_3 appear in organ-ic phase after the acidity of solutions reaching a certain value([HCl]>0.1 mol/L).Furthermore,the ultraviolet absorption spectra of both aqueous and organic phases have beenstudied,and the infrared spectra of the organic phases have been exomined.The extractionmechanism and temperature effect are also discussed. 相似文献
124.
《中国有色金属学会会刊》2022,32(10):3404-3419
Mixed bacteria were enriched from heavy metals mine soil for cadmium (Cd(II))-containing wastewater treatment. Batch adsorption experiment results showed that the optimal pH, temperature, initial Cd(II) concentration, and biomass dosage were 6.0, 30 °C, 20 mg/L, and 1 g/L, respectively. Living biomass exhibited better Cd(II) removal efficiency (91.97%) than autoclaved biomass (79.54%) under optimal conditions. The isotherms and kinetics of living biomass conformed to the Langmuir isotherm model and pseudo-first-order kinetic model, respectively. FTIR results implied that amine groups, hydroxyl groups and phosphoric acid play an important role in the Cd(II) adsorption process, while XRD results showed that crystalline Cd(OH)2 and CdO were obtained. After Cd(II)-containing wastewater treatment exposure, the dominant bacteria genera included Comamonas (39.94%), unclassified_f__Enterobacteriaceae (34.96%), Ochrobactrum (14.07%), Alcaligenes (4.84%), Bordetella (2.07%), Serratia (1.04%), and Bacillus (1.01%). Function prediction showed that the abundance of metabolic genes changed significantly. This study proposes the potential application of mixed bacteria for Cd(II)-containing wastewater treatment. 相似文献
125.
室温下测量了本实验室生长的Cd0.8Mn0.2Te和Cd0.9Mn0.1Te单晶体的法拉第旋转谱.通过提高布里渊区中心L点的能隙值(E1)改进了法拉第旋转的多振子模型.用改进的模型拟合实验结果,得到Cd0.8Mn0.2Te和Cd0.9Mn0.1Te单晶体布里渊区中心F点的能隙值(E0)分别为1.804 eV和1.667 eV.该E0值比以往任何研究都更接近于计算值. 相似文献
126.
127.
Composite fluorocarbon/ZnO films were deposited by RF sputtering, using polytetrafluoroethylene and Zn targets, on polyethylene terephthalate substrates. Argon and oxygen were used as working and reacting gases, respectively, with an oxygen:argon volume ratio of 3:1. The films were characterized by X-ray Photoelectron Spectroscopy, Fourier Transform Infrared Spectroscopy and static contact angle measurements. It was found that the deposited films are made up of the four components -CF3, -CF2-, -CF- and -C-. The proportions of the four components varied with sputtering conditions. There was a large number of C=C double bonds on the surface of deposited films. The static contact angle of the deposited films was greater than 90°, indicating excellent hydrophobicity. The contact angle of films decreased after washing, and the washing fastness of the composite films were slightly inferior to those of the fluorocarbon films. 相似文献
128.
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130.
Y. C. Sharma G. Prasad D. I. Rupainwar 《The International journal of environmental studies》2013,70(4):315-320
The adsorption of Cd(II) onto wollastonite has been reported. Adsorption increased from 55.7 to 93.6% by decreasing the concentration of Cd(II) from 2.0 x 10‐4M to 0.5 x 10‐4M. The rearranged Lagergren equation has been used for dynamic modelling of the process. However, the value of rate constant at 30°C was found to be 3.17 x 10‐2min‐1. Equilibrium modelling was carried out using the Freundlich isotherm equation and constants have been calculated. Thermodynamic studies were carried out and values of standard free energy (?G°), enthalpy (?H°) and entropy (AS°) were calculated at various temperatures. Low temperatures favour the uptake of Cd(II) in the process. 相似文献