共查询到20条相似文献,搜索用时 109 毫秒
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粉煤灰是电厂的典型废弃物,且具有一定的吸附能力,可作为一种较为经济的吸附剂供人们使用。为提高和改善其吸附性能,采用酸改性方法和微波联合酸碱改性方法制备了两种改性粉煤灰,对比原粉煤灰,探究了两种改性粉煤灰对于甲苯的吸附性能,并通过SEM和BET对粉煤灰改性前后进行表征。结果表明:酸改性粉煤灰吸附甲苯达到吸附饱和时间为380 min,最大甲苯吸附量为39 mg/g,微波联合酸碱改性粉煤灰性能最好,反应达到吸附饱和时间为470 min左右,对甲苯的最大吸附量达到48 mg/g。 相似文献
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改性粉煤灰对苯酚的吸附特性研究 总被引:2,自引:0,他引:2
研究了苯酚在改性粉煤灰上的吸附特性。结果表明,改性粉煤灰吸附苯酚速率快,在低pH值下吸附效果更好,等温吸附过程符合Freundlich模型,其吸附等温线为q=1.7081C^0.9248。 相似文献
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粉煤灰对甲基橙的吸附研究 总被引:12,自引:0,他引:12
研究了粉煤灰对甲基橙的吸附性能,探讨了各种处理条件对吸附效果的影响。结果表明:对于80mL初始浓度为6.4mg·L-1的甲基橙模拟废水,采用10g·L-1粉煤灰对其进行吸附处理,当pH=3~5时,于20℃下恒温振荡1.5h,其去除率可达99.5%。 相似文献
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Modifications of commercial activated carbons by chemical treatment with HNO3 or HCl and HF and the adsorption behavior of simple aromatic compounds (aniline, pyridine, phenol, and benzene) on activated carbon and modified activated carbon were investigated. The results show that the textural properties change a little after these modifications, but the surface acidity (mainly oxygen‐containing groups) of activated carbon modified with HNO3 increases greatly. The effect of ash of activated carbon on adsorption of the organic compounds mentioned above is insignificant. However, addition of surface acidity (mainly surface oxygen‐containing groups) decreases the adsorption capacity of compounds significantly. The adsorption uptake of compounds on activated carbon with oxidation of HNO3 is low possibly due to dispersive interaction, water cluster blocking, or competition between water and compounds adsorbed on activated carbon's surface because of hydrophilic increase of the activated carbon surface. The solubility of aromatic compounds in water has an important effect on the adsorption capacity of activated carbon. qm and KL (Langmuir adsorption parameters) for the aromatic compounds vary similarly. 相似文献
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新生MnO2对茜素红吸附脱色的研究 总被引:2,自引:0,他引:2
以新生MnO2为吸附剂,对水中茜素红染料进行了脱色研究,探讨了影响吸附的因素。结果表明,降低pH值、增加吸附剂投加量,有利于新生水合二氧化锰对茜素红染料的脱色。当新生态水合MnO2浓度为300 mg/L,茜素红浓度为400 mg/L,pH=2,反应时间为60 min时,茜素红脱色率达90%以上。实验还发现对茜素红染料吸附较好符合Freundich吸附等温式,吸附速率较快。 相似文献
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S. Bouzid A. Khenifi K. A. Bennabou R. Trujillano M. A. Vicente 《Chemical Engineering Communications》2013,200(4):520-533
An Algerian montmorillonite was modified with two organic surfactants, methyltriphenyl phosphonium bromide and n-hexyltriphenyl phosphonium bromide. The solids obtained were used as adsorbents to remove Orange II, an anionic dye from aqueous solutions. Batch experiments were conducted to study the effects of temperature (20–60°C), initial concentration of adsorbate (50–150 mg L?1) and pH of solution 6.5 on dye adsorption. Due to their organophilic nature, exchanged montmorillonites were able to adsorb Orange II at a very high level. Adsorption of Orange II for B-NHTPB and B-MTPB at different pH show that the adsorption capacity clearly decreases with an increase in pH of the initial solution from 2 to 8, this decrease being dramatic for pH > 8. This may be due to hydrophobic interactions of the organic dye with both phosphonium molecules and the remaining non-covered portion of siloxane surface. The kinetics of the adsorption was discussed on the basis of three kinetic models, i.e., the pseudo-first-order, the pseudo-second-order, and the intraparticle diffusion models. Equilibrium is reached after 30 min and 60 min for B-MTPB and B-NHTPB, respectively; the pseudo-second-order kinetic model described very well the adsorption of Orange II on modified bentonites. The non-linear Langmuir model provided the best correlation of experimental data, maximum adsorption of Orange II is 53.78 mg g?1 for B-NHTPB and 33.79 mg g?1 for B-MTPB. The thermodynamic parameters, such as free energy of adsorption (ΔG°), enthalpy change (ΔH°), and entropy change (ΔS°) were also determined and evaluated. From thermodynamic studies, it was deduced that the adsorption was spontaneous and exothermic. 相似文献