Mishra P C, Patel R K
Department of Chemistry, PIET, Mandiakudar, Rourkela , Orissa, India.
J Hazard Mater. 2009 Aug 30;168(1):319-25. doi: 10.1016/j.jhazmat.2009.02.026. Epub 2009 Feb 20.
In this study, activated carbon, kaolin, bentonite, blast furnace slag and fly ash were used as adsorbent with a particle size between 100 mesh and 200 mesh to remove the lead and zinc ions from water. The concentration of the solutions prepared was in the range of 50-100 mg/L for lead and zinc for single and binary systems which are diluted as required for batch experiments. The effect of contact time, pH and adsorbent dosage on removal of lead and zinc by adsorption was investigated. The equilibrium time was found to be 30 min for activated carbon and 3h for kaolin, bentonite, blast furnace slag and fly ash. The most effective pH value for lead and zinc removal was 6 for activated carbon. pH value did not effect lead and zinc removal significantly for other adsorbents. Adsorbent doses were varied from 5 g/L to 20 g/L for both lead and zinc solutions. An increase in adsorbent doses increases the percent removal of lead and zinc. A series of isotherm studies was undertaken and the data evaluated for compliance was found to match with the Langmuir and Freundlich isotherm models. To investigate the adsorption mechanism, the kinetic models were tested, and it follows second order kinetics. Kinetic studies reveals that blast furnace slag was not effective for lead and zinc removal. The bentonite and fly ash were effective for lead and zinc removal.
在本研究中，使用粒度在100目至200目之间的活性炭、高岭土、膨润土、高炉矿渣和粉煤灰作为吸附剂，以去除水中的铅和锌离子。对于单体系和二元体系，所制备溶液中铅和锌的浓度范围为50 - 100 mg/L，并根据批量实验的要求进行稀释。研究了接触时间、pH值和吸附剂用量对铅和锌吸附去除效果的影响。发现活性炭的平衡时间为30分钟，高岭土、膨润土、高炉矿渣和粉煤灰的平衡时间为3小时。活性炭去除铅和锌的最有效pH值为6。对于其他吸附剂，pH值对铅和锌的去除没有显著影响。铅和锌溶液的吸附剂用量均在5 g/L至20 g/L之间变化。吸附剂用量的增加会提高铅和锌的去除率。进行了一系列等温线研究，发现评估的数据符合朗缪尔等温线模型和弗伦德里希等温线模型。为了研究吸附机理，对动力学模型进行了测试，结果表明其符合二级动力学。动力学研究表明，高炉矿渣对铅和锌的去除效果不佳。膨润土和粉煤灰对铅和锌的去除效果良好。
