Schiewer Silke, Patil Santosh B
Department of Civil and Environmental Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
Bioresour Technol. 2008 Apr;99(6):1896-903. doi: 10.1016/j.biortech.2007.03.060. Epub 2007 May 30.
Biosorption can be used as a cost effective and efficient technique for the removal of toxic heavy metals from wastewater. Waste materials from industries such as food processing and agriculture may act as biosorbents. This study investigates the removal of cadmium by fruit wastes (derived from several citrus fruits, apples and grapes). Citrus peels were identified as the most promising biosorbent due to high metal uptake in conjunction with physical stability. Uptake was rapid with equilibrium reached after 30-80 min depending on the particle size (0.18-0.9 mm). Sorption kinetics followed a second-order model. Sorption equilibrium isotherms could be described by the Langmuir model in some cases, whereas in others an S-shaped isotherm was observed, that did not follow the Langmuir isotherm model. The metal uptake increased with pH, with uptake capacities ranging between 0.5 and 0.9 meq/g of dry peel. Due to their low cost, good uptake capacity, and rapid kinetics, citrus peels are a promising biosorbent material warranting further study.
生物吸附可作为一种经济高效的技术，用于去除废水中的有毒重金属。食品加工和农业等行业产生的废料可作为生物吸附剂。本研究调查了水果废料（源自多种柑橘类水果、苹果和葡萄）对镉的去除效果。由于柑橘皮具有高金属吸附量以及物理稳定性，因此被确定为最具潜力的生物吸附剂。根据粒径（0.18 - 0.9毫米）不同，吸附过程迅速，30 - 80分钟后达到平衡。吸附动力学符合二级模型。在某些情况下，吸附平衡等温线可用朗缪尔模型描述，而在其他情况下，则观察到呈S形的等温线，不符合朗缪尔等温线模型。金属吸附量随pH值升高而增加，干皮的吸附容量在0.5至0.9毫克当量/克之间。由于成本低、吸附容量高且动力学迅速，柑橘皮是一种有前景的生物吸附剂材料，值得进一步研究。
