Due to the increasing concern about the environmental pollution problems, it is so important to perform a number of methods for removing hazardous heavy metals from industrial liquid wastes. Adsorption technique is the most effective and economical one. In the present study, two agricultural by-products namely; cottonseed and soybean hulls, resulting from the oil industry, have been used in the adsorption of thorium element from a wastewater effluent coming from different industries. The results obtained indicate that maximum removal of thorium from a prepared solution takes place at pH 5 where equilibrium was attained after 100 min; using an adsorbent dose of 3 and 3.5 g/L for cottonseed and soybean hulls, respectively. On the other hand, the obtained mathematical data together with the obtained adsorption kinetic parameters indicate that both of cottonseed and soybean hulls could be useful adsorbents for thorium removal from industrial liquid wastes, especially when the low cost, environmental issues and high availability of these materials are considered.

中文翻译：

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农副产品对重金属污染工业废水的处理

由于对环境污染问题的日益关注，执行多种方法从工业废液中去除有害重金属非常重要。吸附技术是最有效和最经济的一种。在本研究中，两种农业副产品是；来自石油工业的棉籽和大豆皮已被用于吸附来自不同行业的废水中的钍元素。获得的结果表明，从制备溶液中最大程度地去除钍发生在 pH 值为 5 时，100 分钟后达到平衡；对棉籽和大豆皮分别使用 3 和 3.5 g/L 的吸附剂剂量。另一方面，