Heavy metals released by various industries are among the major pollutants found in water resources. In this research, biosorption technique was employed to remove cadmium (Cd²⁺) from an aqueous system using a novel biosorbent developed from okara waste (OW), a residue from soya bean–based food and beverage processing. Characterisation results revealed that the OW biosorbent contained functional groups such as hydroxyl-, carboxyl- and sulphur-based functional groups, and the surface of the biosorbent was rough with multiple fissures which might be the binding sites for the pollutant. The effects of dosage, solution pH, initial Cd²⁺ concentration, temperature and contact time were investigated using batch adsorption mode. The biosorption equilibrium and kinetic were best described by the Langmuir and Elovich models, respectively. The maximum biosorption capacities predicted by the Langmuir model were 10.91–14.80 mg/g at 30–70 °C, and the biosorption process was favourable as evident from 0 < R_L < 1. The uptake of Cd²⁺ by the OW biosorbent was spontaneous and endothermic. The plausible biosorption mechanisms of this study could be ionic exchange, hydrogen bonding and electrostatic interactions. The Cd²⁺ loaded OW biosorbent could be regenerated using 0.4 M of HCl solution and regeneration was studied for 4 adsorption-desorption cycles. The present investigation supported that OW can be reused as a value-added biosorbent product for the removal of Cd²⁺ from the contaminated water.

各行业排放的重金属是水资源中的主要污染物之一。在这项研究中，采用生物吸附技术从含水系统中去除镉 (Cd ²⁺ )，使用一种新型生物吸附剂，这种生物吸附剂是从豆渣废物 (OW) 中开发的，这是一种基于大豆的食品和饮料加工的残留物。表征结果表明, OW 生物吸附剂含有羟基、羧基和硫基等官能团, 生物吸附剂表面粗糙, 有多个裂缝, 可能是污染物的结合位点。用量、溶液 pH 值、初始 Cd ^{2+ 的影响}使用分批吸附模式研究浓度、温度和接触时间。生物吸附平衡和动力学分别由 Langmuir 和 Elovich 模型最好地描述。Langmuir 模型预测的最大生物吸附容量在 30-70 °C 下为 10.91-14.80 mg/g，并且从 0 < R _L < 1可以看出生物吸附过程是有利的。OW 生物吸附剂对 Cd ²⁺的吸收为自发和吸热。本研究可能的生物吸附机制可能是离子交换、氢键和静电相互作用。镉²⁺负载的 OW 生物吸附剂可以使用 0.4 M HCl 溶液进行再生，并研究了 4 个吸附-解吸循环的再生。目前的调查支持 OW 可以作为一种高附加值的生物吸附剂产品重新使用，用于从受污染的水中去除 Cd ²⁺。