This study measures and evaluates the capabilities of desiccated coconut waste, a waste by-product produced from coconut milk processing, as an adsorbent precursor for the removal of azo dyes in wastewater. The results show that the desiccated coconut waste performed the highest adsorption capacity towards the Congo Red dye in pH 2 condition where the Q_max = 0.071 mmol/g. The adsorption capacity of the coconut waste-based adsorbent is relatively high in azo dye removal among the tested waste precursors such as coir pith, tamarind fruit shells, hazelnut shells, and banana peel. The analysis of azo dye adsorption equilibrium and kinetics using appropriate isotherm and kinetic model shows excellent fitting with Langmuir isotherm and pseudo-second-order kinetic model, where the determination coefficient, R² ≈ 1, indicates a monolayer chemical adsorption process, with a maximum monolayer capacity of 0.004 mmol/g. These findings support that coconut waste-based adsorbent is highly potential for application of Congo Red removal in wastewater.

本研究测量并评估了干燥椰子废料（一种从椰奶加工中产生的废副产品）作为去除废水中偶氮染料的吸附剂前体的能力。结果表明，干燥的椰子废料在 pH 2 条件下对刚果红染料的吸附能力最高，其中Q _max = 0.071 毫摩尔/克。在椰壳髓、罗望子果壳、榛子壳和香蕉皮等被测废物前体中，椰子废料基吸附剂在去除偶氮染料方面的吸附能力较高。使用适当的等温线和动力学模型对偶氮染料吸附平衡和动力学的分析表明与朗缪尔等温线和准二级动力学模型非常吻合，其中决定系数R ² ≈ 1 表明单层化学吸附过程，最大单层容量为 0.004 mmol/g。这些发现支持基于椰子废料的吸附剂在去除废水中的刚果红方面具有很高的潜力。