The continuous quest for colouring materials has led to an increase in dyes production and use in recent times. Some of the dyes usually find their way into water sources which consequently leads to decrease in the aesthetic beauty of the water resource as well as its use potential. This study examined the potential of an agricultural waste (Litchi seed powder (LSP)) for the sequestration of a hazardous dye (Congo red (CR)) from aqueous media. The influence of several experimental drivers such as pH, sorption time, sorbent dosage, particle size and change in water chemistry were also examined. An optimum pH of 2 was established for best uptake of CR. The sorption process can be explained both by the Langmuir and Freundlich isotherm models. The pseudo second order kinetic model best describes the kinetics of the sorption. Scanning electron microscopy showed a significant change in the surface morphology of the spent sorbent. The sorption process was exothermic in nature ($\Delta H^0=-0.45\text{kJ}/\text{mol}$) and spontaneous ($-\Delta G^0=11.52-12.25\text{kJ}/\text{mol}$). Results from this study showed that LSP can be used as a potential low-cost sorbent for dyes decontamination from aqueous media.

对着色材料的不断追求导致近来染料生产和使用的增加。一些染料通常进入水源，因此导致水资源的美学美感及其使用潜力的下降。这项研究检查了农业废料（荔枝籽粉（LSP））从水性介质中螯合有害染料（刚果红（CR））的潜力。还考察了几个实验驱动因素的影响，例如pH，吸附时间，吸附剂用量，粒径和水化学变化。为最佳吸收CR，设定了最适pH为2。吸附过程可以用Langmuir和Freundlich等温线模型来解释。拟二级动力学模型最好地描述了吸附动力学。扫描电子显微镜显示用过的吸附剂的表面形态有显着变化。吸附过程本质上是放热的（$\Delta H^0=-0.45\text{千焦}/\text{摩尔}$）和自发（$-\Delta G^0=11.52-12.25\text{千焦}/\text{摩尔}$）。这项研究的结果表明，LSP可以用作潜在的低成本吸附剂，用于从水性介质中去除染料的污染。