School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, 28 Xianning West Road, Xi'an, Shaanxi, 710049, PR China.
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 710055, Xi'an, PR China.
Environ Pollut. 2022 Dec 1;314:120236. doi: 10.1016/j.envpol.2022.120236. Epub 2022 Sep 29.
Arsenic (As) is among the most dangerous metalloids and is harmful to human wellbeing. In this laboratory study, Al(III)-modified kapok fibres (Al-Kapok) were used to remove As(V) from water. The sorbent was characterised using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Batch experiments were performed to observe the performance of Al-Kapok in the removal of As(V) and to examine the effects of pH, temperature, adsorbent dose, and coexisting ions on the adsorption process. The surface of the sorbent changed after aluminium modification, and the results of the batch experiments showed that the adsorption of As(V) occurred mainly via endothermic-spontaneous chemisorption at the solution and solid interface of Al-Kapok. The As(V) removal efficiency was approximately 76%-84%, and it was slightly affected at pH levels below 8.0. Further study showed that the maximum adsorption capacity of Al-Kapok for As(V) was 118 μg/g at 30 °C and pH 6, and notable adverse effects were caused by the presence of SOand PO. It was also found that the boundary layer and film diffusion contributed more to As(V) adsorption. After five adsorption/desorption cycles, regeneration recovered approximately 92% of the adsorption capacity of Al-Kapok used. Overall, Al-Kapok appears to be a suitable adsorbent material for the purification of As-contaminated water.
砷（As）是最危险的类金属元素之一，对人类健康有害。在这项实验室研究中，使用三价铝改性木棉纤维（Al-Kapok）去除水中的砷（V）。使用傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）结合能量色散 X 射线光谱（EDX）对吸附剂进行了表征。进行了批量实验以观察 Al-Kapok 在去除 As(V)方面的性能，并研究 pH、温度、吸附剂剂量和共存离子对吸附过程的影响。铝改性后，吸附剂的表面发生了变化，批量实验结果表明，As(V)的吸附主要通过界面的吸热自发化学吸附发生。As(V)的去除效率约为 76%-84%，在 pH 值低于 8.0 时略有影响。进一步的研究表明，Al-Kapok 对 As(V)的最大吸附容量为 118μg/g，温度为 30°C，pH 值为 6，SO和 PO 的存在会产生明显的不利影响。还发现边界层和膜扩散对 As(V)的吸附贡献更大。经过五次吸附/解吸循环后，再生恢复了 Al-Kapok 吸附容量的约 92%。总体而言，Al-Kapok 似乎是一种适合用于净化含砷污染水的吸附材料。
