Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China.
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; IRSM-CAS/HK PolyU Joint Laboratory on Solid Waste Science, Hung Hom, Kowloon, Hong Kong, China.
J Environ Manage. 2021 Jun 15;288:112382. doi: 10.1016/j.jenvman.2021.112382. Epub 2021 Mar 21.
With rapid economic growth and urbanisation, the reuse and recycling of solid wastes has become a high priority for the sustainable development of modern cities. In this study, two typical solid wastes, incinerated sewage sludge ash (ISSA) and waste bentonite, were co-valorised to produce granular adsorbents through a simple and energy-saving pelletisation/sintering process. A mixture of ISSA and bentonite at a weight ratio of 3:1 was pelletised and sintered at 700 °C. The resultant ceramsite, with good mechanical strength, could effectively remove Pb(Ⅱ) from aqueous solutions. The adsorption kinetics can be described by the pseudo-first-order (PFO) model. The results indicated that the Pb(Ⅱ) adsorption process was dominated by electrostatic attraction, precipitation, and complexation. The isothermal data exhibited a good correlation with the Freundlich model, indicating that the adsorption process was non-ideal and spontaneous. The maximum adsorption capacity was approximately 21.6 ± 0.35 mg/g at 318 K. After 5 cycles of regeneration, the adsorbent maintained good adsorption performance. Moreover, the removal rate was not greatly affected by ionic strength. These findings demonstrate that the granular adsorbent prepared with ISSA and waste bentonite can be recognised as a promising adsorbent for Pb-containing wastewater treatment.
随着经济的快速增长和城市化进程的推进，固体废弃物的再利用和回收已成为现代城市可持续发展的当务之急。在这项研究中，我们通过简单节能的制粒/烧结工艺将两种典型的固体废弃物——焚烧污水厂污泥灰（ISSA）和废膨润土共矿化，制备出颗粒状吸附剂。将 ISSA 和膨润土以 3:1 的重量比混合，在 700°C 下进行制粒和烧结，得到的陶粒具有良好的机械强度，可有效去除水溶液中的 Pb(Ⅱ)。吸附动力学可用准一级（PFO）模型描述。结果表明，Pb(Ⅱ)的吸附过程主要受静电吸引、沉淀和络合作用的控制。等温数据与 Freundlich 模型拟合良好，表明吸附过程是非理想和自发的。在 318 K 时，最大吸附容量约为 21.6±0.35mg/g。经过 5 次再生循环后，吸附剂仍保持良好的吸附性能。此外，去除率受离子强度的影响不大。这些发现表明，用 ISSA 和废膨润土制备的颗粒状吸附剂可作为一种有前途的含 Pb 废水处理吸附剂。
