LAQV/REQUIMTE, Departamento de Ciências e Tecnologia da Biomassa (DCTB), Faculdade de Ciências e Tecnologia (FCT), Universidade Nova de Lisboa (UNL), 2829-516 Caparica, Portugal.
DICEA, Dipartimento di Ingegneria Civile, Edile e Ambientale; Università di Padova, Padova, Italy.
J Hazard Mater. 2021 Jun 15;412:125201. doi: 10.1016/j.jhazmat.2021.125201. Epub 2021 Jan 22.
Pyrolysis chars derived from rice wastes were chemically activated and used in W(VI) oxyanion adsorption assays in synthetic and mining wastewaters. For comparison purposes, a commercial activated carbon (CAC) was also used. Different experimental conditions were tested in the adsorption assays: solid/liquid ratio (S/L), initial pH, contact time, and initial W concentration. The porous carbon P2C+KOH presented the overall best performance in both media, due to its high surface area (2610 m g), mesopore volume (1.14 cm g), and neutral pH (6.92). In the synthetic wastewater, the highest uptake capacity of P2C+KOH (854 mg g) was found in the assays with an S/L 0.1 g L, an initial pH 2, and an initial W concentration of 150 mg L, for 24 h. This value was almost 8 times higher than the one obtained for CAC (113 mg g). In the mining wastewater, P2C+KOH showed an even higher uptake capacity (1561 mg g) in the assay with the same experimental conditions, which was almost 3 times higher than for CAC (561 mg g). These results suggest that P2C+KOH seems to be an efficient alternative to CAC in the W(VI) adsorption from liquid effluents.
以稻壳废弃物为原料制备的热解炭经化学活化后用于模拟和矿山废水中的 W(VI)阴离子吸附实验。为了进行比较，还使用了商业活性炭（CAC）。在吸附实验中测试了不同的实验条件：固液比（S/L）、初始 pH 值、接触时间和初始 W 浓度。多孔炭 P2C+KOH 在两种介质中均表现出最佳性能，这归因于其高比表面积（2610 m g）、中孔体积（1.14 cm g）和中性 pH 值（6.92）。在合成废水中，在 S/L 为 0.1 g L、初始 pH 值为 2 和初始 W 浓度为 150 mg L、接触时间为 24 h 的条件下，P2C+KOH 的最大吸附容量（854 mg g）最高，而 CAC 的最大吸附容量仅为 113 mg g。在矿山废水中，在相同的实验条件下，P2C+KOH 的吸附容量甚至更高（1561 mg g），是 CAC 的近 3 倍（561 mg g）。这些结果表明，P2C+KOH 似乎是从液体废水中吸附 W(VI)的 CAC 的有效替代品。
