In the current study tea waste and rice husk biochars were used for the elimination of Cr(VI) from wastewater with the objectives to study the effect of pH (3–10), shaking time (0.016–24 h), sorbent dose (0.1–1.3 g L⁻¹) and initial concentration of Cr(VI) (10–250 mg L⁻¹). The Cr(VI) sorption was studied under various factors in which solution pH played a main role and at pH 5.2, maximum 99.3% and 96.8% Cr(VI) were removed by tea waste biochar (TWB) and rice husk biochar (RHB), respectively. In comparison, 197.5 mg g⁻¹ and 195.24 mg g⁻¹ Cr(VI) were sorbed by TWB and RHB, respectively with 120 mg L⁻¹ initial Cr(VI) concentration. In contact time study, after 2 h, equilibrium was achieved for both biochars which indicated that the Cr(VI) elimination from aqueous medium is a fast process. Kinetic and isotherm modeling data showed that pseudo-second order model and Langmuir (monolayer sorption) models provided the best fit for sorption of Cr(VI) onto both biochars. The –OH, COO– and –NH₂ functional groups were involved in the sorption of Cr(VI) onto biochars according to FTIR. Biochars produced from both biomass effectively removed Cr(VI) from polluted water, however in comparison sorption capacity of TWB was slightly higher than RHB. It was concluded that TWB and RHB could provide a cost-effective and viable option for elimination of Cr(VI) from wastewater.

在本研究中，茶废料和稻壳生物炭被用于消除废水中的六价铬，目的是研究pH（3-10），摇动时间（0.016-24h），吸附剂量（0.1）的影响。 –1.3 g L ^-1）和Cr（VI）的初始浓度（10–250 mg L ^-1）。在溶液pH值起主要作用的各种因素下研究了Cr（VI）的吸附，在pH 5.2时，茶渣生物炭（TWB）和稻壳生物炭（RHB）分别去除了99.3％和96.8％的Cr（VI）。 ， 分别。相比之下，TWB和RHB分别吸附了197.5 mg g ^-1和195.24 mg g ^-1 Cr（VI）和120 mg L ^-1初始Cr（VI）浓度。在接触时间研究中，2小时后，两种生物炭均达到平衡，这表明从水性介质中去除Cr（VI）是一个快速过程。动力学和等温线模型数据表明，伪二级模型和Langmuir（单层吸附）模型为两种生物炭上的Cr（VI）吸附提供了最佳拟合。根据FTIR ，–OH，COO–和–NH ₂官能团参与了Cr（VI）在生物炭上的吸附。由两种生物质产生的生物炭均能有效地从污水中去除六价铬，但是相比之下，TWB的吸附能力却略高于RHB。结论是，TWB和RHB可以为消除废水中的Cr（VI）提供一种经济有效的选择。