The present study elaborates the use of sagwan sawdust biochar as an efficient adsorbent for Cr(VI) abatement. Effect of experimental variables like solution pH (2–10), initial Cr(VI) concentration (30–100 mg/L), temperature (30–40 °C), adsorbent dose/Cr(VI) concentration (16.67–200), and contact time (10–80 min) was studied through batch operations. The optimization and interaction study for process parameters was done by employing response surface methodology through Box-Behnken design. The optimized condition for the maximum adsorption was pH 2.07, temperature 30.72 °C, and dose/Cr(VI) concentration 160.93. The surface characteristics of the adsorbent were evaluated via pH_zpc, FTIR, BET surface area, SEM-EDS, XRD, and XPS analysis. Functional groups like O-H, C-O, C-H, and C=O were responsible for the adsorption process, and change in the oxidation state of Cr was affirmed by XPS survey. The Cr(VI) adsorption was governed by second-order kinetics and the Langmuir isotherm with Q₀ of 9.62 mg/g. The thermodynamic study revealed the process to be exothermic and spontaneous. Mass transfer studies confirmed film diffusion to be favorable in the adsorption process. Adsorption occurred via electrostatic and physical attraction, reduction, and complexation. Therefore, the results suggest sagwan sawdust biochar is satisfactory and effective in removing Cr(VI) from aqueous solution.

本研究阐述了使用sagwan锯末生物炭作为减少Cr（VI）的有效吸附剂。实验变量的影响，例如溶液的pH（2–10），初始Cr（VI）浓度（30–100 mg / L），温度（30–40°C），吸附剂剂量/ Cr（VI）浓度（16.67–200） ，并通过批量操作研究了接触时间（10-80分钟）。通过Box-Behnken设计采用响应面方法对工艺参数进行了优化和交互研究。最大吸附的最佳条件是pH 2.07，温度30.72°C和剂量/ Cr（VI）浓度160.93。通过pH _zpc评估吸附剂的表面特性，FTIR，BET表面积，SEM-EDS，XRD和XPS分析。OH，CO，CH和C = O等官能团是造成吸附过程的原因，并且XPS调查证实了Cr氧化态的变化。Cr（VI）吸附受二级动力学和Langmuir等温线控制，Q ₀为9.62 mg / g。热力学研究表明该过程是放热的并且是自发的。传质研究证实膜扩散在吸附过程中是有利的。吸附是通过静电和物理吸引，还原和络合发生的。因此，结果表明，Sagwan锯末生物炭在从水溶液中去除Cr（VI）方面令人满意且有效。