Environ Technol. 2014 May-Jun;35(9-12):1436-53. doi: 10.1080/09593330.2013.870234.
This work proposes the use of agro-industrial wastes, specifically peanut hull (HP) and orange peel (OP), as adsorbents for dyes, such as Remazol Golden Yellow RNL-150% (RYG), Gray Reactive BF-2R (RG) and Reactive Turquoise Q-G125 (RT). Characterization by Brunauer-Emmett-Teller indicates that the adsorbents are mesoporous, with pHzpc values of 5.0 for HP and 4.0 for OP. Fourier transform-infrared spectroscopy identified carbonyl and sulphonic groups. The initial pH of the best-adsorbing solution of the three colours was 2.0. Increasing the concentration of the adsorbent promoted an increase in the percentage of removal until saturation of the adsorbent. In a factorial design, the largest value of q was obtained with 0.25 g of the adsorbent, with a particle size of < 0.4 mm and a stirring speed of 300 rpm. Such conditions were used in kinetic studies and studies of adsorption equilibrium. The evolution kinetics were rapid in the first few minutes, and after 180 min the system reached equilibrium. The kinetic model that best fit the experimental data to a 95% confidence level for the F test was the pseudo-second-order model for RYG/HP, RG/OP and RT/OP. There was no significant difference between the kinetic models as evaluated by the F test for RYG/OP, RG/HP and RT/HP. The experimental results indicated favourable dye adsorption characteristics for the adsorbents studied. The results of the F test showed that for RYG and RG, there was no significant difference between the two evaluated models. This study suggests that HP and OP are viable alternatives for the treatment of effluents containing RYG, RG and RT dyes.
本工作提出利用农业工业废物，特别是花生壳 (HP) 和橙皮 (OP)，作为染料的吸附剂，如 Remazol Golden Yellow RNL-150% (RYG)、Gray Reactive BF-2R (RG) 和 Reactive Turquoise Q-G125 (RT)。比表面积和孔径分布分析表明吸附剂为中孔材料，pHzpc 值分别为 5.0（HP）和 4.0（OP）。傅里叶变换红外光谱鉴定出了羰基和磺酸基。三种颜色最佳吸附溶液的初始 pH 值均为 2.0。增加吸附剂浓度可提高去除率百分比，直至吸附剂达到饱和。在析因设计中，当吸附剂用量为 0.25 g、粒径 < 0.4 mm、搅拌速度为 300 rpm 时，q 值最大。在动力学研究和吸附平衡研究中采用了这些条件。动力学研究表明，在前几分钟内，反应快速进行，180 min 后体系达到平衡。在置信水平为 95%的 F 检验中，对于 RYG/HP、RG/OP 和 RT/OP，拟二级动力学模型最适合于实验数据。对于 RYG/OP、RG/HP 和 RT/HP，F 检验表明动力学模型之间没有显著差异。实验结果表明，所研究的吸附剂对染料具有良好的吸附特性。F 检验结果表明，对于 RYG 和 RG，两种评价模型之间没有显著差异。本研究表明，HP 和 OP 是处理含 RYG、RG 和 RT 染料废水的可行替代品。
