Remediation of complex remazol effluent using biochar derived from green seaweed biomass

The unique property of biochar, synthesized from a green seaweed (<i>Ulva lactuca</i>), to remediate complex Remazol dye bearing wastewater was investigated. Preliminary trials were targeted to explore the remediation capacity of biochar towards each of Remazol dyes (Remazol brilliant blue R (RBBR), Remazol brilliant orange 3R (RBO3R), Remazol brilliant violet 5R (RBV5R), and Remazol Black B (RBB)) in single-solute system. The results show that equilibrium pH played a vital part with maximum sorption observed at pH 2.0. The isotherm experiments confirmed that biochar exhibited high uptakes of 0.301, 0.292, 0.265, and 0.224 mmol/g for RBO3R, RBBR, RBV5R, and RBB, respectively. Due to the presence of multiple dyes as well as high concentration of auxiliary chemicals, the performance of biochar to remediate Remazol effluent was inhibited markedly compared to single solute systems. Nevertheless, the dye removal efficiency was above 77.5% and the decolorization rate was high with more than 95% of total dye decolorization completed within 240 min. Our results provide novel insights into the potential of biochar to remove Remazol dyes from complex dye wastewaters.

本研究针对以绿藻（Ulva lactuca）为原料合成的生物炭（biochar）的独特性能，探究其对含复合雷玛唑染料废水的修复效能。初步试验旨在探究生物炭在单溶质体系中对各雷玛唑染料的修复能力，所涉染料包括雷玛唑亮蓝R（RBBR）、雷玛唑亮橙3R（RBO3R）、雷玛唑亮紫5R（RBV5R）以及雷玛唑黑B（RBB）。结果表明，平衡pH值对吸附效果至关重要，在pH=2.0时吸附量达到峰值。等温吸附试验证实，生物炭对RBO3R、RBBR、RBV5R及RBB的吸附量分别可达0.301、0.292、0.265和0.224 mmol/g。由于废水中同时存在多种染料与高浓度助剂，与单溶质体系相比，生物炭对雷玛唑印染废水的修复性能受到显著抑制。尽管如此，染料去除率仍高于77.5%，且脱色速率较快，240分钟内即可完成总染料95%以上的脱色。本研究结果为生物炭去除复合染料废水中的雷玛唑染料的潜力提供了全新的科学认知。