Noman Abdullah-Al, Shoudho Kishan Nandi, Shawon Zayed Bin Zakir, Alam Mohammad Khurshed, Ahmed Shoeb, Khan Iftheker Ahmed
Department of Chemical Engineering, Bangladesh University of Engineering and Technology Dhaka-1000 Bangladesh
Department of Mathematics and Natural Sciences, Brac University Dhaka-1212 Bangladesh.
RSC Adv. 2025 Aug 21;15(36):29528-29543. doi: 10.1039/d5ra03754a. eCollection 2025 Aug 18.
Hexagonal boron nitride (h-BN) was structurally modified using a simple and efficient chemical weathering method and assessed for its ability to remove anionic Congo Red (CR) and cationic Neutral Red (NR) dyes from wastewater. Batch sorption experiments explored variables including solution pH (2-12), modified h-BN dosage (0.25-1.0 g L), contact time (10-420 min), and dye concentration (10-500 mg L). Detailed characterization revealed the integration of hydroxyl groups, distinctive rough and cracked surfaces, increased interlayer spacing and crystal size, monodispersed stable solution, and enhanced solubility of modified h-BN. Optimal dye removal occurred at 0.5 g per L dosage, with CR achieving 99.23 ± 0.06% efficiency at pH 2 (60-90 min) and NR 85.77 ± 1.51% at pH 11 (90-120 min) in deionized water. Electrostatic interactions between the modified h-BN and dye molecules drove pH-dependent adsorption, following a pseudo-second-order kinetics model, indicative of chemisorption. Langmuir isotherms confirmed monolayer adsorption on homogeneous surfaces. For similar parameters, in a mixed dye system (, CR : NR = 1 : 1), the removal efficiency favored at pH = 2 over pH = 11 (, 80.54 ± 1.16% over 60.83 ± 5.18%)-was less than mono-dye systems-which indicates that more CR dye could be removed with the exact adsorbent dosage. A limited study was performed with clarifier inlet textile wastewater, which showed a decrease in removal efficiency compared to deionized conditions. A steady decrease in removal efficiency was observed while performing adsorption-desorption cycles. The results demonstrate the potential of modified h-BN as an adsorbent in dye removal from industrial wastewater.
采用简单高效的化学风化方法对六方氮化硼（h-BN）进行结构改性，并评估其从废水中去除阴离子型刚果红（CR）和阳离子型中性红（NR）染料的能力。批次吸附实验探究了包括溶液pH值（2 - 12）、改性h-BN用量（0.25 - 1.0 g/L）、接触时间（10 - 420分钟）和染料浓度（10 - 500 mg/L）等变量。详细表征揭示了羟基的整合、独特的粗糙和开裂表面、层间距和晶体尺寸的增加、单分散稳定溶液以及改性h-BN溶解度的提高。在每升0.5克的用量下实现了最佳染料去除效果，在去离子水中，CR在pH值为2（60 - 90分钟）时去除效率达到99.23±0.06%，NR在pH值为11（90 - 120分钟）时去除效率达到85.77±1.51%。改性h-BN与染料分子之间的静电相互作用驱动了pH值依赖的吸附，遵循准二级动力学模型，表明是化学吸附。朗缪尔等温线证实了在均匀表面上的单层吸附。对于类似参数，在混合染料体系（CR∶NR = 1∶1）中，pH = 2时的去除效率优于pH = 11时（分别为80.54±1.16%和60.83±5.18%），但低于单染料体系，这表明在相同吸附剂用量下可以去除更多的CR染料。对澄清器入口纺织废水进行了有限的研究，结果表明与去离子水条件相比去除效率有所降低。在进行吸附 - 解吸循环时，观察到去除效率稳步下降。结果证明了改性h-BN作为吸附剂从工业废水中去除染料的潜力。
