Joishar Deepak, Singh Netra Pal, Varathan Ezhilselvi, Singh Nahar
Chemical and Food BND section (BND Division), CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
ACS Omega. 2021 Aug 24;6(35):22570-22577. doi: 10.1021/acsomega.1c02324. eCollection 2021 Sep 7.
Crystal violet (CV) dye is one of the most toxic dyes majorly generated by textile industries. It may cause health issues if enters human beings. A lot of research has been reported for the removal of CV dye from wastewater; however, most of them are time-consuming and hardly remove more than 95% of the CV dye. In the last few years, we have tested several materials, and most of them have exhibited very low efficacy toward adsorption of CV including zinc peroxide (ZnO). To enhance adsorption efficacy, dispersibility, and stability, the surfaces of several reported materials were modified using different wetting agents and nonionic surfactants. Interestingly, ZnO, which was earlier very less effective after surface modification by sodium salt of dioctyl sulfosuccinate, efficiently adsorbed >99.5% of CV from contaminated water within 5 min of contact time at pH ∼10. The adsorption capacity obtained for the sodium docusate surface-modified zinc peroxide (ZnSD) adsorbent was found to be 123 mg/g, which is much better than the other reported for CV removal. Different physiochemical experiment parameters like pH, contact time, initial dye concentration, adsorbent dosages, and temperature were optimum to achieve maximum adsorption of the CV dye. The adsorption rate and adsorption mechanism studies show that the adsorption of CV follows pseudo-second-order kinematics and the Freundlich isotherm model. The adsorption results are consistent, and even treated water can be reutilized for various applications.
结晶紫(CV)染料是纺织工业产生的毒性最强的染料之一。如果进入人体,可能会引发健康问题。已有许多关于从废水中去除CV染料的研究报道;然而,其中大多数方法耗时较长,且很难去除超过95%的CV染料。在过去几年中,我们测试了几种材料,其中大多数对CV的吸附效果都非常低,包括过氧化锌(ZnO)。为了提高吸附效果、分散性和稳定性,使用不同的湿润剂和非离子表面活性剂对几种已报道材料的表面进行了改性。有趣的是,早期经磺基琥珀酸二辛酯钠盐表面改性后效果很差的ZnO,在pH值约为10的条件下,接触时间5分钟内就能从受污染水中高效吸附>99.5%的CV。发现十二烷基磺酸钠表面改性的过氧化锌(ZnSD)吸附剂的吸附容量为123 mg/g,这比其他报道的用于去除CV的吸附剂要好得多。不同的物理化学实验参数,如pH值、接触时间、初始染料浓度、吸附剂用量和温度,对于实现CV染料的最大吸附是最佳的。吸附速率和吸附机理研究表明,CV的吸附遵循准二级动力学和Freundlich等温线模型。吸附结果是一致的,甚至处理后的水还可重新用于各种应用。