Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, P.D. Hills P.O., 686560, Kottayam, India.
Inter University Instrumentation Centre, Mahatma Gandhi University, P.D. Hills P.O., 686560, Kottayam, India; School of Environmental Sciences, Mahatma Gandhi University, P.D. Hills P.O., 686560, Kottayam, India.
J Hazard Mater. 2019 Mar 5;365:297-305. doi: 10.1016/j.jhazmat.2018.11.014. Epub 2018 Nov 5.
Layer by layer (LbL) assembly can be regarded as an emerging technology for the separation of organic micro-pollutants from water. Direct assembly of polyelectrolytes (PEs) under LbL mode on natural support material is rare. Here we report the integration of LbL to one of the most resourceful support materials that might have an enduring impact on water treatment in color industry. A low-cost adsorbent is developed from chitosan (CHI) and polyacrylic acid (PAA) through LbL deposition on coir fiber (CF) by alternate exposure to their aqueous solutions. Their layer dependent formation is characterized by spectroscopic and microscopic techniques. CHI/PAA multilayer coated coir fiber or simply, layered coir fiber (LCF) showed high loading of cationic and anionic dyes both at acidic and alkaline loading pH. The loading was between 70% and 99% at the acidic pH 3 which is attributed to the binding between LCF and dye molecules by electrostatic and hydrophobic forces. The performance of LCF in presence of NaCl, NaSO and sodium dodecyl sulfate (SDS) in dye solution is discussed. Textile industrial waste water showed significant reduction in dye (81%) content along with COD (84%) and TDS.
层层自组装（LbL）可被视为一种新兴的有机微污染物水分离技术。在自然支撑材料下直接进行 LbL 模式的聚电解质（PE）组装很少见。在这里，我们报告了将 LbL 集成到最具资源利用价值的支撑材料之一中，这可能会对色彩工业的水处理产生持久影响。通过在椰壳纤维（CF）上交替暴露于其水溶液，通过 LbL 沉积，由壳聚糖（CHI）和聚丙烯酸（PAA）制备了一种低成本的吸附剂。其层依赖性形成通过光谱和微观技术进行了表征。壳聚糖/聚丙烯酸多层涂覆的椰壳纤维或简单的层状椰壳纤维（LCF）在酸性和碱性负载 pH 下均显示出对阳离子和阴离子染料的高负载。在酸性 pH 3 下，负载量在 70%至 99%之间，这归因于 LCF 与染料分子之间通过静电和疏水相互作用的结合。讨论了 LCF 在染料溶液中存在 NaCl、NaSO 和十二烷基硫酸钠（SDS）时的性能。纺织工业废水显示出染料（81%）含量以及 COD（84%）和 TDS 的显著降低。
