Abstract

Environmental pollution is an aggressive change in the surroundings mainly because of heavy metals, dyes and organic pollutants, which are responsible for crucial natural and health issues. The undiscerning industrial activities make the water resources inappropriate for utilization and the accumulation of these pollutants in water is accountable for harmful effects on aquatic plants and animals. An eco-benign approach was explored for the synthesis of silica nanoparticles (KW-NS) using waste aquatic weeds. In the present study, waste aquatic Kariba weeds were utilized to synthesize and characterize silica nanoparticles and to investigate their applicability in the removal of Cr(VI) ions from aqueous as well as industry effluent. The silica nanoparticles using Kariba weeds (KW-NS) were prepared using sol-gel method and characterized using SEM, FTIR and BET analysis. Various parameters such as pH, adsorbent dosage, initial metal concentration and contact time on the adsorption of Cr(VI) were investigated and optimized. Adsorption isotherm, kinetics, thermodynamics, and regeneration mechanism were studied to determine the efficacy of KW-NS. The adsorption equilibrium for Cr(VI) was achieved at an optimum pH of 4.3 with 4 g L^–1 adsorbent dosage at 60 min with 10 mg L^–1 metal ion concentration and maximum adsorption capacity reached up to 96.54 mg g^–1. The applicability of the synthesized KW-NS was checked with the tannery and electroplating industry effluent and posed 72 and 60% removal efficiency, respectively. Results obtained from this study indicate that the waste aquatic Kariba weed has the potential to synthesize silica nanoparticles in a more efficient and economical way than the conventional synthesis. These nanoparticles can be effectively applied as an adsorbent to treat industrial effluents for heavy metal removal.

中文翻译：

---

使用卡里巴杂草 (KW-NS) 的溶胶-凝胶法合成二氧化硅纳米粒子及其去除 Cr(VI) 的效率研究

摘要

环境污染是周围环境的剧烈变化，主要是由于重金属、染料和有机污染物造成的，这些都是造成关键的自然和健康问题的原因。无意识的工业活动使水资源不适合利用，这些污染物在水中的积累会对水生植物和动物造成有害影响。探索了一种利用废弃水草合成二氧化硅纳米粒子 (KW-NS) 的环保方法。在本研究中，利用废弃的水生Kariba 杂草合成和表征二氧化硅纳米粒子，并研究它们在去除水和工业废水中 Cr(VI) 离子的适用性。使用卡里巴杂草的二氧化硅纳米粒子(KW-NS) 使用溶胶-凝胶法制备，并使用 SEM、FTIR 和 BET 分析进行表征。研究和优化了各种参数，如 pH 值、吸附剂用量、初始金属浓度和接触时间对 Cr(VI) 的吸附。研究了吸附等温线、动力学、热力学和再生机制，以确定 KW-NS 的功效。Cr(VI) 的吸附平衡是在 4.3 的最佳 pH 值和 4 g L ^–1吸附剂用量下在 60 分钟内达到的，金属离子浓度为 10 mg L ^–1，最大吸附容量达到 96.54 mg g ^–1. 合成的 KW-NS 的适用性通过制革和电镀工业废水进行了检查，去除率分别为 72% 和 60%。从这项研究中获得的结果表明，废弃的水生卡里巴杂草有可能以比传统合成更有效和更经济的方式合成二氧化硅纳米粒子。这些纳米颗粒可以有效地用作吸附剂来处理工业废水以去除重金属。