Ionic Liquid-Functionalized Silver Impregnated Activated Carbon of Garlic Peel for Wastewater Treatment

The world is currently endeavoring to achieve Sustainable Development Goals (SDGs), the 2030 Agenda adopted in 2015 by the United Nations. SDG-06 and SDG-14 are focused on clean water and sanitation as well as safety of the life present below water making it critical to recognize the current wastewater treatment gaps. To assure the clean drinking water and protect the aquatic life, there is an increasing demand for efficient, sustainable and green sorbent with enhanced surface functionality. As part of this approach, this study is focused on the sorption of a cationic dye methylene blue (MB) onto a novel, ecofriendly nanocomposite (IL-NC) of garlic (Allium sativum) peel functionalized by ionic liquids-the green solvents, to mitigate the environmental and human health risks. Activated carbon of garlic peel was impregnated with silver nanoparticles prior to ionic liquid functionalization. Comprehensive characterization of IL-NC was carried out by FTIR spectroscopy, SEM imaging, TGA and XRD analysis. Various factors such as initial dye concentration, sorbent amount, contact time, temperature and pH were investigated to optimize the batch sorption process. Sorption data were interpreted by isothermal, kinetic and thermodynamic models. The data fitted well with Langmuir isotherm model and pseudo-second-order. The thermodynamic parameters suggested that sorption process is spontaneous, exothermic and reversible. The sorption-desorption cycles revealed the cost-effectiveness of the sorption process making it a commendable contributor toward water ecosystem restoration and responsible consumption of biomass.