Environmental applications of Luffa cylindrica-based adsorbents

Abstract Adsorption is considered to be a simple, low cost, and effective technique to decontaminate polluted (waste)water. A lot of research has been done on the application of commercial activated carbon, a traditional adsorbent, that gives satisfactory results but its application is restricted due to high commercial costs. For this purpose, researchers, based also on the concept of green chemistry and circular economy, turn their efforts to finding other adsorbents that are economical, eco-friendly, and abundant. Luffa cylindrica has many applications in medicinal, industrial, and cosmetic sectors. This review article focuses on the alternative use of Luffa biomass (prior and after chemical modification) in the (waste)water treatment process. Specific emphasis is given to the effect of adsorption parameters (such as initial concentration, solution pH, contact time, that affected the adsorption process and on the thermodynamic of the adsorption. Adsorption isotherms and kinetic modeling are also presented and discussed. The adsorption capacities estimated to lie between 2.335 mg/g and 714 mg/g for toxic metals, 9.63 mg/g and 210.97 mg/g for dyes, and 9.25 mg/g and 278 mg/g for emerging pollutants.