Bottle Gourd (Lagenaria vulgaris) Shell as a Natural, Biodegradable, Highly Available, Cheap, Agricultural by-Product, Miscellaneous Biomass, Ion Exchanger, Biosorbent and Fertilizer

Abstract

The increased interest in natural, renewable, biodegradable, easily available, low-cost materials makes agricultural residues, such as lignocellulosic biomass, attractive raw materials for the preparation of effective biosorbents for various pollutants (metal ions, anions, dyes, pharmaceutical degradation products, metabolites, organic macromolecules) for the wastewater treatment. Various covalent and non-covalent modification approaches significantly improve the sorption properties of these lignocellulosic functional particles, even improving their dispersion in hydrophobic polymer matrices, associative properties in water, rheological properties, surface-active properties, which can control the sorption of various ionic pollutants both in batch and in flow mode. Advantages over commercial sorbents (techno-economic aspect, no secondary pollution, usability as fertilizers), easy separation from the sorption medium, microstructural properties (strength, porosity, interactivity, stability), as a promising and sustainable biosorbent highlight the environmentally friendly bottle gourd shell. On the example of this biosorbent, the conventional approach to the pollutant sorption process (comparative kinetic, thermodynamic and equilibrium tests) was improved, as well as its shortcomings in predicting optimal process parameters. To fill the gaps of the already unnecessary numerous experiments, a design study involving OVAT experimental approaches integrated with DoE methodology was conducted. This integrated experimental design was implemented in the optimization of the pollutant sorption process.