Development of a wastewater treatment system contaminated with Cr (VI) through vegetable biomass modified with TIO2

Abstract

Research from around the world highlights the importance of creating affordable and simple industrial wastewater treatment systems to preserve water resources. The absence of such systems can have serious consequences. For example, the release of chromium (VI) from industries such as tanneries pollutes water bodies, often causing irreversible damage. The mechanical properties, low acquisition cost, and abundance of aquatic plant biomass of E crassipes make it a viable option for Cr (VI) removal. Furthermore, the addition of TiO₂ to plant biomass increases the amount of functional groups that contribute to high removal of heavy metals, including Cr (VI), providing an economical and efficient material for a novel industrial water treatment. The objective of this study is to create water treatment systems using TiO₂ treated E crassipes root waste powder. Removal data were collected from two fixed bed columns operating in series, treating about 4 L of water, removing 99% of the Cr (VI) present. Design parameters for a larger scale treatment system were modeled and validated using internal and external particle and mass balance models. Column reusability was evaluated by EDTA elution studies, adding all cycles, the total adsorption capacity was 69 mg/g. A full-scale treatment system was designed and developed using these models under effluent conditions similar to those found in the tanning and painting industries. The strategy proposed in this work allows compliance with environmental regulations through the use of green biotechnologies and mathematical and statistical reliability models. This tool is of vital importance in the concept of circular economy.

Graphical abstract