Purification of textile wastewater by collective degradation using nanorods of cesium titanium bromide (CsTiBr3) perovskite

Abstract

The present work recommends a sustainable environmentally safe method for the removal of textile dyes in an economically viable way.The wastewater expelled from the textile dying units contains a mixture of dyes. Here we address the challenge of using a single catalyst for the collective photocatalytic degradation of mixture of six dyes and two samples of textile effluents collected from a local dying unit under direct sunlight. The lead-free perovskite of CsTiBr₃ nanorods prepared via the solvothermal process is effective in the collective photocatalytic degradation of dye mixture containing toxic dyes like congo red, crystal violet, malachite green, methylene blue, rhodamine, and methyl orange. The six-dye mixture turned colorless within three hours of direct sunlight exposure. The collective photocatalytic degradation ability of CsTiBr₃ perovskite nanorods is successfully exploited for the degradation of the textile effluents. The chemical oxygen demand (COD) analysis guarantees the degradation of dye into non-toxic components. The recycling of wastewater is made possible by the removal of CsTiBr₃ catalysts through adsorption using biochar derived from invasive plants. The biochars are extracted from invasive plants such as Acrostichum Aureum, Alternanthera bettzickiana, cyclosorus interrupts, and Quisqualis indica in which Acrostichum Aureum showed maximum adsorption. The scavenger studies using isopropyl alcohol (IPA), ethylene diamine tetra acetic acid (EDTA), and silver nitrate (AgNO₃) suggest that holes control the photocatalysis mechanism.