Removal of naphthol green B and indigo carmine from wastewater by wheat bran and urea-modified rice husk

Abstract

Dye-related water contamination is a profound environmental issue, primarily because of the toxic nature of dyes and their harmful effects on living organisms. These pollutants can have severe consequences for ecosystems and human health. In response to this challenge, natural adsorbents have emerged as a highly promising solution. The novelty of my work lies in the use of wheat bran and urea-modified rice husk as biosorbents for the removal of naphthol green B and indigo carmine dyes from wastewater. While agricultural waste materials have been explored for wastewater treatment and rice husk modification with urea to enhance adsorption capacity is a unique approach. This innovative method offers a cost-effective and environmentally friendly solution for treating dye-contaminated wastewater, contributing to sustainable wastewater management practices. Their cost-effectiveness, ease of application, and high removal efficiency make them attractive options for mitigating dye pollution. The results are notable, with wheat bran and urea-modified rice husk achieving removal rates of 96% and 98% for naphthol green b, respectively. Similarly, indigo carmine removal rates reached 92% and 91% with wheat bran and urea-modified rice husk, respectively. Using Fourier transform infrared spectroscopy and scanning electron microscopy, various mechanisms behind the adsorption process of both dyes onto the adsorbent’s surfaces have been uncovered. These mechanisms encompass electrostatic interactions and the active roles of functional groups. The study results underscore that wheat bran and urea-modified rice husk are not just cost-effective but also highly efficient adsorbents for removing acidic dyes from wastewater.