Removal of Chromium from Tannery Wastewater Using Low-Cost Biosorbents: A Comparative Study of Pinus Sawdust, Teak Sawdust, and Rice Husk

https://doi.org/10.46610/JoEES.2026.v011i02.005

Abstract

Tannery industries are among the key sources of environmental pollution by industrial effluents, mostly contaminated with chromium. Chromium, particularly in the hexavalent state (Cr(VI)), represents an environmentally harmful substance, which is characterized by extreme toxicity, carcinogenicity, and persistence in various environmental media. Thus, in developing nations such as India, where tannery industries operate in huge numbers without any proper waste treatment infrastructure, chromium contamination of both surface and groundwaters is considered to be an important issue. Traditional treatment technologies, including chemical precipitation, ion exchange, and membrane filtration, are very effective in removing chromium ions from industrial effluents; however, their operation is associated with considerable expenses. Therefore, the aim of the current research paper is to analyze the possibility of using Pinus sawdust, Teak sawdust, and rice husk as biosorbents for the removal of chromium ions from tannery wastewater. All the biosorbents used in the study represent low-cost and sustainable alternatives to traditional water treatment approaches and have high efficiency in treating environmental pollutants. Batch tests were carried out in the laboratory using three different types of biosorbents under controlled conditions. The results obtained demonstrate that Pinus sawdust is the most efficient biosorbent for chromium removal from tannery wastewater (91.19%). Rice husk demonstrated a good efficiency as well (85.42%); this can be explained by the presence of many silanes in the structure. Also, Teak sawdust was effective (85.22%), which was related to the presence of phenols.