Sunil Valand and Latesh Chaudhari
Abstract
The pulp and paper industry generates large amounts of wastewater, and its characteristics vary depending on the manufacturing process used. If this wastewater is not properly treated and disposed of, it can cause serious environmental and health problems due to the presence of organic and inorganic pollutants. Although conventional treatment methods such as ion exchange, reverse osmosis, electro dialysis, and ultra filtration are effective, their use is often limited by high operating and maintenance costs. Therefore, adsorption has gained attention as a simple, cost-effective, and efficient method for removing pollutants from industrial wastewater.This study focuses on the reduction of Chemical Oxygen Demand (COD) from pulp and paper mill effluents using sustainable adsorbents. Clay-based adsorbents, namely calcium bentonite, sodium Bentonite, Fullerâs earth, and natural zeolite, along with activated carbon, were evaluated at different dosages to compare their adsorption performances. These materials are readily available, inexpensive, and environmentally benign, making them suitable alternatives for sustainable wastewater treatment. The experimental results demonstrated effective COD removal by all adsorbents. Although activated carbon achieved the highest COD reduction, the performance of natural zeolite and Fullerâs earth was comparable, with activated carbon showing only approximately 8â10% higher COD removal efficiency than natural zeolite. The high cost of coal-based activated carbon has stimulated the search for economical alternatives. Sustainable adsorbents such as calcium bentonite, sodium bentonite, Fullerâs earth, and natural zeolite have significant potential for reducing pollutants in wastewater. The objective of this study was to investigate the adsorption process for reducing COD in pulp and paper industry effluent using sustainable clay-based adsorbents. Adsorption experiments were conducted using ETP inlet wastewater samples collected from a paper manufacturing industry. COD and percentage COD reduction were evaluated using different adsorbents under varying operating conditions, particularly with respect to the adsorbent dosage. The results indicate that natural zeolite can serve as an effective and economical alternative to activated carbon for COD reduction in pulp and paper wastewater treatment.