Low-Cost Adsorbents: Growing Approach to Wastewater Treatment—a Review

Abstract

Industrial, agricultural, and domestic activities of humans have affected the environmental system, resulting in drastic problems such as global warming and the generation of wastewater containing high levels of pollutants. As water of good quality is a precious commodity and available in limited amounts, it has become highly imperative to treat wastewater for removal of pollutants. In addition, the rapid modernization of society has also led to the generation of huge amount of materials of little value that have no fruitful use. Such materials are generally considered as waste, and their disposal is a problem. Also, there are some materials that are available in nature that have little or no use. The utilization of all such materials as low-cost adsorbents for the treatment of wastewater may make them of some value. An effort has been made to give a brief idea of an approach to wastewater treatment, particularly discussing and highlighting in brief the low-cost alternative adsorbents with a view to utilizing these waste/low-cost materials.

KEY WORDS:

• activated carbon
• adsorption
• low-cost adsorbents
• pollutants
• wastewater treatment

ACKNOWLEDGMENTS

The authors thank the Indian Institute of Technology Roorkee, Roorkee, India, and FCT (Fundação para a Ciência e a Technologia), Lisbon, Portugal, for the award of a post-doctoral grant (number SFRH/BPD/20535/2004) and to the European Commission (Project ALFA-II-0412-FAFI) for financial support.