Natural drinking water is often contaminated with toxic pollutants such as arsenic and fluoride, which pose severe health threats to the people living in the rural parts of India. Arsenic, in particular, is a known cancer-causing agent, or carcinogen, and can lead to lung, bladder, and skin cancer. Removing such pollutants from drinking water is therefore crucial.
Researchers from IIT Roorkee, India, have now proposed simple, low-cost solutions to this problem that employ novel adsorbent materials to remove arsenic and fluoride contamination from groundwater.
One of these solutions is modified ferromanganese slag, which removes arsenic by oxidizing its more toxic state to a less toxic and easily adsorbable form without adding any chemical to the solution or changing its pH levels undesirably. Furthermore, the material’s adsorption capacity remains unaffected by the pH levels.
The other solution is a hybrid adsorbent system comprising an adsorbent from laterite soil (ABTL) and aluminum oxide/hydroxide nanoparticle (AHNP) that is used to remove arsenic and fluoride in a customized adsorption column (filter unit). The system utilizes gravity and, therefore, can operate without power. Due to its high adsorption capacity, the adsorbents can be mixed in a desired ratio for tackling different concentrations of arsenic and fluoride.
These technologies can be applied for household as well as large-scale water purification.
Dr. Abhijit Maiti is an Associate Professor in the Department of Polymer & Process Engineering at IIT Roorkee, India. His research interests comprise design of secondary and tertiary water treatment systems, including polymeric membrane separation processes, adsorption, and other equipment design. He has been involved in the research of arsenic and fluoride removal from water for more than a decade. He has more than 40 peer-reviewed publications in various reputed international journals with over 1600 citations, four book chapters, one book, and three patents to his credit.
Dr. Prasenjit Mondal is a Professor in the Department of Chemical Engineering at IIT Roorkee, India. His areas of interest include energy and environmental engineering, water treatment, energy from biomass and wastes, separation processes, and waste plastics management. As a senior researcher, he has published 65 papers with over 3000 citations to his credit and has co-authored two books.
Natural drinking water often contains arsenic and fluoride, which are toxic pollutants that pose severe health risks to the rural population in India. Now, researchers from IIT Roorkee propose simple, affordable, and point of use techniques for water purification with two novel adsorbents: a modified ferromanganese slag that adsorbs arsenic species and an aluminum oxide/hydroxide nanoparticle adsorbent combined with ABTL, a laterite soil adsorbent. These compounds adsorb both arsenic and fluoride with the action of gravity.