Remediation of Arsenic in Water Using Unique Ashed Biomass Material

Abstract

The contamination of the world’s water supply due to various contaminants has caused the clean water supply to shrink around the globe. The problem is not only an issue with developing nations; in fact, many developed countries are facing the same turmoil. With the globalization, industrialization and weak enforcement of environmental regulations, waste water is discharged into clean water resources whereby contaminating the water. Out of the long list of contaminants many heavy metals find their way into the clean drinking water supply. The heavy metals arsenic (As), lead (Pb), and mercury (Hg) as well as many others are also discharged into water resources. There are numerous methods for removal of these heavy metals from water including filtration, chemical precipitation, ion exchange, adsorption, electro deposition as well as others but most are expensive and or not completely satisfactory. Arsenic and its compounds are often used as pesticides, herbicides, insecticides and various alloys and often find their way into the drinking water supply through various industrial sources. A cost-effective remediation of arsenic in water using readily available material is urgently needed. An ashed waste material consisting primarily of Azadirachta indica (Neem leaves) and Mangifera indica (Mango leaves) has been found effective in removing both arsenic (III) and (V) from water. The utilization of this ashed material achieves the concept of using waste material from one source, used by another and therefore benefiting both. The adsorbent is very effective at pH =7 and ion exchange appears to be the major adsorption mechanisms for binding the metal ions to the plant ash material. The material shows sufficient operation capacity to indicate the possibility of its use in remote rural areas as well as in an urban water treatment facility.