A Review on Phytoremediati on of Heavy Metals and Utilization of Its Byproducts

Abstract

Abstract. This review presents the status of phytoremediation technologies with particular emphasis on phytoextraction of soil heavy metal contamination. Unlike organic compounds, metals cannot be degraded, and cleanup usually requires their removal. Most of the conventional remedial technologies are expensive and inhibit the soil fertility; this subsequently causes negative impacts on the ecosystem. Phytoremediation is a cost effective, environmental friendly, aesthetically pleasing approach most suitable for developing countries. Despite this potential, phytoremediation is yet to become a commercially available technology in India. This paper reports about the mobility, bioavaliability and plant response to presence of soil heavy metals. It classifies the plants according to phytoextraction mechanism and discusses the pathway of metal in plants. Various techniques to enhance phytoextraction and utilization of by-products have been elaborated. Since lot of biomass is produced during this process, it needs proper disposal and management. It also gives an insight into the work done by authors, which focuses on high biomass extractor plants. High biomas weeds were selected to restrict the passage of contaminants into the food chain by selecting non-edible, disease resistant and tolerant plants, which can provide renewable energy. Thus making phytoextraction more viable for present utilization.

Germination and growth of six plant species on contaminated soil with spent oil

“…An artificial soil was prepared for this experiment containing 85 % sand, 10 % silt and 5 % clay. This light loamy soil provides a suitable substrate for plant growth in phytotoxicity test as has been used by Adam and Duncan (2002), Anoliefo and Vwioko (1995) and avoids anomalies normally associated with natural soils Ghosh and Singh (2005). In order to provide a relatively inert substrate, the artificial soils were placed into autoclave (121°C ) for 30 minutes in two consecutive days.…”

“…White, et al, 2006;Jilani and Khan, 2006). This technology has been applied to both organic and inorganic pollutants present in soil (solid substrate), water (liquid substrate) or the air (Ghosh and Singh, 2005). In medium size cities such as Kermanshah with a population of approximately 600,000, the main sources of spent oil appears to be small unregulated enterprises.…”

Effect of biochar amendments on As and Pb mobility and phytoavailability in contaminated mine technosols phytoremediated by Salix

“…Among them, a few Brassicaceae have been described as PTE hyperaccumulators (Sarma, 2011). However, their low biomass and slow growth rate diminish their potential use in phytoremediation (Ghosh and Singh, 2005). To overcome these drawbacks, tree species, which present a rapid growth, a large biomass production, a deep root system and sometimes a high accumulation capacity for PTEs, are interesting phytoremediation options.…”

Economic Viability of Phytoremediation of a Cadmium Contaminated Agricultural Area Using Energy Maize. Part II: Economics of Anaerobic Digestion of Metal Contaminated Maize in Belgium

“…This time constraint may become less important if phytoextraction can be combined with a revenue earning operation (Robinson et al, 2003;Ghosh and Singh, 2005;Meers et al, 2005;. Decontamination of soil is a long term goal that can be achieved by striving for short term goals like producing renewable/green energy to keep the income of the farmers at a level comparable to the situation before the start of remediation (Vassilev et al, 2004).…”