Indian saffron – Turmeric (Curcuma longa) embedded supermacroporous cryogel discs for heavy metal removal
Cryogels are used in a variety of environmental and biotechnological processes. Cryogels are polymeric materials with large pores and open flow channels. Turmeric is a very popular spice, especially in India, which has been shown to contain curcumin alkaloids to treat a variety of many diseases. Playing a protective and therapeutic role against the diseases results from being able to bind to various targets. In this study, Indian saffron (Turmeric) embedded poly(2-hydroxyethyl methacrylate) cryogel discs (Tur-PHEMA/CDs) have been prepared to remove heavy metal ions from waste-water, which is a major environmental problem by utilizing the heavy metal binding property of turmeric. Tur-PHEMA/CDs were used to remove Cu(II), Pb(II), Cd(II) ions. Poly(2-hydroxyethyl methacrylate) cryogel discs (PHEMA/CDs) were also used as control polymer. The prepared cryogels are characterized by multiple experimental tests. The Tur-PHEMA/CDs and PHEMA/CDs with respectively swelling ratio of 83.6% and 71.2% were used in heavy metal ions adsorption studies. pH values of the solution were changed in the range of 3.0-6.0 to determine optimum pH. Maximum adsorption capacities of the Tur-PHEMA/CDs from aqueous solution were 18.36 mg/g for Cu(II), 8.99 mg/g for Pb(II) and 5.76 mg/g for Cd(II). The affinity order of heavy metal ions on mass basis was Cu(II) > Pb(II) > Cd(II) from synthetic wastewater. EDTA solution (0.5 M) was used for desorbing of heavy metal ions.