Abstract:
Preparation of a metal adsorbent containing hydroxamic acid group from cellulose fiber grafted methyl acrylate by simultaneous irradiation technique was conducted. Major parameters put to study included: monomer concentration, solvent media concentration, total dose and dose rate. Cellulose from 100% cotton fabric of 150 g/cm2 was used as a trunk polymer. The optimum condition for grafting methyl acrylate onto cotton fabric was found to be as follows: grafting was performed in a solution of 45% MA (v/v) and methanolic solution (Methanol:H2O = 1:1) radiation dose of 50 kGy and dose rate of 0.1417 kGy/min. The degree of grafting at these conditions was 133 (6.63 mmol/g of MA group). Characterization of graft copolymers was done by FTIR spectroscopy, DSC and TGA. A study to determine the suitable condition for modification of ester functional group to hydroxamic acid group revealed the optimum condition to be: 25% (w/v) hydroxylamine solution in methanolic solution (Methanol:H2O = 5:1), pH of 13, 2 hours reaction time and temperature of 75C. This functionalization condition gave % conversion of 54. The adsorbent so obtained containing hydroxamic acid groups could adsorb cadmium and lead up to 90.59% and 91.29% at pH of 5.0 and 3.0 respectively, after coming into contact with 100 ppb of those heavy metals for 24 hours.