الفهرس | Only 14 pages are availabe for public view |
Abstract In this study, we studied the mechanisms of adsorption of common water pollutants as silver, copper and ferric cations using gellan and nanogellan (which is obtained from the bacteria Sphingomonas paucimobilis). The production of gellan sugar by different carbon and nitrogen sources. The effect of gellan and nanogellan gum in terms of concentration, acidity and re-adsorption, and the ionic force on the adsorption properties of the heavy metals, the gellan sugar was obtained in the production medium (12.6 g / l using sucrose, a source of carbon and ammonium nitrate, a source of nitrogen and a pH of about 6-7), the nanogellan were obtained in the size of 80-90 nm, the gellan sugar showed a strong capacity for adsorption up to 140.48 milligrams of silver / gm gellan and 167.00 mg / g of gellan, 75.94 mg / g of (Cu2+ and Fe3+/gm gellan gum respectively). While the nanogellan was higher, reaching 157.77 mg silver / g nanogellan, and 186.94 mg / g nanogellan, 92.67 mg / g of (Cu2+ and Fe3+/gm nanogellan, respectively). Infrared spectroscopy (IR) showed that hydroxyl, ketone and ether groups of gellan and nanogellan sugar were involved in the metal adsorption process, which are the main functional groups for bonding with metals. Sulfuric acid (0.1) showed a high degree of ability to disengage between sugar and metal from other solvents. The recovery rate (94-90 - 86%) was for ions (silver, copper and ferric) respectively, and the sugar can be reused in the process of adsorption seven times with high efficiency. |