Supermacroporous hybrid polymeric cryogels for efficient removal of metallic contaminants and microbes from water

A supermacroporous cryogel column of chitosan-dimethylaminoethyl methacrylate (DMAEMA)-magnetite has been synthesized. The cationic and magnetic properties of chitosan/DMAEMA and magnetite, respectively, allow the adhesion of metals and microbes to the matrix. The large interconnected pores (20-100 mu m) with porosity greater than 85% of the cryogels facilitate fast water movement. At lab scale (approximately 2mL bed volume), static binding capacity of 100% (load: 4.5ppm arsenic and 2300ppm chromium) and dynamic binding capacity of 65% for arsenic (load: 58ppm) was observed. The binding capacity at pilot scale (approximately 300mL bed volume) was found to be 11.5mg arsenic and 14.22mg chromium. There was 100% binding of microbes (Escherichia coli and Streptococci) both at lab and pilot scale. The results were propitious and indicated the suitability of cryogel filter as a single device for the removal of arsenic, chromium, and microbes in field samples.