Effect of Bifunctional Isocyanate Linker on Adsorption of Chromium(VI) Diphenylcarbazide Complex onto b-Cyclodextrin

Chromium is one of the toxic heavy metals and is a major pollutant in wastewater. The chromium is originates from widespread use in various industries such as metallurgical, refractory and chemical. Chromium exists in two stable oxidation states, Cr(III) and Cr(VI). Both of them have drastically different charge, physicochemical properties as well as chemical and biochemical reactivity 1 . Cr(VI) exerts toxic effects on biological systems and exposure to hexavalent Cr compounds leads variety of clinical problem. It can cause perforation of the nasal septum, asthma and bronchitis. It also causes health disorders, such as vomiting and hemorrhage 2 . It is known to be carcinogenic and mutagenic which induces dermatitis. The maximum level permitted in wastewater is 5 ppm for Cr(III) and 0.05 ppm for Cr(VI) Due to the extreme toxicity of Cr(VI), its selective determination and removal from wastewater is of particular concern.