Photosensitized Oxidation of Cyanide in Aqueous Solutions of Photoactive Modified Hydroxyethylcellulose

Novel water-soluble polymeric photosensitizers based on a natural polymer, naphthalene-modified hydroxyethylcellulose (HENC), were obtained and used for the photooxidation of cyanide. The reaction leads to the formation of cyanate. The process occurs via photoinduced electron transfer from CN⁻ to the naphthalene or naphthoquinone polymeric chromophores. The kinetics of the reaction depend on the degree of substitution of HENC, its concentration, and pH of the solution. The polymers can be easily removed after reaction as prolonged irradiation leads to their photodegradation.