advanced oxidation of high concentrations of formaldehyde in aqueous solution under fluorescent and uv light

Background: formaldehyde (fa) is a carcinogen compound, which is soluble in water. fa can be removed from aqueous solution using advanced oxidation methods. methods: in this study, the oxidation of fa was studied under fluorescent and uv light. hydrogen peroxide (h_2o_2) was used as an oxidant. the ph value and h_2o_2 amount of samples were optimized. the chemical oxygen demand (cod), fa concentration, and h_2o_2 consumption were followed. results: it was observed that the ph value of the sample was more significant under fluorescent light than uv light at oxidation of fa. the highest cod removal and h_2o_2 reduction were 18.57 and 30.90%, respectively, at ph 12.00, with a 1:1 ratio of fa:h_2o_2 under fluorescent light. 86.41% fa and 62.12% cod removal were achieved at ph 7.00, with a 1:2 ratio of fa:h_2o_2, under uv light. it was observed that h_2o_2 was consumed at all ph values under uv light. on the other hand, under fluorescent light, the concentration of h_2o_2 decreased only at ph 12. in control samples containing only h_2o_2, the h_2o_2 reduction was 92.09% at ph 11.91, while it was 26% at other ph levels under fluorescent light. the h_2o_2 reduction changed between 33 and 44% at different ph values under uv light. the oxidation of fa was found to be suitable for the pseudofirstorder kinetic model and langmuir isotherm model. conclusion: the most effective oxidation was obtained at the original ph value (7.00) and 1:2 ratio of fa:h_2o_2 under uv light.