photocatalytic degradation of humic acid by ag/zno nanoparticles under uvc irradiation from aqueous solutions

introduction: humic acid (ha) is one the original disinfection byproducts processors in water treatment. so, removing it is necessary before water chlorination. in the present study, photodegredation of humic acid in water using ag/zno nano particle under uvc irradiation in batch system was investigated. material and methods: photocatalytic study was carried out to evaluate the effect of uvc (15w), irradiation time of (10 - 40min), ph (5 - 9), initial humic acid concentration of (10-50 mg/l) and ag/zno dosage of (0.2 – 0.8 g/l) on humic acid removal. ha concentration was monitored spectrophotometrically by measuring the ha absorbance at 254 nm. results: ha removal efficiency was obtained 88% at ph 7, ag/zno dosage 0.6 g/l, initial humic acid concentration 25 mg/l and irradiation time 40 min. the removal of ha from aqueous solution increased by increasing irradiation time and decreasing initial ha concentration. also, the kinetic study was consistent with pseudo-first order reaction. conclusion: the results showed that photocatalytic degredation process using ag/zno nanoparticles can be used efficiently for ha removal from aqueous solutions.