Photo-assisted electrochemical oxidation of imidacloprid in synthetic wastewater in the presence of chloride ions

Abstract

The pesticides from agricultural and industrial wastewater are recalcitrant to the physical and biological methods This study aims to examine the removal of imidacloprid (TOC0 = 100 ppm total nitrogen = 64 8 ppm) which is one of common pesticides through photo-assisted electrochemical treatment in solutions containing sodium chloride Operating variables included the dosage of chloride ions initial pH controlled pH current density temperature and light intensity The experimental results revealed that the degradation of imidacloprid followed a first order kinetic model Under optimal conditions: [NaCl] = 0 2 M (0 05-0 5 M) pH 5 5 (1 5-9 5) current density = 1 24 mA/cm2 (0-2 48 mA/cm2) 6 4 mW/cm2 (254 nm UVC irradiation) at 40 oC (20-40 oC) for 4 hours 98 4 % and larger than 99 % of TOC and nitrogen removal were obtained respectively Consequently the concentration of inorganic nitrogen - ammonia nitrate and nitrite - were lower than 1 ppm without the production of secondary pollutants after treatment

Date of Award	2017 Aug 7
Original language	English
Supervisor	Yao-Hui Huang (Supervisor)