Degradation of the insecticide dimethoate by solar photocatalysis at pilot plant scale

Titanium dioxide photocatalysis, using 200 mgl(-1) of TiO2, and photo-Fenton, using 20 mg l(-1) of iron, were applied to the treatment of dimethoate dissolved in water at 50 mg l(-1). A heterogeneous photocatalysis test was performed in a 35-1 solar pilot plant with Compound Parabolic Collectors (CPCs) under natural illumination. A homogeneous photocatalysis test was performed in a different solar pilot plant with four CPC units and a total volume of 75 1. In this work total disappearance of dimethoate and 90% of mineralization were attained in both solar treatments. Treatment time, hydrogen peroxide consumption and ferric phosphate precipitation during photo-Fenton treatment were discussed.