This work aims to present a study of the adsorption and photocatalytic reduction of Cr(VI) by ZnAl, MgZ-nAl and MgAl mixed oxides derived from layered double hydroxides (LDHs). The effect of variables like Zn content and pH (3 and 6.5) on Cr(VI) removal efficiency is presented. The catalysts were characterized by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The reaction progress was verified by UV/vis spectrophotometry with a colorimetric method. A maximum of 99.5% Cr(VI) was photocatalytically removed and this process was approximately two times faster than adsorption. In addition, it was found that the use of these materials does not imply the addition of further chemicals to regulate pH since the free basic pH of the catalyst-contaminant suspension positively affects both adsorption and photo-reduction kinetics. (C) 2013 Elsevier B.V. All rights reserved.