Using the Clinoptilolite type of Zeolite modified with Magnesium Chloride, the influence of pH and exposure time on the percentage of removal of Pb2+ and Cd2+ in aqueous solutions in a closed system, was determined. The zeolites provided from Ecuador, were washed with deionized water and dried at 350°C to remove water from the interior of the structure, then the modification was carried out with Magnesium Chloride in a ratio by weight of MgCl2 / Zeolite = 2.5. The purpose of the modification was to increase the pore diameter and the surface area of the zeolite and thus obtain improved results. With the modified zeolite, adsorption tests were carried out, obtaining the highest percentage of removal of Pb2 + "97%" at a pH = 4 over a time of 180 min. For Cadmium the same trend was observed with pH, but the time at which the zeolite was saturated was 40 min, thus obtaining 77% Pb2 + removal...