The hexavalent chromium removal from solutions of anionic surfactant (LAS) by granular activated carbon (GAC) commercial was studied. At CAG characterization was used ASTM standard method (Sauter mean diameter, dDMS e pH) and method BET (S, specific surface area). Adsorbent surface group and PCZ were determined by the method of Boehm and potentiometric titration, respectively. The adsorbent characterization results: dDMS=2.4 mm, pH=9.0,S=677.4 m²/g; basic groups (70%) compared with the acidic groups and PCZ in the range (4.8 – 8.6). Tests of adsorption of the surfactant LAS were carried out in shaker (140 rpm/24 h./27ºC), 2.0 g CAG/50 mL, the LAS concentration were determined by methylene blue standard method. The removal results versus initial concentration and removal versus time of all LAS concentrations were more than 99%. The adsorption of Cr(VI) (5 – 20 mg/L) were carried out in thermostatic bath (140 rpm/27ºC); 2,0 g CAG/50 mL; 1 and 24 hours of processing; without and with addition of surfactant (70, 140, 210, 280, 350, 533 and 700 mg/L). The initial e residual concentrations of metal were determined by 1,5-diphenylcarbazide colorimetric method. The metal removal without the addition of LAS was not satisfactory values were obtained, around 15%. The metal removal with surfactant reached values, around 70% to the lowest metal concentration (5 mg/L) and between (58-65%) for the other concentrations.
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