Study of removal of a textile dye turquoise industrial wastewater using synthetic zeolitic molecular sieves

Abstract

The zeolite molecular sieves have been continuously studied in processes involving heterogeneous catalysis and adsorption phenomena. The use of adsorption has been potentially applied in removing contaminants from waste from the textile industry. Zeolites studied in this work with structure FAU, BEA or MTW were characterized by physico-chemical techniques. The XRD diffraction patterns showed the presence of crystalline structure of zeolite BEA, FAU, MTW in the adsorbents. The FT-IR spectra showed bands due zeolitic structure. Studies of removal of reactive dye Turquoise were performed in acidic (pH 1), with a concentration of 50 ppm of synthetic wastewater using zeolites BEA, MTW and FAU forms ammonia and acid, and using the zeolites obtained. The percentages of removal were the most significant: 80%, 68% and 85% (FAU, BEA e MTW) e 83%, 78% e 83% (FAU, BEA e MTW), using acid and ammonia in the form of zeolites FAU, BEA and MTW, respectively. Reuse tests were performed and efficient results also were noted. Analyses using the raw wastewater showed results even more effective. The rates of removal were: 94%, 93%, 88% (FAU, BEA and MTW, ammonium form) and  95%,87% and 90% (FAU, BEA e MTW, acid form).