New composite TiO2/naturals gums for high efficiency in photodiscoloration process

摘要

A novel TiO2 photocalayst was synthesized by sol-gel method in the presence of Arabic (AGTi) and Karaya gums (KGTi). The composites were structurally and morphologically characterized by different techniques and the photocatalytic activity was investigated using methylene blue (MB) dye as model pollutant. In addition, the stability, recycle, effect of scavengers, and toxicity were investigated. The composites presented spherical structure and the nucleation of TiO2 particles was modified in presence of the gums. All the materials showed presence of the anatase phase and the textural properties indicated mesoporous and high surface area. The band gap was approximately 2.9 eV for the both materials; however the recombination process was more favored in KGTi. The C/C-0 ratio of AGTi and KGTi decreased after 150 min of radiation. The electron plays the dominant role in photocatalytic process in both composites. The photocatalysts demonstrated stability after 3 runs and toxicity was not evidence in both composites. Hence, the composites showed excellent photocatalytic performance for MB discoloration.