Modification and regulation of acid-activated kaolinite with TiO2 nanoparticles and their enhanced photocatalytic activity to sodium ethyl xanthate

High photocatalytic activity composites of TiO2/acid-activated kaolinite (T/AK) were optimally constructed utilizing a simple hydrothermal method for the high-performance photocatalytic degradation to sodium ethyl xanthate (SEX) in mineral processing wastewater in this work. The synthesized T/AK composites under different preparation conditions were characterized by SEM, TEM, XRD, XPS, and UV-vis DRS to determine their structure, morphology, elemental composition, and photochemical properties. Compared with pristine TiO2 and kaolinite, the T/AK composites exhibited enhanced photocatalytic degradation performance to SEX due to their synergistic effects of adsorption and catalysis. The photocatalytic degradation efficiency of 0.4 g/L of 0.6T/AK composites to 30 mg/L of SEX reached 94% in 50 min under optimal preparation conditions, demonstrating that T/AK composites photocatalysts could effectively degrade toxic and corrosive SEX. The active radical studies revealed that the most significant active component in the photocatalytic system is h+ . The enhanced photocatalytic activity originated from its large specific surface area and suppressed the recombination rate of the photogenerated carriers of T/AK composites, which makes them great potential in wastewater treatment of mineral processing.