$SnO_{2}$-Containing Clinoptilolite as a Composite Photocatalyst for Dyes Removal from Wastewater under Solar Light

Due to their adsorbent, ion exchange and catalytic properties zeolites are suitable for avariety of applications. We report on the photocatalytic activity of a readily available and inexpensivenatural zeolite clinoptilolite (Z) containing SnO2 (Sn-Z). The Sn-Z samples with 3–15 wt. % of Sn wereprepared by using a precipitation–deposition method. Powder X-ray diraction analysis showed thatthe zeolite structure was unaected by the introduction of the Sn-phase. Diuse reflectance UV/VISspectra of the Sn-Z samples confirmed the presence of SnO2 and X-Ray absorption spectroscopyanalyses suggested that the SnO2 particles mainly resided on the surface of the clinoptilolite, whileATR-FTIR analysis gave some clues that part of the SnO2 phase was incorporated in the pores ofthe zeolite. The presence of SnO2 in Sn-Z increased both adsorption capacity and photocatalyticperformance which could be partially explained by higher surface area and partially with an increasednegative potential of the surface. Adsorption and total degradation of methylene blue (MB) for theSn-Z with the highest amount of Sn (15 wt.%) was about 30% and 45%, respectively, suggesting asynergetic eect between SnO2 and the clinoptilolite lattice. Reusability tests showed that thesecatalysts present a promising material for water purification