Synthesis of La0.8Zn0.2MnO3 nanocatalysts for decomposition of VOCs in a DBD plasma reactor; Influence of sol-gel parameters

Abstract

In this study, La0.8Zn0.2MnO3 nanocatalysts were synthesized using sol-gel method at different citric acid to metal nitrate (C/N) ratios and different calcination temperatures. The synthesized catalysts were used for oxidation of benzene, toluene, and xylene (BTX) in a catalytic-plasma hybrid reactor at different input voltages of 5, 7.5, 10, 12.5, and 15 kV. The synthesized catalysts were analyzed by XRD, FESEM, EDX, FTIR, BET, and TEM. XRD analysis confirmed the effect of calcination temperature on crystalline degree of LnMnO3 phase in perovskite La0.8Zn0.2MnO3 catalyst. TEM analysis also confirmed production of particles in nanometer range. Moreover, FTIR and BET analyses indicated that C/N ratio has a direct effect on the amount of metal oxide functional groups and surface area of the resultant catalyst, respectively. The reactor tests showed that the use of C/N= 0.5 and calcination temperature of 700°C in catalyst preparation resulted in the best performance in BTX oxidation. Increasing the voltage up to 15 kV had a good effect on the oxidation ability of the catalyst as well. In these conditions, the highest oxidation percentages of benzene, toluene and xylene were equal to 90.00, 89.86, and 88.64 %, respectively.