| Summary: | 碩士 === 國立中正大學 === 化學工程研究所 === 89 === VOC(Volatile organic compounds) is toxic for environment and human, especial for our breath system. From the previous research, the hydrophobic character of Pt/Zeolite is bad .So we need stricter operation condition to remove VOC completely. And Pt/Zeolite is not suited for wasted water with high ion concentration. Because they will destroy the structure of Si/Al. Pt/SDB has the best hydrophobic character, but SDB is polymer structured and is easy to be corroded by acid/base solution. It’s also not suitable for high concentration wasted water because local heat and can’ be removed and that will coke product. In order to solve this problem we develop the catalyst —Pt/Active carbon. First, we used the impregnation to incipient wetness to prepare the catalyst, then we analyst the best temperature of oxidation and reduction. We discover that we continuously increased the operation temperature and pressure, we found that the activity of catalyst decreased .When the operation condition is 200℃,20atm,the support of catalyst have some crack phenomena .So we know the stability of catalyst is decreased .When the operation was 250℃,40atm,we found the activity of catalyst decreased very fast from the stability test. We also found the used catalyst all become powder. From EXAFS analyzing, we found that when the operation condition are 20 atm,200℃ and 40 atm,250℃,the situation of metal migration became quite serious. So we can conclude the factor of catalyst decay; one is that the Active carbon cracked when the reaction proceeded, the other is the metal migration. From the picture of white line of used catalyst and fresh catalyst, we can figure out the mechanism of catalytic wet air oxidation; Pt molecule is adsorbed by oxygen and then oxidizes VOC, instead of forming PtO2 bonds.
|
|---|
