| Summary: | 碩士 === 國立臺灣大學 === 化學工程學研究所 === 105 === Since H2 is a good energy carrier, photocatalytic water splitting and hydrogen production are promising technologies to provide renewable energy. Phenol is a kind of organic pollutants widely existed in industrial wastewater which has negative effect on environment and human health. As one of the advanced oxidation process, photocatalytic phenol oxidation is an efficient way to remove the phenol contaminant. Some researches coupled the two process above together, conducting the oxidation of phenol and reduction of H2O simultaneously. In this way, hydrogen is produced and phenol is degraded at the same time, which is a kind of dual-function reaction; however, the produced hydrogen was mixed with CO and CO2. In this research, Pt/STO:Rh was synthesized as hydrogen evolution photocatalyst by solid-state reaction method and photo-deposition method, and commercial WO3 was utilized as phenol oxidation photocatalyst. With the help of Fe3+/Fe2+ ions pair as electron mediators and the irradiation of 300 W Xe lamp, dual function reaction with initial phenol concentration of 200 μmol/L was conducted in a single batch reactor. The yield of hydrogen was 5.59 μmol/g at the 8th hour, and 13% of the phenol was removed, with CO2 as the main oxidation product. After that, the dual function reaction was conducted in a Twin reactor with a Nafion-117 membrane separating the two kinds of photocatalysts into different parts. Therefore, the shielding effect and competitive adsorption of light source were avoided and photocatalytic efficiency was raised. The yield of hydrogen is 11.37 μmol/g at the 6th hour, and the phenol removal is raised up to 22%. By the separation effect of Nafion membrane, 86.2% of the CO and 87.6% of the CO2 was simultaneously separated from hydrogen, decreasing the further cost of purification. Effect of phenol initial concentration (50 μmol/L to 200 μmol/L) on hydrogen evolution amount was investigated, and the results showed that with more phenol added, the hydrogen yield was raised. And the optimum phenol concentration is 200 μmol/L, which is 20% better than hydrogen yield of pure water splitting (9.94 μmol/g) under the same experiment conditions. Our study proved that the H2 production from water splitting can be significant enhanced via the oxidation of phenol.
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