title: Application of aluminum-supported Pd, Rh, and Rh-Pd nanoparticles in supercritical carbon dioxide system for hydrodebromination of polybrominated diphenyl ethers.
abstract: Al-powder-supported Pd, Rh, and Rh-Pd catalysts were synthesized through a spontaneous redox reaction in aqueous solutions. These catalysts hydrodebrominated 4- and 4,4'-bromodiphenyl ethers in supercritical carbon dioxide at 200 atm CO2 containing 10 atm H2 and 80 °C in 1 h. Diphenyl ether was the major product of Pd/Al. Rh/Al and Rh-Pd/Al further hydrogenated two benzene rings of diphenyl ether to form dicyclohexyl ether. The hydrogenolysis of CO bonds on diphenyl ether over Rh/Al and Rh-Pd/Al was observed to generate cyclohexanol and cyclohexane (<1%). With respect to hydrodebromination efficiency and catalyst stability, Rh-Pd/Al among three catalysts is suggested to be used for ex situ degradation of polybrominated diphenyl ethers in supercritical carbon dioxide.
authors.affiliation: Department of Chemistry, National Dong-Hwa University, Hualien, 32023, Taiwan, ROC.
authors.forename: Ben-Zen
authors.initials: BZ
authors.lastname: Wu
authors.affiliation: Department of Chemistry, National Dong-Hwa University, Hualien, 32023, Taiwan, ROC.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Sun
authors.affiliation: Department of Chemistry, National Dong-Hwa University, Hualien, 32023, Taiwan, ROC.
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Department of Chemistry, Chung Yuan Christian University, ChungLi, 97401, Taiwan, ROC.
authors.forename: Hwa Kwang
authors.initials: HK
authors.lastname: Yak
authors.affiliation: Department of Environmental Engineering and Science, Feng Chia University, Taichung, 40724, Taiwan, ROC.
authors.forename: Jya-Jyun
authors.initials: JJ
authors.lastname: Yu
authors.affiliation: Department of Chemistry, National Dong-Hwa University, Hualien, 32023, Taiwan, ROC. Electronic address: liao1427@alumni.uidaho.edu.
authors.forename: Weisheng
authors.initials: W
authors.lastname: Liao
authors.affiliation: Department of Chemistry, National Dong-Hwa University, Hualien, 32023, Taiwan, ROC. Electronic address: ckh@mail.ndhu.edu.tw.
authors.forename: KongHwa
authors.initials: K
authors.lastname: Chiu
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC.
authors.forename: Shie-Ming
authors.initials: SM
authors.lastname: Peng
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D055768:Halogenated Diphenyl Ethers / Q000032:analysis* / Q000737:chemistry; D006842:Hydrocarbons, Brominated / Q000032:analysis* / Q000737:chemistry; D006865:Hydrogenation; D053768:Metal Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D011208:Powders; D012238:Rhodium / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D055768:Halogenated Diphenyl Ethers; D006842:Hydrocarbons, Brominated; D011208:Powders; D014874:Water Pollutants, Chemical; D002245:Carbon Dioxide; D010165:Palladium; D000535:Aluminum; D012238:Rhodium
keywords: Aluminum; Nanoparticles; Polybrominated diphenyl ethers; Supercritical carbon dioxide