Volatile organic compounds（VOCs） are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use...Volatile organic compounds（VOCs） are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use of activated carbons as adsorbents and oxide-supported metals as catalysts. Notably, activated carbons easily adsorb water, which strongly hinders the adsorption of VOCs; conventional oxides typically possess relatively low surface areas and random pores, which effectively influence the catalytic conversion of VOCs. Zeolites, in contrast with activated carbons and oxides, can be designed to have very uniform and controllable micropores, in addition to tailored wettability properties, which can favor the selective adsorption of VOCs. In particular, zeolites with selective adsorptive properties when combined with catalytically active metals result in zeolite-supported metals exhibiting significantly improved performance in the catalytic combustion of VOCs compared with conventional oxide-supported catalysts. In this review, recent developments on VOC abatement by adsorptive and catalytic techniques over zeolite-based materials have been briefly summarized.展开更多
Most of volatile organic compounds （VOCs） are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalys...Most of volatile organic compounds （VOCs） are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalysts. Many catalysts including transition metal oxides, mixed metal oxides, and sup‐ported noble metals have been developed. Among these catalysts, the porous ones attract much attention. In this review, we focus on recent advances in the synthesis of ordered mesoporous and macroporous transition metal oxides, perovskites, and supported noble metal catalysts and their catalytic oxidation of VOCs. The porous catalysts outperformed their bulk counterparts. This excel‐lent catalytic performance was due to their high surface areas, high concentration of adsorbed oxy‐gen species, low temperature reducibility, strong interaction between noble metal and support and highly dispersed noble metal nanoparticles and unique porous structures. Catalytic oxidation of carbon monoxide over typical catalysts was also discussed. We made conclusive remarks and pro‐posed future work for the removal of VOCs.展开更多
The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed ...The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed （MI） and chestnut （CH）） were used. Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry （GC/MS）. Thirty-nine volatile compounds were identified in dry-cured Celta ham samples. Most abundant volatiles in ham samples were aldehydes, which represented respectively, 53% （CO）, 51% （MI） and 46% （CH） of the total volatile composition. With the exception of 2-butenal, 2-methyl, all aldehydes were affected by feeding system. On the other hand, hydrocarbons n-alkanes were the second major group in the volatile proifle of dry-cured Celta hams and represented 28.9, 35.7 and 32.4%of the total volatile composition for CO, MI and CH groups, respectively. Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the ifnishing diet of pigs. Principal component analysis showed a good separation among groups. The discriminant analysis selected eight variables （butanoic acid, hexanal, octanal, nonenal （E）, decenal （E）, tetradecane, decane trimethyl and pyridine 2-methyl） and calculated two discriminating functions to predict if chestnut has been included in the ifnishing diet. Thus, it was possible to discriminate between groups fed with ifnishing diets containing chestnuts in their composition （mixed and chestnut group）.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(2015XZZX004-04)Zhejiang Provincial Natural Science Foundation(LR15B030001)~~
文摘Volatile organic compounds（VOCs） are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use of activated carbons as adsorbents and oxide-supported metals as catalysts. Notably, activated carbons easily adsorb water, which strongly hinders the adsorption of VOCs; conventional oxides typically possess relatively low surface areas and random pores, which effectively influence the catalytic conversion of VOCs. Zeolites, in contrast with activated carbons and oxides, can be designed to have very uniform and controllable micropores, in addition to tailored wettability properties, which can favor the selective adsorption of VOCs. In particular, zeolites with selective adsorptive properties when combined with catalytically active metals result in zeolite-supported metals exhibiting significantly improved performance in the catalytic combustion of VOCs compared with conventional oxide-supported catalysts. In this review, recent developments on VOC abatement by adsorptive and catalytic techniques over zeolite-based materials have been briefly summarized.
基金supported by the National High Technology Research and Development Program (863 Program,2015AA034603)the National Natural Science Foundation of China (21377008,201077007,20973017)+1 种基金Foundation on the Creative Research Team Construction Promotion Project of Beijing Municipal InstitutionsScientific Research Base Construction-Science and Technology Creation Platform National Materials Research Base Construction~~
文摘Most of volatile organic compounds （VOCs） are harmful to the atmosphere and human health. Cata‐lytic combustion is an effective way to eliminate VOCs. The key issue is the availability of high per‐formance catalysts. Many catalysts including transition metal oxides, mixed metal oxides, and sup‐ported noble metals have been developed. Among these catalysts, the porous ones attract much attention. In this review, we focus on recent advances in the synthesis of ordered mesoporous and macroporous transition metal oxides, perovskites, and supported noble metal catalysts and their catalytic oxidation of VOCs. The porous catalysts outperformed their bulk counterparts. This excel‐lent catalytic performance was due to their high surface areas, high concentration of adsorbed oxy‐gen species, low temperature reducibility, strong interaction between noble metal and support and highly dispersed noble metal nanoparticles and unique porous structures. Catalytic oxidation of carbon monoxide over typical catalysts was also discussed. We made conclusive remarks and pro‐posed future work for the removal of VOCs.
基金financially supported by the Spanish Ministry of Science and Innovation(AGL2008-05274-C02-01/ALI)
文摘The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed （MI） and chestnut （CH）） were used. Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry （GC/MS）. Thirty-nine volatile compounds were identified in dry-cured Celta ham samples. Most abundant volatiles in ham samples were aldehydes, which represented respectively, 53% （CO）, 51% （MI） and 46% （CH） of the total volatile composition. With the exception of 2-butenal, 2-methyl, all aldehydes were affected by feeding system. On the other hand, hydrocarbons n-alkanes were the second major group in the volatile proifle of dry-cured Celta hams and represented 28.9, 35.7 and 32.4%of the total volatile composition for CO, MI and CH groups, respectively. Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the ifnishing diet of pigs. Principal component analysis showed a good separation among groups. The discriminant analysis selected eight variables （butanoic acid, hexanal, octanal, nonenal （E）, decenal （E）, tetradecane, decane trimethyl and pyridine 2-methyl） and calculated two discriminating functions to predict if chestnut has been included in the ifnishing diet. Thus, it was possible to discriminate between groups fed with ifnishing diets containing chestnuts in their composition （mixed and chestnut group）.
