The adsorption characteristics of Zn2+ from electrolytic solution by activatedcharcoal have been investigated. It was found that the amount of adsorption of Zn2+depends mainly on pH value of the solution, added inorga...The adsorption characteristics of Zn2+ from electrolytic solution by activatedcharcoal have been investigated. It was found that the amount of adsorption of Zn2+depends mainly on pH value of the solution, added inorganic ions and containing Oxygen groups on the surface. The activated charcoal was treated with oaldation-negativeionizing (OA) method in order to produce more containing oxygen groups on the surface.The adsorption amount of Zn2+ on the treated activated charcoal increased remarkbly. Itwas also found that the more times the activated charcoal was treated, the moe powerfulthe acidity of the surface, and the larger the adsorption amoUn of Zn2+, so the chargedgrorps on the surface of activated charcoal are considered as the main adsorption activatedsites for inorganic ions. The adsorption characteristics of various complexes of Zn2+ onthe surface of activated charcoal have also been investigated. Three types of adsorptionnconfiguration of the complexes of Zn2+ on the surface of activated charcoal were suggestedaccording to the experimental results.展开更多
Co3O4 catalysts prepared with different precipitants（NH3·H2O,KOH,NH4HCO3,K2CO3 and KHCO3）were investigated for the oxidation of formaldehyde（HCHO）.Among these,KHCO3-precipitated Co3O4（KHCO3-Co） was the most...Co3O4 catalysts prepared with different precipitants（NH3·H2O,KOH,NH4HCO3,K2CO3 and KHCO3）were investigated for the oxidation of formaldehyde（HCHO）.Among these,KHCO3-precipitated Co3O4（KHCO3-Co） was the most active low-temperature catalyst,and was able to completely oxidize HCHO at the 100-ppm level to CO2 at 90℃.In situ diffuse reflectance infrared spectroscopy demonstrated that hydroxyl groups on the catalyst surface were regenerated by K~＋ and CO3^（2-）,thus promoting the oxidation of HCHO.Moreover,H2-temperature programmed reduction and X-ray photoelectron spectroscopy showed that employing KHCO3 as the precipitant increased the Co^3＋/Co^2＋molar ratio on the surface of the Co3O4 catalyst,thus further promoting oxidation.Structural characterization revealed that catalysts precipitated with carbonate or bicarbonate reagents exhibited greater specific surface areas and pore volumes.Overall,these data suggest that the high activity observed during the Co3O4 catalyzed oxidation of HCHO can be primarily attributed to the presence of K~＋ and CO3^（2-） on the Co3O4 surface and the favorable Co^3＋/Co^2＋ ratio.展开更多
文摘The adsorption characteristics of Zn2+ from electrolytic solution by activatedcharcoal have been investigated. It was found that the amount of adsorption of Zn2+depends mainly on pH value of the solution, added inorganic ions and containing Oxygen groups on the surface. The activated charcoal was treated with oaldation-negativeionizing (OA) method in order to produce more containing oxygen groups on the surface.The adsorption amount of Zn2+ on the treated activated charcoal increased remarkbly. Itwas also found that the more times the activated charcoal was treated, the moe powerfulthe acidity of the surface, and the larger the adsorption amoUn of Zn2+, so the chargedgrorps on the surface of activated charcoal are considered as the main adsorption activatedsites for inorganic ions. The adsorption characteristics of various complexes of Zn2+ onthe surface of activated charcoal have also been investigated. Three types of adsorptionnconfiguration of the complexes of Zn2+ on the surface of activated charcoal were suggestedaccording to the experimental results.
基金supported by the National Natural Science Foundation of China(21577088)~~
文摘Co3O4 catalysts prepared with different precipitants（NH3·H2O,KOH,NH4HCO3,K2CO3 and KHCO3）were investigated for the oxidation of formaldehyde（HCHO）.Among these,KHCO3-precipitated Co3O4（KHCO3-Co） was the most active low-temperature catalyst,and was able to completely oxidize HCHO at the 100-ppm level to CO2 at 90℃.In situ diffuse reflectance infrared spectroscopy demonstrated that hydroxyl groups on the catalyst surface were regenerated by K~＋ and CO3^（2-）,thus promoting the oxidation of HCHO.Moreover,H2-temperature programmed reduction and X-ray photoelectron spectroscopy showed that employing KHCO3 as the precipitant increased the Co^3＋/Co^2＋molar ratio on the surface of the Co3O4 catalyst,thus further promoting oxidation.Structural characterization revealed that catalysts precipitated with carbonate or bicarbonate reagents exhibited greater specific surface areas and pore volumes.Overall,these data suggest that the high activity observed during the Co3O4 catalyzed oxidation of HCHO can be primarily attributed to the presence of K~＋ and CO3^（2-） on the Co3O4 surface and the favorable Co^3＋/Co^2＋ ratio.
