A new adsorbent for heavy metal ions, sulfhydryl chitosan (S chitosan), was produced by treatment of chitosan with sulhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confirmed by e...A new adsorbent for heavy metal ions, sulfhydryl chitosan (S chitosan), was produced by treatment of chitosan with sulhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confirmed by elemental analysis and FT IR spectra analysis. The adsorption properties of sulfhydryl chitosan for Cu(Ⅱ), Cd(Ⅱ), Pb(Ⅱ), Cr(Ⅲ) and Ni(Ⅱ) were investigated, and the effect of pH value on adsorption, adsorption kinetics, and selective adsorption was examined. It was shown that S chitosan has good adsorption for Pb(Ⅱ), Cu(Ⅱ) and Cd(Ⅱ) like chitosan, is also insoluble in acid solution; has good adsorption kinetic properties for heavy metal ions; and can be used in acid solution. The adsorption capacities of S chitosan can be affected by media acidity. The adsorbed Cu(Ⅱ) Cd(Ⅱ)and Pb(Ⅱ) could be eluted by diluted chlorhydric acid.展开更多
The centralized processing of high-sulfur and high-acidity crude has contributed to improvement of the overall economic benefits of the oil refining enterprise, but has also resulted in crude emulsification, severe co...The centralized processing of high-sulfur and high-acidity crude has contributed to improvement of the overall economic benefits of the oil refining enterprise, but has also resulted in crude emulsification, severe corrosion of process units and environmental protection issues. The long-cycle, safe and smooth operation of process units were guaranteed after selection of optimal processing routes and adoption of a series of technical measures.展开更多
The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, i...The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, it must be treated by the application of physicochemical or biological methods with the ability to separate high contents in sulfates, hydrogen sulphite and sulphides which have laxative, allergic and toxic properties in humans. Conventional methods require the supply of chemical compounds or the adequate control of different parameters such as pH, temperature, etc., and the constant maintenance within their reactors. For these reasons, the systems could have elevated operating costs and require additional steps to enable the treatment of its separated products and the final disposal of its residual waste generated. In this research, compound parabolic collectors are implemented for the use of solar energy radiation, UV-B type, in Solar Advanced Oxidation Processes in H2O2/O3/UVsolar homogeneous phase. Its application during the pre-treatment of four sulfur water wells from the region of Puebla, Mexico, demonstrated its ability to transform their sulfur compounds in sulfates of easy removal by a later stage of reverse osmosis, in an approximately 15 min treatment time process.展开更多
文摘A new adsorbent for heavy metal ions, sulfhydryl chitosan (S chitosan), was produced by treatment of chitosan with sulhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confirmed by elemental analysis and FT IR spectra analysis. The adsorption properties of sulfhydryl chitosan for Cu(Ⅱ), Cd(Ⅱ), Pb(Ⅱ), Cr(Ⅲ) and Ni(Ⅱ) were investigated, and the effect of pH value on adsorption, adsorption kinetics, and selective adsorption was examined. It was shown that S chitosan has good adsorption for Pb(Ⅱ), Cu(Ⅱ) and Cd(Ⅱ) like chitosan, is also insoluble in acid solution; has good adsorption kinetic properties for heavy metal ions; and can be used in acid solution. The adsorption capacities of S chitosan can be affected by media acidity. The adsorbed Cu(Ⅱ) Cd(Ⅱ)and Pb(Ⅱ) could be eluted by diluted chlorhydric acid.
文摘The centralized processing of high-sulfur and high-acidity crude has contributed to improvement of the overall economic benefits of the oil refining enterprise, but has also resulted in crude emulsification, severe corrosion of process units and environmental protection issues. The long-cycle, safe and smooth operation of process units were guaranteed after selection of optimal processing routes and adoption of a series of technical measures.
文摘The sulfurous water deposit exploitation in volcanic, swamp, or wetland regions, represents an alternative option for potable water supply in cities and communities around the world. However, before its consumption, it must be treated by the application of physicochemical or biological methods with the ability to separate high contents in sulfates, hydrogen sulphite and sulphides which have laxative, allergic and toxic properties in humans. Conventional methods require the supply of chemical compounds or the adequate control of different parameters such as pH, temperature, etc., and the constant maintenance within their reactors. For these reasons, the systems could have elevated operating costs and require additional steps to enable the treatment of its separated products and the final disposal of its residual waste generated. In this research, compound parabolic collectors are implemented for the use of solar energy radiation, UV-B type, in Solar Advanced Oxidation Processes in H2O2/O3/UVsolar homogeneous phase. Its application during the pre-treatment of four sulfur water wells from the region of Puebla, Mexico, demonstrated its ability to transform their sulfur compounds in sulfates of easy removal by a later stage of reverse osmosis, in an approximately 15 min treatment time process.
