Polyelectrolytes with sulfonic acid groups useful in the synthesis and stabilization of Au and Ag nanoparticles

Au doped metal organic frameworks as di-functional photocatalysts for clearing organics in wastewater

Along with the development of productive forces, the use of organic compounds including diversified dyes and multiple drugs has become more and more commonly, resulting in the accelerating water contamination. Herein in this paper, Au doped PCN 224 are designed as bi-functional wastewater treatment agents to absorb and decompose organics molecules efficiently under light irradiation. After inserted with Au, the PCN 224 nanoparticles, which is kind of porous, stable and photosensitive metal-organic framework, show enhanced photodegradeability. Because the Au inserted could inhibit the re-combination of electrons and holes by absorbing photo-electrons; decrease the nanoparticles' band gap, and finally produce much more free radicals. In the meanwhile, due to the lower binding energy between S and Au, the Au modified PCN 224 perform better in absorbing organic compounds consisted of S contained heterocyclic ring (such as methylene blue). This work provides new insights into the precious design of materials in clearing organic compounds.

Binding of Cobaltocenium-containing Polyelectrolytes with Anionic Probes

Cationic cobaltocenium-containing polyelectrolytes have a unique ability to form ionic complex with various anionic species. We carried out two sets of model study to compare the relative binding strength of a cobaltocenium-containing polyelectrolyte. First, the nature and relative strength of intermolecular interaction between cobaltocenium-containing polyelectrolytes and different anionic probes were investigated by spectroscopic methods. A dye-displacement method was used to monitor absorbance and fluorescence emissions. Second, the binding strength of this cobaltocenium-containing polyelectrolyte was compared with a classical quaternary ammonium polymer. Formation of polyelectrolyte complex between the cobaltocenium-containing polyelectrolyte and a common anionic polyelectrolyte at various concentrations was examined by optical absorption and light scattering.

Removal of textile dyes and metallic ions using polyelectrolytes and macroelectrolytes containing sulfonic acid groups

This work reports the removal of textile dyes and metallic ions by means of adsorption and coagulation-flocculation using two polyelectrolytes and two macroelectrolytes containing sulfonic acid groups. The adsorption of textile dyes was studied in aqueous solutions containing cationic dyes and in wastewater containing a vat dye. Also, removal of vat and naphthol dyes was studied using the process of coagulation-flocculation. The results show these materials possess elevated adsorption capacity, and they accomplished removal rates above 97% in aqueous solutions. The removal of the vat dye improved the quality of the wastewater notably, and an uncolored effluent was obtained at the end of the treatment. The treatment using adsorption decreased the values for coloration, conductivity, suspended solids, and pH. The removal of vat and naphthol dyes by means of coagulation-flocculation was studied as well, and removal rates of 90% were obtained. The polyelectrolytes and macroelectrolytes also proved effective in the adsorption of metallic ions in wastewater. The treatment using adsorption accomplished high removal rates of metallic ions, and it showed greater selectivity towards Cu(2+), Fe(3+) and Pb(2+). A decrease in the content of solids as well as the values for COD and conductivity was observed in the wastewater as well. The analyses of FT-IR indicated that cationic dyes and metallic ions were chemisorbed by means of ionic exchange.