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Plasmonic nanoparticles exhibit excellent light-harvesting properties in the visible spectral range, which makes them a convenient material for the conversion of light into useful chemical fuel. However, the need for using surface ligands to ensure colloidal stability of nanoparticles inhibits their photochemical performance due to the insulating molecular shell hindering the carrier transport. We show that cellulose fibers, abundant in chemical functional groups, can serve as a robust substrate for the immobilization of gold nanorods, thus also providing a facile way to remove the surfactant molecules. The resulting functional composite was implemented in a bioinspired photocatalytic process involving dehydrogenation of sodium formate and simultaneous photoregeneration of cofactor molecules (NADH, nicotinamide adenine dinucleotide) using visible light as an energy source. By systematic screening of experimental parameters, we compare photocatalytic and thermocatalytic properties of the composite and evaluate the role of palladium cocatalyst.

Time-resolved investigations using in situ energy-dispersive X-ray diffraction in tandem with ex situscanning electron microscopy revealed that solvothermal crystallisation of ZIF-8 in methanol solvent and in the presence of sodium formate as a simple monodentate ligand (modulator) is a rapid process yielding big, high-quality single crystals in short time (<4 h). Kinetic analysis of crystallisation curves was performed by applying the Avrami–Erofe'ev and Gualtieri models. The analyses revealed that the weakly basic formate modulator acts as a base in deprotonation equilibria (deprotonation of the bridging 2-methylimidazole ligand) rather than as a competitive ligand in coordination equilibria at the metal (Zn2+) centres. This is in contrast to the coordination modulation function of formate in ZIF-8 synthesis at room temperature. Crystal shape evolves with time in the presence of formate from cubes with truncated edges to rhombic dodecahedra. The latter shape represents most likely the stable equilibrium morphology of ZIF-8.

In de periode van 9 oktober tot en met 6 november 2001 is op rwzi De Drie Ambachten bij wijze van proef natriumformiaat gedoseerd als externe koolstofbron. Dit ter verbetering van de denitrificatie. Doel van de proef was na te gaan of natriumformiaat proces- en kostentechnisch bruikbaar is als alternatief voor methanol

In aquous solutions CO2 and bicarbonate react with negatively charged polarons (H2O)- formed by the irradiation of water by gamma-rays, leading to formation of the carboxyl radical ion. In the presence of organic solutes, the carboxyl radical ion may add on to other free radicals, e.g. those formed by the action of radiation produced OH radicals on organic solutes, to give the corresponding carboxylic acids. Using C-14 labelled carbon dioxide or bicarbonate, this process could provide a method for the production of carboxylic acids labelled in the carboxyl group. In neutral solutions two reducing species, i.e. negative polarons and primarily formed H atoms, have been shown to be present in irradiated water; their reactions with various solutes have been studied. All irradiations were carried out with Co-60 gamma rays. For irradiation of aqueous solutions in the presence and absence of different gases (O2, CO2, N2O) standard irradiation techniques were used. Analysis of the gaseous irradiation products was carried out by means of the mass-spectrometer. Other irradiation products were determined spectrophotometrically or by radioactive tracer techniques.

This paper presented a method of preferential complexing-hydrolysis precipitation to separate ferrochrome and reduce the loss of Cr while removing Fe, in order to address the separation problem of Fe and Cr in the sulphuric acid leaching solution of an electroplating sludge. The complexing mechanism of sodium formate with ferric sulphate, chromium sulphate, and a mixed solution of ferric sulphate and chromium sulphate, was studied comprehensively by UV spectrophotometry and mass spectrometry. The results show that both chromium and ferric ions can form complexes with sodium formate but that under the same conditions, the complexing of Fe3+ and sodium formate in aqueous solution is prior to that of Cr3+. The calculation of reaction heat effect shows that these reactions are endothermic and the high temperature is favourable especially for ferric reactions rather than chromium. The effects of amount of sodium formate, reaction temperature and holding time on the separation efficiency between iron and chromium were studied. The results show that when the molar ratio of HCOO-/Cr3+ is 5.5, reaction temperature is 90 degrees C, holding time is 6 h, the pH value of the solution is adjusted to 2.5 with addition of alkali and the reaction time is 30 min, the Fe precipitation rate is 93.65% and the Cr precipitation rate only 13.37%. The separation effect of Cr3+ and Fe3+ is good., This paper presented a method of preferential complexing-hydrolysis precipitation to separate ferrochrome and reduce the loss of Cr while removing Fe, in order to address the separation problem of Fe and Cr in the sulphuric acid leaching solution of an electroplating sludge. The complexing mechanism of sodium formate with ferric sulphate, chromium sulphate, and a mixed solution of ferric sulphate and chromium sulphate, was studied comprehensively by UV spectrophotometry and mass spectrometry. The results show that both chromium and ferric ions can form complexes with sodium formate but that under the same conditions, the complexing of Fe3+ and sodium formate in aqueous solution is prior to that of Cr3+. The calculation of reaction heat effect shows that these reactions are endothermic and the high temperature is favourable especially for ferric reactions rather than chromium. The effects of amount of sodium formate, reaction temperature and holding time on the separation efficiency between iron and chromium were studied. The results show that when the molar ratio of HCOO-/Cr3+ is 5.5, reaction temperature is 90 degrees C, holding time is 6 h, the pH value of the solution is adjusted to 2.5 with addition of alkali and the reaction time is 30 min, the Fe precipitation rate is 93.65% and the Cr precipitation rate only 13.37%. The separation effect of Cr3+ and Fe3+ is good.

Goethite, a typical iron-containing monomineral in red mud, was synthesised under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium formate, sodium acetate, sodium oxalate, sodium salicylate and disodium phthalate on the settling performance of goethite slurries were studied. The settling performance of the slurries was also investigated with the addition of self-made hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of dissolved organic compounds on the goethite surfaces was studied by FT-IR and XPS, respectively. The results show that the addition of organic compounds lowers the settling performance of the slurries and a deterioration in settling performance is observed in the order of sodium oxalate before sodium salicylate and disodium phthalate, sodium formate and lastly sodium acetate. Moreover, HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the goethite slurries, but it can only partially improve the settling performance of the goethite slurries containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that these organic compounds are chemically adsorbed on the goethite surface., Goethite, a typical iron-containing monomineral in red mud, was synthesised under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium formate, sodium acetate, sodium oxalate, sodium salicylate and disodium phthalate on the settling performance of goethite slurries were studied. The settling performance of the slurries was also investigated with the addition of self-made hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of dissolved organic compounds on the goethite surfaces was studied by FT-IR and XPS, respectively. The results show that the addition of organic compounds lowers the settling performance of the slurries and a deterioration in settling performance is observed in the order of sodium oxalate before sodium salicylate and disodium phthalate, sodium formate and lastly sodium acetate. Moreover, HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the goethite slurries, but it can only partially improve the settling performance of the goethite slurries containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that these organic compounds are chemically adsorbed on the goethite surface.