To promote biobased products for the industry, six biosurfactants isolated from green and food urban residues aged under aerobic digestion for 0−60 days were investigated for their potential to perform as auxiliaries for dyeing cellulose acetate fabric with water-insoluble dyes. The experimental plan included investigation of the chemical nature, surface activity, and power to enhance dye solubility in water, as well as dyeing test performed under a variety of experimental conditions presenting a range of challenge levels. For comparison, the same investigation was performed on commercial synthetic surfactants. The investigated biosurfactants exhibited chemical composition and surface activity properties presumably related to their different biomass sources. However, no significant performance differences in textile dyeing were evident among the biosurfactants and between biosurfactants and synthetic surfactants. The results encourage product and process development for exploitation of biomass residues as a source of chemicals to recycle to the industry.

A major application of polyfunctional acid materials is the fabrication of solid electrolytes exhibiting proton conductivity in the solid state for operation in fuel cells at medium temperature (<160°C). Because the advancement of research on solid proton conductors depends on the availability of new precursors, a new acid organosulphur phosphorus compound, i.e., the hydrated 4-sulfophenylphosphonic acid H 2 O 3 -PC 6 H 4 SO 3 H 2 ‚2 H 2 O (IA), has been synthesized by the Tavs reaction starting from the 4-bromo(diethyl)-sulfonate precursor. This synthetic route is opposite that reported for the synthesis of many other aromatic sulfophosphonic acids, which are obtained by sulfonation of the aromatic phosphonic acid precursor. The reason for the different synthetic route in the former case lies in the fact that sulfonation of benzenephosphonic acid yields only metasubstituted derivatives. Investigation of the solid-state structure at variable temperature indicates that IA yields the anhydrous compound H 2 O 3 PC 6 H 4 SO 3 H 2 (IB) at 190-210°C. Solid state 13 C and 31 P NMR data and FT-IR measurements are consistent with intermolecular H-bonding between the sulfonic and phosphonic acid groups, and/or protonation of the phosphonic acid by the sulfonic acid group, depending on the presence of water. Ar-These interactions are very important in determining proton conductivity in relation to the possible use of IA as solid electrolyte component in fuel cells operating at medium temperature. On this basis, 4-sulfophenylphosphonic acid seems an interesting precursor for the fabrication of solid proton conducting electrolytes.

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Milled southern pine wood was modified with sequential treatments of sodium periodate and sodium hypobromite for the purpose of improving copper ion (Cu2+) sorption capacity of the wood when tested in 24-h equilibrium batch tests. The modified wood provided additional carboxyl groups to those in the native wood and substantially increased Cu2+ uptake over that of unmodified wood. Sorption capacity (qe) measured with an unbuffered standard solution increased to a maximum of 7.8 mg Cu2+ ion per gram of wood (treated) from 3.1 mg Cu2+ ion/g wood (untreated). Samples tested were first sodium ion exchanged to keep the pH of the standard solution from declining during the sorption test. The treatment necessary for maximum qe was 3% (w/v) periodate for 24 h and 0.8% (w/v) bromine (as hypobromite) for 24 h; both treatments were at room temperature. These conditions corresponded to the maximum periodate concentration and treatment times tested. To further evaluate the efficacy of modification treatments, weight change after each treatment was determined. Weight loss after the periodate stage for any concentration and time used was minor, indicating the selective nature of this reaction. However, most of the weight loss was incurred after hypobromite treatment. Weight loss corresponding to the greatest increase in sorption capacity was 12.6% total from the combined periodate and hypobromite stages. The increase of carboxylate functional groups in the wood was monitored using FTIR/ATR spectroscopy.