In this paper, the synthesis, characterization and application of a copolymer as a sizing agent obtained by the grafting of methacrylic acid on hydrolyzed potato starch were investigated. Starch hydrolysis was performed in order to reduce the average molar mass (i.e. the size of the macromolecules). Grafting of methacrylic acid on hydrolyzed potato starch was performed to obtain a product that can be effective in textile processing, for example, for sizing yarn. The grafting of the monomer has been confirmed by Fourier transform infrared spectroscopy spectra of hydrolyzed and grafted potato starch. The distribution of molar masses was determined chromatographically. The results obtained by sizing of cotton yarn with the new starch agent confirmed its higher breaking strength, elongation, abrasion resistance, reduced hairiness, better evenness, etc. Grafted hydrolyzed potato starch (almost identical to the commercial medium) exhibits better performance as a potential agent for sizing cotton yarn than ungrafted hydrolyzed starch.
A media consisting of isatin-Schiff bases (isatin-3-thiosemicarbazone, isatin-3-semicarbazone, and isatin-3-phenylhydrazone) was developed to maximize the production of antibiotics Hexaene H-85 and Azalomycine B by Streptomyces hygroscopicus. The media isatin-3-thiosemicarbazone resulted in the maximum antibiotics concentration of 372 μg cm−3 for Hexaene H-85 and 118 μg cm−3 for Azalomycine B. The impact of modified media on soil morphology also was investigated.
1 January 2019 in Chemical Industry and Chemical Engineering Quarterly
Water pollution has already become a significant worldwide problem, especially in the textile dyeing industry. This paper describes decolorization of dye water modelled by textile dye wastewater. Decolorization was performed on an adsorbent made from physicochemically modified waste hemp fibers, obtained as a by-product from the production of ropes. The adsorbent is relatively dispersive and contains heterogeneous porous particles, with carbon as a dominant element. Obtained results have shown that the positive effect of adsorption directly depends on contact time, pH, temperature, and initial dye concentration. Dye concentration decreases in time, especially when the used concentration is the initial one. The effect of temperature below 40 ?C is not significant, but adsorption gets more intensive when performed at 60 ?C. The higher degree of decolorization is achieved at lower initial dye concentrations, although the highest initial dye concentration leads to higher dye adsorption. The experimental results of adsorption were described by using the Langmuir model. The maximum adsorption capacity ranges from 1.98 to 2.13 mg g-1 for linear and 2.03 to 2.12 mg g-1 for nonlinear form.