Hydrotrope Substanzen für die Herstellung flüssiger Waschmittel

Hydrotropic Substances for the Preparation of Liquid Washing Agents The hydrotropic action of short chain alkyl benzenesulfonates was investigated on anion active and non-ionic raw materials for detergents as well as on their combinations containing either or no inorganic salts. In the combinations studied it was found that alkali salts of cumol sulfonate were the best hydrotropic agents. The solubility of the raw materials for washing agents could be improved such that concentrated charges with satisfactory clear-melting point could be prepared. The salting out effect of inorganic salts on aqueous solutions of raw materials for detergents is prevented by alkali-cumol sulfonate.     

Hydrierung von p‐Nitrophenol zu p‐Aminophenol als Testreaktion für die katalytische Aktivität von Pt‐Trägerkatalysatoren

The hydrogenation of p‐nitrophenol (PNP) to p‐aminophenol (PAP) using NaBH₄ as a reducing agent was studied as a test reaction for determining the catalytic activity of supported Pt catalysts. The initial reaction rate, which is accessible within less than 10 minutes via online UV‐vis spectroscopy at room temperature, ambient pressure and in water as a solvent, was used as measure for the catalytic activity. For three Pt catalysts supported on porous SiO₂, porous glass and Al₂O₃, respectively, significant differences in the catalytic activity were observed. However, especially in case of very active catalysts, limitations of the reaction by internal or external mass transfer have to be considered.     

Wachse mit hoher Dispergierfähigkeit unter besonderer Berücksichtigung ihrer Eignung für die Herstellung von Kohlepapierfarbmassen

Waxes Having High Dispersibility and Special Consideration of Their Suitability in the Manufacture of Colouring Masses for Carbon Paper Increasing amounts of waxes having fundamentally different chemical composition are being used as dispersion aids. In the manufacture of colouring masses for carbon papers, the materials used as vehicle of the colour and as dispersing agent for carbon black are hydrocarbons, wax acids and their natural esters. Whereas low-priced paraffins are mainly used for cheap carbon papers meant for a single use, carnauba wax is used for better quality carbon papers which can be used several times. The latter wax is especially suited because of its carbon black-dispersing and oil-binding properties. Since crude montana wax does not have these properties to such an extent as the carnauba wax, it was attempted to improve the carbon black-dispersing and oil-binding of montana wax by chemical synthesis. This was achieved by reacting crude montana wax with maleic anhydride and subsequent esterification of the reaction products with glycols. The results were successfully applied to the solution of problems involving dispersion of pigments and plastic additives.     

Eine Studie über den Pyrolysevorgang bei organischen Bindemittelsubstanzen für die Herstellung von Kohlenstoffmaterialien

Pyrolysis behaviour and coke characteristics of different precursors for carbon processing: thermosetting resins (resol, novolak), hydrolytic lignin, pitch, tar as well as their blends were studied using differential thermal analysis (DTA) and X-ray diffraction techniques. The blends novolak-pitch, resol-tar and resol-hydrolytic lignin show a higher coke yield after carbonisation up to 1000°C compared to the corresponding individual substances. A good correlation between the integral procedural decomposition temperature T of the investigated precursors and their coke yield is found.