Wasserabsorptionseigenschaften natürlicher polyionenkomplexe

As the cationic component of natural polymer polyionic complexes, polysaccharide chitosan or polypeptide polylysine, and as the anionic component, polysaccharide carboxymethyl cellulose (=CMC) or polypeptide poly(glutamic acid) (PGA) were used. The degree of chitosan/CMC or polylysine/PGA complex film swelling was minimum, when the amounts of the cationic and anionic groups in these polymers were balanced at 1 : 1 ratio. On the other hand, the degree of chitosan/PGA film swelling was minimum at the ratio with excess of PGA which is a linear flexible chain. Comparing the enthalpies estimated by DSC analysis, it was suggested that the larger quantity of water in the form of nonfreezable bound water was absorbed in the complex films with polysaccharide which is a chain of ring structure. Further, the compressive moduli of swollen complex films were high, when the complex consisted of polysaccharide components.     

Scale‐up und detaillierte Prozessanalyse eines Membranreaktors am Beispiel einer heterogen katalysierten Veresterung

The combination between reaction and pervaporation has been investigated using the example of a heterogeneous catalysed esterification reaction. The process model parameters have been determined based on experimental investigations and a scale‐up has been performed to the pilot scale. A detailed process analysis leads to optimal operating as well as structural variables and two separation sequences have been suggested.     

Optimale Gestaltung großtechnischer Anlagen zur Geradeausdestillation natürlicher Fettsäuren

Optimum Layout of Technical Plants for Straight Distillation of Natural Fatty Acids The present study is concerned with the suitable layout and construction of individual elements and costs of plant operation for straight distillation of fatty acids with respect to increasing cost of energy and quality improvement by mild treatment of fatty acids, especially those containing double bonds, which are sensitive to heat and oxidation. The principle of distillation, developed by the author, involves the processing for such a sensitive system in three different parts of the plant: Preliminary degassing, dehydration and deodorization, the main distillation and subsequent separation of pitch. Aspects considered are environmental safety, influence of heating, residence time, leaks and corrosion.     

Polytrope Kinetikmessung zur Bewertung von Ionenaustauscherharzen für die Veresterung von Acrylsäure mit n‐Butanol

A catalyst screening for the esterification of acrylic acid with n‐butanol is presented. The kinetics was investigated in the temperature range of 70 – 100 °C and the selectivity was determined. The kinetic data fitted well with the Langmuir‐Hinshelwood‐Hougen‐Watson approach. The model was applied for the design of a reactive distillation column. Due to the similar fluid dynamics and the fast data generation a temperature scanning plug flow reactor was used.     

Über ein neues Verfahren zur kontinuierlichen Entsäuerung natürlicher Speiseöle und Fette durch Extraktion mit verdünnter Alkalilauge

A New Process for the Continuous Deacidification of Edible Oils and Fats by Extraction with Dilute Alkali Solution The known technical process for the deacidification of natural oils and fats, and hardened fats, using dilute alkali in batch operation is associated with certain difficulties. Ziehl's extraction column provided with moving elements permits a continuous operation of the aforesaid process with short hold-up time, low space requirement and considerably less saponification loss. The different operations involved, e. g. deacidification, washing with salt solution and with water, are carried out in the same unit.     

HF-unterstützte Synthese von Orthoestern und Oxazolinen. [1]

A convenient method is reported to generate the ortho-pivalic acid esters 5 and 7 from meso-erythrit 3 ) and D -mannitol ( 6 ), respectively, using a HF-supported procedure. Furthermore, the α-D -glucopyrano[1,2-d]-2-oxazolines 9 and 10 were prepared from starch and nitriles (pivalonitrile and benzonitrile) by a Ritter-type reaction in anhydrous hydrogen fluoride. The separation of the products 5 , 7 , 9 , and 10 was possible by quenching of their HF-solutions with triethylamine. The structure of the orthoester 7 and the oxazoline 10 was confirmed by X-ray analyses.