Band 41, Heft 6

This review article mainly surveys our research results of biphasic catalysis with nonionic tenside ligands. Emphasis is given to the synthesis and property of cloud point of the nonionic tenside ligands, the general principles of thermoregulated phase-transfer catalysis (TRPTC) and thermoregulated phase-separable catalysis (TPSC). It also explores the applications of TRPTC and TPSC in the hydroformylation of higher olefins and CO selective reduction of nitroarenes. The introduction of TRPTC to biphasic systemis free from the shortcomings of classical aqueous/organic two-phase catalysis, in which the application scope is restrained by the water solubility of the organic substrate. The biphasic catalysis with nonionic tenside ligands was characterized by homogeneous catalysis coupled with convenient biphasic separation.

In this paper, δ layered sodium disilicate with high framework stability has been synthesized by adding the salts of divalent and trivalent elements. In these salts AlCl 3 had the best effect for leaving the phase transformation of δ-Na 2 Si 2 O 5 . XRD, SEM, Ca 2+ ion binding capacity and clean experiment were used for measuring their properties. The data proved that Al-δ-Na 2 Si 2 O 5 had good framework stability. δ phase was still major phase after Al-δ-Na 2 Si 2 O 5 was treated in hot water (80°C) for 60 minutes. And Ca 2+ ion binding capacity may keep at 305 mg CaCO 3 /g through the treatment. The cleaning experiments showed that Al-δ-Na 2 Si 2 O 5 had good washing ability.

With the focus on quaternary ammonium compounds, this paper describes how the ortho ester chemistry can be used as a versatile tool for synthesis of cleavable surfactants of various types. This class of chemodegradable surfactants hydrolyzes rapidly under mild acidic conditions at the same time as they are long-term stable in alkaline aqueous solutions. Further, the rate of cleavage can be modified by varying the structure of the surfactant. An additional feature is the possibility to design surface active compounds that release a daughter surfactant with different properties upon cleavage. Ortho ester-based surfactants could be of use in a large number of applications as exemplified in the paper. Good biodegradation data are of importance for virtually all types of surfactants nowadays. However, there actually seem to exist very few, if any, investigations regarding the biodegradation of cleavable surfactants under both hydrolytical and non-hydrolytical conditions. Data from the initial part of such a study on cationic ortho ester surfactants are presented and discussed in this paper. The results strongly indicate rapid biodegradation for this class of compounds under varying conditions.

The modern societies are not any more ready to accept malodors as an inevitable fact but they tend to control osmogens and spread good smells. Hereby the use of zinc ricinoleate has grown to a common system for odor control in recent years. Theoretical description of odor absorbing mechanism was done recently. For performance evaluation of these malodor absorbing systems a new analytical method, the solid phase micro-extraction (SPME), is now available. With this knowledge, the next task is to develop a malodor absorber system with required efficacy.

The enzymatic synthesis of fatty acid ester based care specialties is a prime example of a modern, innovative and sustainable technology. This article gives an overview on the advantages of this process compared to traditional production methods. Economic as well as quality aspects will be discussed, furthermore, an example of a novel product that is only available by this biocatalytical method will be given.

Though oxygen demands are critical measurements for waste water treatment plant operation and water quality management, they are of little relevance to assess or rank the environmental quality of detergents. It is argued that: (1) No accurate measurements of the oxygen demand of bleach detergents can be made, because these products release oxygen during the measurement. (2) When waste water is adequately treated, under normal operating conditions the oxygen demand (organic loading) of the raw sewage has no influence on river quality. (3) Oxygen demand values are narrowly focused on environmental exposure, while they do not take into account the potential for ecotoxicological effects. (4) Short-term biological oxygen demand measurements are useful for the monitoring of ‘average sewage', but they are unreliable to assess the biodegradability of more specific substances or products. Instead of oxygen demands, more holistic evaluations based on risk assessment or on life cycle analysis are scientifically preferred.

The 30 th anniversary of the GDCh-Fachgruppe Waschmittelchemie (Expert Group Detergent Chemistry) was celebrated at this year's Conference in Königswinter. Unfortunately, only some 80 people attended this fine meeting that was focused on Ecology/Toxicology but also encompassed stimulating papers in Basics/Mechanisms, Raw Materials/Syntheses , and Applications . 19 lectures and 13 posters were given. The anniversary marked the end of the conference in this form because the annual meeting of the Expert Group will be developed to a European Detergents Conference (EDC) that will be embedded in the next SEPAWA Kongress 2005 for the first time. At the anniversary's celebratory convention D. Schermer , Chairman of the Expert Group, reviewed the activities of the Expert Group, which was founded in 1974 in Bamberg to meet the need of scientifically based open discussions on ecological issues of detergent chemistry. In the meantime, the Group has been developed into an active forum for scientific exchange in all fields of detergent chemistry. Furthermore, it has contributed to the practicable solution of many environmental problems and to a more serious public discussion about surfactants and detergents. Many problems remain to be solved, and therefore an active cooperation also with other expert groups of the German Chemical Society (GDCh) is crucial. In his celebrating address W. Koch , General Manager of the GDCh, stressed that in its early days the Group had implemented consumer and environmental protection in its catalogue of topics. In so far, the today's motto “From an isolated problem solving to a sustainable responsibility” is just a consequent extension of its activities. He also asked all members to strive for new members of the GDCh to strengthen this scientific society as one of the largest in Europe. In his celebratory lecture D. Ruchay , Monheim, Germany, summarized “30 Years of Water Protection in Germany – Through Societal Cooperation to Success”. After World War Two there were no municipal and industrial sewage plants in Germany able to work. The infrastructure of waste water management was built up very slowly in the first 20 years after the war. Correspondingly the quality of the inshore waters impaired dramatically. Since 1970 the water quality improved significantly. At that time the water management act had been tightened considerably and the waste water fee depending on the quality and pollution of the waste water was established. Today the water quality in the German inshore waters is fair up to good, but the ecological situation has still to be improved. For some years the water regulations are laid down decisively by the European Union (The Water Framework Directive, The Urban Waste-water Treatment Directive, The Integrated Pollution Prevention Control Directive).