Hydrothermal degradation of adsorbed sulfur mustard on activated carbon

Thermal and hydrothermal degradations of adsorbed sulfur mustard (HD) on activated carbon particles from a chemical protective over-garment were studied. Carbon loaded with 5 wt.% HD was heated in a closed reactor at temperatures up to 160 °C for 0.5–6 h and analyzed by solid-state ¹³C MAS NMR. On dry carbon at room temperature, HD was stable for months. On a thoroughly pre-wetted carbon, adsorbed HD partially degraded to thiodiglycol (TDG) and TDG-sulfoxide (TDG-SO) within 2–3 months. Heating dry HD-loaded carbon to 160 °C caused partial degradation within 4 h to 1,4-thioxane, along with 1,4-dithiane and vinyl sulfides. Complete degradation within 2.5 h to the same products occurred upon hydrothermal treatment of the HD-loaded carbon, using a water/carbon ratio of 0.3:1. With higher water/carbon ratios of 0.6:1–5:1 at temperatures of 120 °C and above, adsorbed HD hydrolyzed rapidly within 0.5 h. The latter reaction led to the formation of TDG concurrent with either thioxane (at 160 °C) or TDG-SO and TDG-dimer (at 120 °C). The mechanisms of the observed degradation processes are discussed.     

Entwicklung einer leistungsstarken Mikrorektifikationsapparatur für analytische und präparative Anwendungen

In this contribution it is reported about the realization of efficient micro rectification equipment (MRA), which can be operated intermittently or continuously and be used both for analytical as well as for preparative separations of mixtures of liquid substances. Different binary systems were separated. A theoretical separation stage number of 12 was obtained together with a height equivalent to one theoretical plate of 1.08 cm. Compared to the state of microtechnology this can be regarded as an excellent progress.     

Modellgestützter Reaktorentwurf auf Basis der optimalen Reaktionsführung

A novel methodology for the model‐based design of chemical reactors is presented. The aim of the method is the identification of the optimal reaction route and its technical realization. As an important characteristic of this novel approach, at the beginning a fluid element is considered on an abstract level. The fluid element is tracked over the reaction time and its state is optimally adjusted at any time. The advantage of this approach is that at the early design stage no constraints owing to predefined apparatus specific limitations are narrowing the solution space. That way it is possible to quantify the maximum potential of the reaction system.     

MINLP‐Optimierung des Hybridverfahrens Destillation/Schmelzkristallisation

The hybrid separation process distillation/melt crystallization offers a cost wise attractive alternative compared to conventional distillation processes. In this work, the systematic and cost optimal design of this combination process is considered. The focus is on the optimal choice of operating and structural degrees of freedom.     

Labortest zur Minimierung des Versuchsaufwandes bei Pilotfiltrationen

Investigating beer filtration using cellulose fibers requires appropriate methods. One aspect is the preparation of large scale trials. Starting from the filterability test according to Raible and based on the results of diverse pilot scale trials, a laboratory test was created. Apparatus, procedure and methods of assessing the results are described. The new test is qualified for reducing time and effort in upper scale trials, especially in case of varying filter aids compositions.