Reaktive polymere Träger für die Immobilisierung von Enzymen

Reactive and hydrophilic carriers with macroreticular structure and with excellent mechanical stability were synthesized by copolymerization of 4-isothiocyanato styrene and acrylic acid with different amounts of 1,4-divinylbenzene as crosslinking agent in the presence of petroleum ether. The porosity and the swellability of the carriers was investigated. The binding ability for trypsin was determined in dependence of the composition and of the grain size of the carriers and as a function of the offered amount of the enzyme during the immobilization. For the immobilized enzyme the pH/activity-profiles and the effectiveness were determined and the effects of buffers were investigated.     

Rohrfertigung für den Reparaturbereich

Pipe fabrication for the repair sector. The paper discusses the changes in pipe fabrication that have taken place in recent years. These enable repair work to be carried out more efficiently, without thereby impairing the flexibility and speed of operation that are essential to maintenance work. A prerequisite for this is that work on the pipes be transferred to workshops. Only here is it possible for manual operations, such as manual welding, to be reduced to a minimum and be replaced by mechanized or semi-mechanized welding methods. The use of modern machines for bending the pipes is more economic than the welding in of pipe bends. Necking out of the pipes by mechanical means or the use of mechanically pre-fabricated connections permit optimum preparation of the weld seam for branch fittings. Any additional work on the pipes, where this is necessary, is carried out at workplaces specially designed for the purpose.     

Verfahrenstechnik für den Umweltschutz

Industrial process engineering and environmental protection . Industrial process engineering involves not only the realization of chemical-physical processes but also the optimization of the economics of a plant and the minimization of environment pollution. Since the incorporation of additional facilities in a process for the reduction of emission has been brought to a high technical standard in recent years, more and more attention will now be directed to achieving a high selectivity in favor of the product in the chemical reaction by suitable process control. It is shown with the aid of schematically represented mass balances and cost diagrams that emission can be reduced by process engineering optimization of a process, leading to a decrease in both the costs incurred from environmental pollution and the costs for the preventative measures taken.     

Katalysatoren für den Umweltschutz

Catalysts for environmental protection. The main emitters of anthropogenic air pollution are internal combustion engines, power plants, and production processes. Components of exhaust gases which are regarded as pollutants are hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NO_x), sulfur dioxide (SO₂), and dust. Three main types of catalyst are understood to improve the environment; namely automotive emission control, NO_x abatement and oxidation. To reduce the pollutants HC, CO, and NO_x in automobile exhaust gas, three-way catalysts are currently applied. The reduction of particle emissions in diesel exhaust gas is achieved by diesel filters and oxidation catalysts. Pollutants from power plants are mainly the inorganic components NO_x and SO₂. In the SCR process, NO_x is catalytically reduced to nitrogen and water. The DESONOX process is suited for the simultaneous catalytic abatement of NO_x and SO_x. Exhaust gases from production processes in many areas require after-treatment. Therefore catalyst formulations depend on process parameters and exhaust gas components. This overview presents and explains catalyst types, design, mode of operation, and processes.     

Verbrennungstechnik für den Umweltschutz

Combustion engineering for environmental protection. Use of combustion as a means of environmentally sound disposal of gaseous, liquid, and solid industrial production residues places new demands on combustion engineering, depending upon the properties of the residues. High temperature process engineering has the task of ensuring reliable disposal while satisfying legal requirements concerning the quality of combustion. Combustion engineering as a means of residue disposal raises many questions of a scientific and practical nature, which will all have to be answered.     

Über Modellwachse für den Metallpräzisionsguß

The Model Wax for the Precision Metal Castings After a short review of the history and the technique of precision metal casting on lost model waxes, the requisite properties of such waxes are given in details. The sum of all these properties can be achieved only by mixing different types of waxes with one another or by combination with other substances. At the same time, the molecular structure of the waxes also plays an important role. The relation between this and the shrinkage is shown by means of experimental investigations on a number of examples.     

Stationäre Chemische Energieumwandlung als Herausforderungen für den Verfahrensingenieur

Meeting future energy demands with more efficient, lower emission, and safe energy technologies has top priority in the medium term. Consumer-friendly energy concepts, integrated into regional and supraregional energy supply structures, represent further elements. These will make important contributions to resource-conserving and environmentally compatible power supplies utilizing local energy sources including renewable resources. Supplying energy to large areas involves additional tasks, from compensation of large amounts of fluctuating energy to the transport of fluctuating energy to the transport of renewable energy over long distances. Solar dish, parabolic section, and tower power generating plant have considerable economic and CO₂-reduction potential in sunny countries, such as in the Mediterranean region, However, the costs of solar-thermal electricity generation have to be reduced by a factor of 1.5 to 2. Fuel cell systems can attain particular significance as efficient low-emission energy conversion systems in power plant and automative engineering once their technical and economic potential can be realized.