Gottfried Faleschini

Hydrogen production by steam–iron process

The steam-iron process is one of the oldest methods of producing hydrogen. It is a cyclic process for water cleavage, whereby coal is consumed. Coal is gassified to a lean reducing gas, containing carbon monoxide and hydrogen. This gas reacts with iron oxides (haematite Fe 2 O 3 , magnetite Fe 3 O 4 , wuestite FeO) to produce a reduced form of iron oxide (wuestite FeO, iron Fe). The reduced iron oxide is re-oxidised with steam to form magnetite and hydrogen. After studies concerning theoretical limitations, the subsequent practical realisation by construction of a suitable laboratory prototype reactor was performed. Further, the investigation and optimisation of process variables, accompanied by respective chemical analyses, and finally the simulation of the whole process and the design of a demonstration plant for electricity generation system in the range of 10 MW were carried out. The resulting overall efficiency (heat and electricity) of the respective power plant was calculated as 35% and the electrical efficiency at about 25%. The operation of the small scale Sponge Iron Reactor (SIR) showed that the hydrogen produced is sufficiently pure for use in any kind of fuel cell (CO < 10 ppm).

Alkaline fuel cells applications

Abstract On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in todays motive power techniques in terms of environmental compatibility, consumers profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen–air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H2–air fuel cell and lead–battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

Cyclotrisulfimide - Synthesis and Properties

Abstract Cyclotrisulfimide (1,3,5,2,4,6- trithiatriazine-1,1,3,3,5,5-hexoxide) (1) has been synthesized successfully from persilylated sulfanuric acid (2) and hydrogen chloride in dichloromethane and has been isolated in pure form. Correlations of infrared and 15N-NMR spectra support assignment of the imide structure of (1). Ring cleavage appears to characterize reactions of (1) with solvolytic reagents. Thermal decomposition of (1) has been studied by TG accompanied by TLC methods. Reaction with diazomethane in dioxane yields the N,N,N-trimethyl derivative (3). Hitherto unknown (2) has been prepared from the trisilver salt of (1) using uimethylchlorosilane. The compound (2) has been characterized by IR, 15N-NMR and by X-ray crystallography. In the structure the S3N3 ring adopts a flattened chair conformation with the silyl groups being axial.

An Easy Access to Hydrazinocarbonyl Carbamic Acid Ethyl Esters

Summary. The reaction of carboisocyanatidic acid ethyl ester with hydrazines and 3,5-dioxo-1,2,4-triazolidine is reported. The thermal cyclization of the products to 1-substituted 3,5-dioxo-1,2,4-triazolidines and to [1,2,4]triazolo[1,2-a][1,2,4]triazole-1,3,5,7-tetraone was investigated.Zusammenfassung. Die Reaktion von Ethoxycarbonylisocyanat mit Hydrazinen und 3,5-Dioxo-1,2,4-triazolidin und die thermische Zyklisierung dieser Produkte unter Bildung von 1-substituierten 3,5-Dioxo-1,2,4-triazolidinen und [1,2,4-]Triazolo[1,2-a][1,2,4]triazolo-1,3,5,7-tetraon wurde untersucht.

29Si- und13C-NMR-Untersuchungen zur Struktur persilylierter Urazole

The molecular structures of persilylated urazoles: tris-trimethylsilyl-urazole, bis-trimethylsilyl-4-methyl-urazole, bis-trimethylsilyl-4-methyl-dithio-urazole, and tris-trimethylsilyl-cyanurate have been determined by29Si-,13C-NMR and IR measurements.