Schwartz catalyst

Schwartz s reagent (1) is an excellent catalyst for pinacolborane hydroboration of alkynes (Scheme 8-32) [234, 235]. 

Platinum-based catalysts are widely used in low-temperature fuel cells, so that up to 40% of the elementary fuel cell cost may come from platinum, making fuel cells expensive. The most electroreactive fuel is, of course, hydrogen, as in an acidic medium. Nickel-based compounds were used as catalysts in order to replace platinum for the electrochemical oxidation of hydrogen [66, 67]. Raney Ni catalysts appeared among the most active non-noble metals for the anode reaction in gas diffusion electrodes. However, the catalytic activity and stability of Raney Ni alone as a base metal for this reaction are limited. Indeed, Kiros and Schwartz [67] carried out durability tests with Ni and Pt-Pd gas diffusion electrodes in 6 M KOH medium and showed increased stability for the Pt-Pd-based catalysts compared with Raney Ni at a constant load of 100 mA cm and at temperatures close to 60 °C. Moreover, higher activity and stability could be achieved by doping Ni-Al alloys with a few percent of transition metals, such as Ti, Cr, Fe and Mo [68-70]. 

Recently, Schwartz and Shoer have described the use of (C5H5)2ZrCl2 as a catalyst in the reduction of CO by diisobutylaluminum hydride (DIBAH) (81). The products of this reaction, after aqueous acid workup, were methanol, ethanol, 1-propanol, and 1-butanol in decreasing amounts. A labeling... 

Tracer methods proposed by Schwartz et al. (19) and Colombo et al. (21) were used to determine total and external catalyst contacting efficiency. These techniques have been described elsewhere (22). Total contacting efficiency, r)c defined as the fraction of total (external and internal) catalyst area contacted by liquid can be obtained by ... 

All the correlations for the contacting efficiency qc (= total catalyst area contacted by liquid/total catalyst surface area) reported in the literature are for nonporous packing. These are summarized by Schwartz et al.84 and Table 6-6... 

D. E. Tutt and M. A. Schwartz. Model catalysts which simulate peniciUlnase. V. The cyclohep-taamylose-catalyzed hydrolysis of penicillins. /. Am. Chem. Soc., 93, 767-72 (1971)... 

Wu, X.X., Schwartz, V., Overbury, S.H., and Armstrong, T.R. Desulfurization of gaseous fuels using activated carbons as catalysts for the selective oxidation of hydrogen sulfide. Energy Fuels, 2005, 19, 1774. 

Analogous results, but with simple olefins comprising as much as 34-43% of the gaseous products, have been observed by Schwartz and Ciric 107) for methanol decomposition over REX and ZnX catalysts at higher temperatures (Table XI). Although decomposition by radical... 

The use of finely divided metallic molybdenum, tungsten and other members of this group as catalysts in the reduction of both oxides of carbon at temperatures of 800° to 850° C. has been patented by Schwartz-kopf.81 This process involves the use of an electric furnace lined with platinum, nickel, or platinum-nickel foil. The claim is made that 10 per cent of the reaction gases is transformed into methane in a single passage through the catalyst furnace. The advantage which tire above metals are claimed to possess over others applicable to the reaction is their ability to resist the action of various poisons and particularly suitor compounds. 

R.J. Matyi, H. Schwartz, J.B. Butt "Particle Size, Particle Size Distribution and Related Measurements of Supported Metal Catalyst". 

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