Ammonia, electrosynthesis

Electrosynthesis Co. Inc. [109,112, 113] has piloted a process that reduces cystine in aqueous ammonia solution, using an ElectroSyn cell. 

Electrosynthesis of ammonia has been achieved using a W(dppe)2 complex. Controlled potential electrolysis of trans-[W(NNH2) (dppe)2TsO]+ (382) (Scheme 138) in a THF-Bu4BF4-(Hg) system generates free NH3 and N2H4 along with... 

Scheme 2 Electrosynthesis of ammonia via tungsten bis(ditertiaryphosphine) species.

Modern electrochemical methods provide the coordination chemist with a powerful means of studying chemical reactions coupled to electron transfer and exploiting such chemistry in electrosynthesis. In addition, the electrochemical generation of reactive metallo intermediates can provide routes for the activation of otherwise inert molecules, as in the reduction of N2 to ammonia,50 and for electrocatalyzing redox reactions, such as the reduction of C02 to formate and oxalate,51 the oxidation of NH3 to N02-,52 and the technologically important oxidation of water to 02 or its converse, the reduction of 02 to water.53 Electrochemical reactions involving coordination compounds and organometallic species have been extensively reviewed.54-60... 

The electrochemical reduction is in competition with the reduction by sodium in liquid ammonia. The electrosynthesis can also be carried out under Birch condi-... 

The methodology used in chemical engineering to describe the performance of chemical reactors can be adapted to the study of electrochemical cells. Electrosynthesis of a variety of industrially relevant products has been studied for instance, the synthesis of ammonia from natural gas at atmospheric pressure (Marnellos et al., 2001 Wang et al., 2007). 

Dimethylhydrazine is currently prepared commercially by a modified Raschig process reacting dimcthylamine with the chloramine produced from ammonia and sodium hypochlorite. Formerly, it was prepared by the reduction of dimethylnitrosamine or by the reductive catalytic alkylation of carboxylic acid hydrazides with formaldehyde and hydrogen, followed by basic hydrolysis (Budavari et al. 1989 EPA 1984a, 1992b lARC 1974 Schmidt 1988). 1,2-Dimethylhydrazine may be prepared from dibenzoylhydrazine or by electrosynthesis from nitromethane (Budavari et al. 1989). 

Malononitrile salts. Electrosynthesis of air-stable potassium and ammonium salts of / -cycanophenyl malononitrile in liquid ammonia on a platinum grid electrode was reported Treating 10 with aliphatic alcohols and hydrohalic acids at elevated pressures gave dialkyl propanediimidate dihydrohalidesAcid addition salts (p-toluenesulfonate, methanesulfonate and hydrochloride) of aminomalononitrile were prepared ". Bis(methylthio)methylene-indanedione 123 reacted with 10 to yield 124 ". ... 

Pickett, C.J., Ryder, K.S. and Talarmin, J. Electron-transfer reactions in nitrogen fixation. Part 2. The electrosynthesis of ammonia Identification and estimation of products... 

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