Roebuck reaction

The iodine produced in the Duslnnan process is rapidly reduced to iodide via the Roebuck reaction... 

The arsenous acid-iodate reaction is a combination of the Dushman and Roebuck reactions [145]. These reactions compete for iodine and iodide as intermediate products. A complete mathematical description has to include 14 species in the electrolyte, seven partial differential equations, six algebraic equations for acid-base equilibriums and one linear equation for the local electroneutrality. 

The iodate oxidation of arsenous acid is conveniently described in terms of two component processes (De Kepper et al., 1981a Hanna et al., 1982) process A, the Dushman reaction (Dushman, 1904), and process B, the Roebuck reaction (Roebuck, 1902). 

The introduction cf steam into the chambers has been already mentioned. Previously to the use of this reagent, the water on the floor of tire chamber had all the work to. do every particle of the sulphuric acid and nitrous compound was compelled to pass in to the water from whatever portion of the chamber it was formed in order to be decomposed, The interior cf one of Dr, Roebuck s chambers, or any other chamber worked in the same manner, while in action would have boon a pretty sight the reactions must have taken place consecutively, as described in a pre-[ ceding portion of this article when treating of the... 

In hydrochloric acid solution arsenious acid is oxidised by iodine, but the reaction is reversible owing to the reducing action of hydriodic acid. The kinetics of the reaction were first investigated by Roebuck,2 who concluded that the balanced reaction could be represented thus—... 

Process (VIA) is the net reaction in excess arsenite ([H3As03]o/[IOJ]0 > 3) it is equivalent to (VIB) + 3 (VIC). Process (VIB), the Dushman reaction, is normally rate determining. Therefore, the net process (VIA) is autocatalytic in [I-], which causes a dramatic color change to arise at the stoichiometric point due to the sudden appearance of I2. Bognar and Sarosi exploited this fact to devise a chronometric technique for the determination of traces of iodide43. Process (VIC), the Roebuck reaction44, has played an important role in the development of chemical kinetics and teaching of physical chemistry, as it was the first multi-step reaction for which it was shown that the quotient of the independently determined forward and reverse rate laws equals the equilibrium quotient obtained from the law of mass action. 

The results of Roebuck and Evering (15) who used A1 Cl 3-type catalysts and temperatures down to -20 C can also be explained by the production of esters with both 2-butene and ethylene. They had found that Improved alkylate qualities occurred as the reaction temperature was decreased, but yields of alkylate were significantly reduced at lower temperatures. Probably they would have obtained in all cases high yields of alkylate If they had provided longer residence times for some of the lower temperature runs presumably sufficient time had not always been allowed for complete reaction of all the esters. 

Roebuck, J. R. 1902. The Rate of the Reaction between Arsenous Acid and Iodine in Acidic Solution. The Rate of the Reverse Reaction and the Equilibrium between Them, J. Phys. Chem. 6, 365-398. 

The first time a catalyst was used in the chemical industry was in 1746 by J Roebuck, in the lead chamber process. The lead chamber process was the first approach to the industrial production of sulfuric acid. In it, sulfur dioxide is oxidized by nitrogen dioxide in the presence of water. This reaction was carried out in wooden chambers lined with lead. 

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