Stoichiometric Coefficients for HDS Reaction

In the liquid hydrocarbon mixture, a great variety of sulfur compounds is present. Due to this and because only bulk concentrations are measured for a single lump, for example, total sulfur content, it is not possible to know a priori the value of stoichiometric coefficients for the chanical reactions that are taking place. To overcome this disadvantage, the following generalized equation has been proposed in the literature (Korsten and Hoffmann, 1996)  

H2S stoichiometric coefficient can be determined by mass balance. By employing data of sulfur content in liquid at the entrance and exit of the reactor, the amount of sulfur that reacts can be calculated. Then, having the amounts of hydrogen sulfide in liquid and in gas phase, the following molar balance for H2S during HDS reaction can be established  

In laboratory experiments, it is common to feed a high-purity hydrogen stream, so that = 0 thus Equation 9.10 can be reduced to 

having the data of liquid mass and sulfur concentrations at the inlet and outlet of reactor and the amount of hydrogen sulfide after separation of phases, it is possible to derive from Equation 9.12 by linear regression [y = m = Vhjs/Vhc-s.. r = (n//c-i,o - nuc-s)] the ratio hJ 0hc-s- 

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