Enumeration of RR

The microkinetic model described above comprises q = % surface intermediates, namely, H2OS, COS, CO2S, H2S, HS, OHS, OS and HCOOS. Consider the intermediates matrix 

Since rank a = 8, the surface intermediates are linearly independent and, hence, a direct RR involves no more that 9+l = 8 + l= 9 elementary reactions. It is further observed that 5i, sz, 53, and S5 (adsorption and desorption steps) should be involved in all full RRs. That is, it is not possible to obtain the OR by omitting these 4 elementary reactions. The remaining 9-4 = 5 elementary reactions involved in a RR need to be selected from among S4, sy, ss, s% s lo, S12, sw, Sis and sn. Thus, the total number of RRs does not exceed the number of ways 5 

A special situation is faced when considering the RR involving the elementary reactions Si, 52, 53, S4, Ss, s, Sj, 9 and iio- In this case all of the stoichiometric coefficients in the RR are zero 

A complete list of stoichiometrically distinct RRs, including ERs, for the WGSR is presented in Table 2. 

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