by the procedure of this patent around 99 7 indicating a limit of recovery in the active sites for these catalysts quality hydrotreated primary light gas oil is measured in parts per million of sulfur in the case of deactivated catalyst a quality value of 250 ppm was taken like a production base example 2 achieves this quality at calculated temperature of 359 65 u00b0 c while the other options require 364 77 u00b0 c and 363 79 u00b0 c respectively therefore it can be considered that the solvent mixture reformate toluene isopropyl alcohol is better to reactivate the hds catalytic function as the starting run occurs at temperature of 360 u00b0 c to 237 ppm s as can be seen in table 8 while examples 3 and 4 to the same temperature condition obtained 308 and 293 ppm of sulfur respectively when comparing the deactivated catalyst versus in situ solvents washing catalysts we can mention that the improvement is given by reduction of total carbon in the catalysts this is about 22 28 the specific area is increased after solvent washing as well as the pore volume the effect is inverse for the average pore diameter decreasing values of 92 to 78 86 amstrong about the carbon type a decrease is observed only in the region of aliphatic carbon while aromatic carbon was increased the carbon nmr aliphatic aromatic ratio for catalysts washed in situ with solvents were lower than in the deactivated catalyst in table 10 can be confirmed that the active species of the washed catalyst with are higher than deactivated catalyst this is evidence that the process for reactivating deactivated catalysts was successful regarding the improvement of the active sites present particularly for the species mos 2 increased 57 7 to average.