The present invention relates to a process for the production of high quality synthesis gas rich in hydrogen during the process of upgrading the residual hydrocarbon oil feedstock by rejuvenating the spent upgrading material in Reformer in absence of air/oxygen without supplying external heat source other than the heat generated inside the process during combustion of residual coke deposited on the upgrading material. The present invention further relates to the apparatus used for preparation of syngas wherein said syngas thus produced is used for production of hydrogen gas. Furthermore, the present invention also provides system and method for preparing pure hydrogen from syngas.