An apparatus (100) is provided for thermal or thermal-catalytic degradation of feedstock. The apparatus includes a retort vessel (102). The retort vessel (102) is configured to receive feedstock. Further, the retort vessel includes at least one partition structure (106), wherein the partition structure (106) divides the retort vessel into volumetric zones and extends from an input end (122) of the retort vessel (102) to an output end (124) of the retort vessel (102). The retort vessel (102) is declined to facilitate movement of the feedstock from an input end (122) of the retort vessel (102) towards output end (124) of the retort vessel (102). Further, the retort vessel (102) is configured to rotate angularly and heated to facilitate thermal or thermal-catalytic degradation of the feedstock.