Patent ID: 7442345

Claim:
A reactor apparatus for the manufacture of acrylonitrile with decreased afterburning comprising: a reactor vessel defining a dense bed zone, a catalyst disengaging zone, and a dilute phase zone; wherein the dense bed zone contains a fluidized bed of particulate catalyst and, optionally, a heat transfer apparatus located within the fluidized bed of particulate catalyst; wherein the catalyst disengaging zone is positioned above the dense bed zone for separating and returning a first portion of entrained catalyst in a product gas mixture to the dense bed zone; and wherein the dilute phase zone is positioned above the catalyst disengaging zone, the dilute phase zone being defined in part by a domed hemispherical-or elliptical-capped top portion of the reactor vessel, the diameter of the top portion being smaller than the diameter of the disengaging zone; a grid positioned within the reactor vessel, below the fluidized bed of particulate catalyst at least one gas distribution system for supplying a reactant gas to the fluidized bed of particulate catalyst, the at least one gas distribution system being postioned near the upper surface of the grid; at least one gas inlet supplying a reactant gas to the fluidized bed of particulate catalyst, the at least one gas inlet being positioned below the grid and within a conically shaped bottom of the reactor vessel; a gas cooler postioned at least partially within the top portion of the dilute phase zone, for cooling the product gas mixture containing a second portion of entrained catalyst separation apparatus for separating the second portion of entrained catalyst from the product gas mixture, the catalyst separation apparatus being positioned within the reactor vessel and downstream from the gas cooler such that the product gas mixture containing the second portion of entrained catalyst is transported from the gas cooler to the catalyst separtion apparatus; means for returning separated catalyst from the catalyst separation apparatus to the dense bed zone; and at least one gas outlet for discharging the separated product gas mixture from the reactor vessel, the at least one gas outlet being positioned at the dilute phase zone.