Combination hydrorefining, heat-treating and hydrocracking process

Claim 1

A process for upgrading a heavy hydrocarbonaceous oil feed, which comprises the steps of: (a) contacting said oil feed with added hydrogen in the presence of a hydrorefining catalyst at hydrorefining conditions, in a hydrorefining zone; (b) heat-treating at least a portion of the entire effluent of said hydrorefining zone, said portion including normally liquid hydrocarbons and hydrogen, in a heat-treating zone, in the absence of a catalyst at conditions such as to avoid any significant cracking of said normally liquid hydrocarbons, said conditions including a temperature in the range of about 500° to about 720° F., for a period of time ranging from about 0.25 hour to about 6 hours; (c) passing at least a portion of the entire heat-treated effluent, including hydrogen and normally liquid hydrocarbons, to a hydrocracking zone; (d) subjecting said portion of heat-treated effluent to hydrocracking conditions in the presence of a hydrocracking catalyst in said hydrocracking zone, and (e) recovering a hydrocracked normally liquid hydrocarbonaceous product.