Liquid-full hydroprocessing to improve sulfur removal using one or more liquid recycle streams

摘要

The present invention provides a process for hydroprocessing hydrocarbons in liquid full reactors with one or more independent liquid recycle streams. The process operates as a liquid-full process, wherein all of the hydrogen dissolves in the liquid phase and one or more of the recycle streams may actually be zero. Hydrocarbons can be converted in the process to provide liquid products such as clean fuels with multiple desired properties.

主权项

1. A process for hydroprocessing a hydrocarbon feed, comprising: (a) providing two or more reaction stages disposed in sequence and in liquid communication, wherein each reaction stage contains at least one catalyst bed, and each catalyst bed contains at least one catalyst; (b) contacting the feed with (i) a diluent and (ii) hydrogen, to produce a feed/diluent/hydrogen mixture, wherein the hydrogen is dissolved in the feed/diluent/hydrogen mixture; (c) contacting the feed/diluent/hydrogen mixture with a first catalyst in a first reaction stage, to produce a first product effluent; (d) recycling a portion of the first product effluent as a first recycle stream for use in the diluent in step (b)(i) at a first recycle ratio of from about 0.1 to about 10; (d′) optionally having one or more current reaction stages between the first reaction stage and a final reaction stage, wherein step (d′) comprises (i) providing a preceding product effluent, which is the product effluent from a preceding reaction stage, to the current reaction stage; (ii) optionally contacting the preceding product effluent with hydrogen; (iii) optionally contacting the preceding product effluent with a current recycle stream; (iv) contacting the preceding product effluent with a current catalyst to produce a current product effluent; (v) optionally recycling a portion of the current product effluent as the current recycle stream at a current recycle ratio of from about 0.1 to about 10; and (vi) feeding the current product effluent to a subsequent reaction stage; (e) contacting at least a portion of a product effluent from the reaction stage preceding the final reaction stage, and optionally hydrogen, with a final catalyst in the final reaction stage, to produce a final product effluent;
wherein each contacting step (c), optional step (d′)(iv), and (e) is performed under liquid-full reaction conditions, wherein the recycle ratio in a reaction stage cannot be larger than the recycle ratio in a preceding reaction stage, and wherein the final reaction stage has no recycle stream.