Process for producing hydrocarbons
A process for converting biomass to products is described. Biomass is contacted with hydrogen in the presence of a fluidized bed of hydropyrolysis catalyst in a reactor vessel under hydropyrolysis conditions; and products and char are removed from the reactor vessel. The products leave the fluidized bed at an exit bed velocity, the char has a settling velocity that is less than the exit bed velocity and hydropyrolysis catalyst has a settling velocity that is greater than the exit bed velocity.
1. A process for converting biomass to products comprising:
a. contacting the biomass with hydrogen in the presence of a fluidized bed of fresh hydropyrolysis catalyst in a reactor vessel under hydropyrolysis conditions;
b. removing products and char from the reactor vessel;
c. carrying out the contacting and removing steps for a period of time such that the fresh hydropyrolysis catalyst attrits in the fluidized bed to form small catalyst particles;
d. removing at least a portion of the small catalyst particles with the products and char wherein the products leave the fluidized bed at an exit bed velocity, the char has a settling velocity that is less than the exit bed velocity, the fresh hydropyrolysis catalyst has a settling velocity that is greater than the exit bed velocity, and the small catalyst particles have a settling velocity that is less than the exit bed velocity;
e. separating the products to remove the carbon monoxide and light hydrocarbons from the remainder of the products; and
f. passing the remainder of the products to a hydroconversion reactor wherein the remainder of the products are contacted with a hydroconversion catalyst under suitable hydroconversion conditions to produce a condensable liquid hydrocarbon product that has less than 1% oxygen.
2. A process as claimed in claim 1 wherein the settling velocity of the char is less than 90% of the exit bed velocity.
3. A process as claimed in claim 1 wherein the settling velocity of the char is less than 75% of the exit bed velocity.
4. A process as claimed in claim 1 wherein the settling velocity of the hydropyrolysis catalyst is greater than 110% of the exit bed velocity.
5. A process as claimed in claim 1 wherein the settling velocity of the hydropyrolysis catalyst is greater than 150% of the exit bed velocity.
6. A process as claimed in claim 1 wherein the settling velocity of the small catalyst particles is less than 90% of the exit bed velocity.
7. A process as claimed in claim 1 wherein the settling velocity of the small catalyst particles is less than 75% of the exit bed velocity.
8. A process as claimed in claim 1 where the small catalyst particles are separated out by a filter while the char is separated by a cyclone.