Process for converting mixed waste plastic into liquid fuels and waxes by catalytic cracking

Abstract

The present invention relates to a process for converting mixed waste plastic into liquid fuels and waxes by catalytic cracking. The process comprises the steps of introducing mixed waste plastic and a catalyst comprising a zeolite-type catalyst within a reactor; allowing at least a portion of the mixed waste plastic to be converted to liquid fuels and waxes within the reactor; and removing a product stream containing said liquid fuels and waxes from the reactor.

1 . A process for converting mixed waste plastic into liquid fuels and waxes by catalytic cracking, the process comprising:
 introducing mixed waste plastic and a catalyst comprising a zeolite-type catalyst within a reactor;   allowing at least a portion of the mixed waste plastic to be converted to liquid fuels and waxes within the reactor; and   removing a product stream containing said liquid fuels and waxes from the reactor,   wherein the mixed waste plastic contains from 2 to 50% by weight of polystyrene and from 50 to 98% by weight of polyolefin, each based on the total weight of polystyrene and polyolefin in the mixed waste plastic, and wherein the weight ratio of catalyst to mixed waste plastic in the reactor is above 1:10.   
     
     
         2 . The process according to  claim 1 , wherein the mixed waste plastic contains from 2 to 40% by weight of polystyrene, based on the total weight of polystyrene and polyolefin in the mixed waste plastic. 
     
     
         3 . The process according to  claim 1 , wherein the weight ratio of catalyst to mixed waste plastic in the reactor is above 1:8. 
     
     
         4 . The process according to  claim 1 , wherein the weight ratio of catalyst to mixed waste plastic in the reactor is below 10:1. 
     
     
         5 . The process according to  claim 1 , wherein the catalyst predominantly is a zeolite-type catalyst. 
     
     
         6 . The process according to  claim 1 , wherein the catalyst consists of zeolite-type catalyst. 
     
     
         7 . The process according to  claim 1 , wherein the catalyst additionally comprises an amorphous-type catalyst. 
     
     
         8 . The process according to  claim 7 , wherein the amorphous-type catalyst comprises silica, alumina, kaolin, or a mixture thereof. 
     
     
         9 . The process according to  claim 1 , wherein the catalyst is fresh catalyst, equilibrated catalyst, or a mixture thereof. 
     
     
         10 . The process according to  claim 1 , wherein the temperature at which at least part of the mixed waste plastic is converted to liquid fuels and waxes in the reactor is above 350° C. 
     
     
         11 . The process according to  claim 1 , wherein the mixed waste plastic comprises more than 50% by weight of polystyrene and polyolefin, based on the total weight of the mixed waste plastic. 
     
     
         12 . The process according to  claim 1 , which wherein the process is conducted continuously. 
     
     
         13 . The process according to  claim 1 , wherein the waste plastic is selected from the group consisting of post consumer waste plastic, off-spec plastic and industrial scrap plastic. 
     
     
         14 . The process according to  claim 1 , wherein the waste plastic is essentially free of thermosetting polymers. 
     
     
         15 . The process according to  claim 2 , wherein the mixed waste plastic contains from 2 to 30% by weight of polystyrene, based on the total weight of polystyrene and polyolefin in the mixed waste plastic. 
     
     
         16 . The process according to  claim 15 , wherein the mixed waste plastic contains from 2 to 20% by weight of polystyrene, based on the total weight of polystyrene and polyolefin in the mixed waste plastic. 
     
     
         17 . The process according to  claim 3 , wherein the weight ratio of catalyst to mixed waste plastic in the reactor is above 1:5. 
     
     
         18 . The process according to  claim 4 , wherein the weight ratio of catalyst to mixed waste plastic in the reactor is below 7:1. 
     
     
         19 . The process according to  claim 10 , wherein the temperature at which at least part of the mixed waste plastic is converted to liquid fuels and waxes in the reactor is above 410° C. 
     
     
         20 . The process according to  claim 19 , wherein the temperature at which at least part of the mixed waste plastic is converted to liquid fuels and waxes in the reactor is in the range of above 410° C. to 500° C.