Method of Refining Waste Plastic Pyrolysis Oil Using Waste Tire Pyrolysis Oil and Molybdenum-Based Hydrotreating Catalyst, and Continuous Operation Method Thereof

Abstract

The present disclosure relates to a method of refining waste plastic pyrolysis oil comprising: mixing waste plastic pyrolysis oil and waste tire pyrolysis oil to produce a mixed oil; hydrotreating the mixed oil with a reaction gas comprising hydrogen gas (H2) in the presence of a molybdenum-based hydrotreating catalyst; and removing a by-product of the hydrotreating from a product of step (S2) to obtain refined oil. The method of refining waste plastic pyrolysis oil disclosed herein may produce refined oil having a significantly low content of impurities such as chlorine, nitrogen, oxygen, and/or metals, and reduces the environmental load due to waste tires by diverting waste tire pyrolysis oil to supply a continuous sulfur source, such that the refining device may operate continuously for a long period of time.

1 . A method of refining waste plastic pyrolysis oil, the method comprising the steps of:
 (S1) mixing waste plastic pyrolysis oil and waste tire pyrolysis oil to produce a mixed oil, wherein the waste tire pyrolysis oil is comprised in an amount of more than 0 parts by weight and less than 100 parts by weight with respect to 100 parts by weight of the waste plastic pyrolysis oil;   (S2) hydrotreating the mixed oil with a reaction gas comprising hydrogen gas (H 2 ) in the presence of a molybdenum-based hydrotreating catalyst; and   (S3) removing a by-product of the hydrotreating from a product of step (S2) to obtain refined oil.   
     
     
         2 . The method of  claim 1 , wherein the mixed oil comprises 300 ppm or more of sulfur. 
     
     
         3 . The method of  claim 1 , wherein the waste tire pyrolysis oil is comprised in an amount of more than 0 parts by weight and less than 50 parts by weight with respect to 100 parts by weight of the waste plastic pyrolysis oil. 
     
     
         4 . The method of  claim 1 , wherein the reaction gas in step (S2) comprises hydrogen sulfide gas (H 2 S). 
     
     
         5 . The method of  claim 4 , wherein the hydrogen sulfide gas (H 2 S) is separated from the by-product of the hydrotreating removed in step (S3) and then re-supplied to step (S2). 
     
     
         6 . The method of  claim 1 , wherein the molybdenum-based hydrotreating catalyst is a catalyst in which a molybdenum-based metal, or a metal comprising one or two or more selected from nickel, cobalt, and tungsten and a molybdenum-based metal, are supported on a support. 
     
     
         7 . The method of  claim 1 , wherein the molybdenum-based hydrotreating catalyst comprises a molybdenum-based sulfide hydrotreating catalyst. 
     
     
         8 . The method of  claim 1 , wherein step (S2) is performed at a pressure of 200 bar or less. 
     
     
         9 . The method of  claim 1 , wherein step (S2) is performed at a temperature of 300° C. or higher and lower than 450° C. 
     
     
         10 . The method of  claim 1 , wherein step (S2) is performed at a liquid hourly space velocity (LHSV) of 0.1 to 10 h −1 . 
     
     
         11 . The method of  claim 1 , wherein the mixed oil further comprises a sulfur source. 
     
     
         12 . The method of  claim 11 , wherein the sulfur source comprises sulfur-containing oil. 
     
     
         13 . The method of  claim 12 , wherein the sulfur-containing oil is comprised in an amount of 100 parts by weight or less with respect to 100 parts by weight of the waste plastic pyrolysis oil. 
     
     
         14 . The method of  claim 11 , wherein the sulfur source comprises one or two or more sulfur-containing organic compounds selected from a disulfide-based compound, a sulfide-based compound, a sulfonate-based compound, and/or a sulfate-based compound. 
     
     
         15 . A continuous operation method of a device of refining waste plastic pyrolysis oil, the continuous operation method comprising the steps of:
 (S1) mixing waste plastic pyrolysis oil and waste tire pyrolysis oil to produce a mixed oil, wherein the waste tire pyrolysis oil is comprised in an amount of more than 0 parts by weight and less than 100 parts by weight with respect to 100 parts by weight of the waste plastic pyrolysis oil;   (S2) hydrotreating the mixed oil with a reaction gas comprising hydrogen gas (H 2 ) and hydrogen sulfide gas (H 2 S) at a pressure of 200 bar or less in the presence of a molybdenum-based sulfide hydrotreating catalyst; and   (S3) removing a by-product of the hydrotreating from a product in step (S2) to obtain refined oil,   wherein the hydrogen sulfide gas (H 2 S) in step (S2) is separated from the by-product of the hydrotreating in step (S3), and the separated hydrogen sulfide gas (H 2 S) is re-supplied to step (S2).   
     
     
         16 . The continuous operation method of  claim 15 , wherein the mixed oil contains 300 ppm or more of sulfur. 
     
     
         17 . The continuous operation method of  claim 15 , wherein the waste tire pyrolysis oil is comprised in an amount of more than 0 parts by weight and less than 50 parts by weight with respect to 100 parts by weight of the waste plastic pyrolysis oil. 
     
     
         18 . The continuous operation method of  claim 15 , wherein the mixed oil further comprises a sulfur source. 
     
     
         19 . The continuous operation method of  claim 18 , wherein the sulfur source comprises sulfur-containing oil. 
     
     
         20 . The continuous operation method of  claim 19 , wherein the sulfur-containing oil is comprised in an amount of 100 parts by weight or less with respect to 100 parts by weight of the waste plastic pyrolysis oil.