Plastic pyrolysis oil pretreatment

A process for converting waste plastics to refining feedstock comprising:

• (a) conducting pyrolysis of a plastic feedstock comprising waste plastics to produce a liquid stream of plastic pyrolysis oil, an off-gas stream, and a solids stream;
• (b) directly feeding the liquid stream of plastic pyrolysis oil to an adsorption based purification process comprising treatment of the liquid stream of plastic pyrolysis oil in three or more adsorption vessels to generate a treated plastic pyrolysis oil stream comprising less than 10 ppmw nitrogen, less than 10 ppmw sulfur, less than 10 ppmw chlorine, and less than 10 ppmw oxygen, the adsorption based purification process comprising:
• i) contacting the liquid stream of plastic pyrolysis oil with one or more adsorbent materials in each of the three or more adsorption vessels, the adsorbent materials configured for adsorption of organic molecules comprising one or more atoms of sulfur, nitrogen, oxygen, or chlorine, wherein:
• the liquid stream of plastic pyrolysis oil is contacted with the one or more adsorbent materials in the three or more adsorption vessels at a temperature of 20 to 80° C., a pressure of 1 to 10 bars, and at a liquid hourly space velocity of 0.1 to 1 hours−1;
• at least one of the one or more adsorbent materials are configured for adsorption of organic molecules comprising each of sulfur, nitrogen, oxygen, and chlorine, and
• at least two of the three or more adsorption vessels comprise differing compositions of the adsorbent material;
• and
• ii) discharging the treated plastic pyrolysis oil stream from the three or more adsorption vessels;
• and
• (c) collecting the treated plastic pyrolysis oil stream from the three or more adsorption vessels for further processing into value added products as a feedstock for conventional refining processes.