A continuous process for converting waste plastic into recycle for polypropylene polymerization is provided. The process integrates refinery operations to provide an effective and efficient recycle process. The process comprises selecting waste plastics containing polyethylene and polypropylene and then passing the waste plastics through a pyrolysis reactor to thermally crack at least a portion of the polyolefin waste and produce a pyrolyzed effluent. The pyrolyzed effluent is separated into offgas, a naphtha/diesel fraction, a heavy fraction, and char. The naphtha/diesel fraction is passed to a refinery FCC unit, from which is recovered a liquid petroleum gas C3 olefin/paraffin mixture. The C3 paraffins and C3 olefins are separated into different fractions with a propane/propylene splitter. The C3 olefin fraction is passed to a propylene polymerization reactor. The C3 paraffin fraction is optionally passed to a dehydrogenation unit to produce additional propylene and then the resulting C3 olefin is passed to a propylene polymerization reactor. The heavy fraction of pyrolyzed oil is passed to an isomerization dewaxing unit to produce a lubricating base oil.