Combined PTA and PET plant waste water purification and recycle

A process for treating aqueous condensate liquor from a polyester plant 300 in an integrated terephthalic acid polyester plant comprises: contacting a portion of the aqueous condensate liquor from a polyester plant with an aqueous mother liquor from a terephthalic acid purification plant process to form a combined stream. The combined stream is provided to a pure plant mother liquor solvent extraction process 400 to separate the combined stream into an aqueous stream and organic stream. The aqueous stream is contacted with an alkali to form a pH adjusted stream and the pH adjusted stream is contacted with a filter to form a treated stream. The treated stream is contacted with a reverse osmosis unit to form an RO permeate stream. The permeate stream may be recycled back into the integrated PTA PET plant. Advantageously the process provides for water recovery and better water recycling thus reducing operating costs and providing a more environmentally friendly process.