Process for the treatment of mixed plastic-containing waste

The invention relates to a process for the treatment of mixed plastic-containing waste comprising at least 50 wt. % of plastic, wherein an aqueous slurry comprising the mixed plastic-containing waste and an aqueous phase is kept at a temperature above 180° C. during a residence step with a residence time of between 5 minutes and 5 hours, the pressure being at least autogenous, and wherein the aqueous slurry comprising the mixed plastic-containing waste and the aqueous phase is subsequently cooled in a cooling procedure to at least a temperature at which the plastic fraction that was molten during the residence step, solidifies, and purified mixed plastic particles are formed, the temperature at which the aqueous slurry is kept during the residence step being chosen such that at least 80 wt. % of the plastic melts, and in which process the formation of purified mixed plastic particles having at least one dimension larger than 20 mm is prevented through agitation during at least part of the pre-heating step, the residence step and/or the cooling procedure.