METHOD OF PRODUCING POLYOLEFIN RECYCLED MATERIAL Russian patent published in 2020 - IPC B29B17/02 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing polyolefin recycled material, particularly HDPE secondary material. Method of producing polyolefin recycled material suitable for production of consumer goods from mixed-colour wastes containing polyolefin involves the following stages: (i) treating polyolefin waste fraction with mixed colour with water without supply of heat energy, (ii) treating the polyolefin spent fraction obtained in (i) by washing with an aqueous-alkaline solution at a temperature of at least 60 °C, (iii) sorting polyolefin waste fraction obtained on (ii) into flakes to provide one or more single-color polyolefin spent fractions, each containing a polyolefin in concentrated form, wherein steps (ii) and (iii) can also perform in reverse sequence, (iv) treating one or more single-color polyolefin spent fractions obtained at previous steps at a temperature in range of 50 to 155 °C, preferably for 60 to 600 minutes. By said method, polyolefin secondary material can be obtained with substantially improved degree of purity compared to commercially available secondary raw material, wherein said secondary raw material can be used in production of a new package for consumer goods.

EFFECT: significantly preventing unpleasant odours associated with known polyolefin secondary raw material caused by products of destruction of migration materials formed during extrusion.

15 cl, 2 dwg