A method for the mechanical selection and separation of at least two polymers from a mixture of polymers originating from commercial and/or industrial plastic waste, said method comprising the steps of: i. providing a mixture of polymers from commercial and/or industrial plastic waste consisting of flakes of said polymers of sizes from 6 to 100 mm; ii. identifying by means of near-infrared spectroscopy the flakes of coloured and white plastic material and separating a fraction rich in said flakes of coloured and white plastic material from a fraction rich in flakes of black plastic material by suitable separation means; iii. identifying by means of the NIR spectroscopy the flakes of a polymer P1 from said fraction rich in flakes of coloured and white plastic material separated in step ii, and separating a fraction rich in flakes of polymer P1 from said fraction rich in flakes of coloured and white plastic material by means of suitable separation means, obtaining a fraction poor in flakes of polymer P1; iv. identifying by means of the NIR spectroscopy the flakes of polymer different from P1 from the fraction rich in flakes of polymer P1 separated in step iii and separating a fraction rich in flakes of polymers different from P1 from said fraction rich in flakes of polymer P1 by means of appropriate separation means; v. identifying by means of the NIR spectroscopy the flakes of a polymer P2 from said fraction poor in flakes of polymer P1 separated in step iii and from said fraction rich in flakes of polymers different from P1 separated in step iv, and separating a fraction rich in flakes of polymer P2 from said fraction rich in flakes of coloured and white plastic material by means of appropriate separation means, obtaining a fraction poor in flakes of polymer P2; vi. identifying by means of the NIR spectroscopy the flakes of polymers different from P2 from the fraction rich in flakes of polymer P2 separated in step v and separating a fraction rich in flakes of polymers different from P2 from said fraction rich in flakes of polymer P2 by means of appropriate separation means. i. providing a mixture of polymers from commercial and/or industrial plastic waste consisting of flakes of said polymers of sizes from 6 to 100 mm; ii. identifying by means of near-infrared spectroscopy the flakes of coloured and white plastic material and separating a fraction rich in said flakes of coloured and white plastic material from a fraction rich in flakes of black plastic material by suitable separation means; iii. identifying by means of the NIR spectroscopy the flakes of a polymer P1 from said fraction rich in flakes of coloured and white plastic material separated in step ii, and separating a fraction rich in flakes of polymer P1 from said fraction rich in flakes of coloured and white plastic material by means of suitable separation means, obtaining a fraction poor in flakes of polymer P1; iv. identifying by means of the NIR spectroscopy the flakes of polymer different from P1 from the fraction rich in flakes of polymer P1 separated in step iii and separating a fraction rich in flakes of polymers different from P1 from said fraction rich in flakes of polymer P1 by means of appropriate separation means; v. identifying by means of the NIR spectroscopy the flakes of a polymer P2 from said fraction poor in flakes of polymer P1 separated in step iii and from said fraction rich in flakes of polymers different from P1 separated in step iv, and separating a fraction rich in flakes of polymer P2 from said fraction rich in flakes of coloured and white plastic material by means of appropriate separation means, obtaining a fraction poor in flakes of polymer P2; vi. identifying by means of the NIR spectroscopy the flakes of polymers different from P2 from the fraction rich in flakes of polymer P2 separated in step v and separating a fraction rich in flakes of polymers different from P2 from said fraction rich in flakes of polymer P2 by means of appropriate separation means.