Verfahren zur Wiederaufbereitung von Altpapier

摘要

Wastepaper is reprocessed in the presence of peroxides stabilised with flotation additives consisting of a combination of polyfunctional carboxylic acids (I) and polymeric cpds. (II). (I) is pref. maleic, fumaric, succinic, pyruvic, citric, gluconic, acrylic, adipic, tartaric or crotonic acid or an ester thereof. (II) and (a) homo- or co-polymers of (meth)acrylic or maleic acid or corresp. esters or amides in which the ester or amide gp. can also contain an alkylammonium gp., or polyphosphates or polymeric Al or Si cpds., or (b) condensation prods. of polyfunctional carboxylic acids with alkylamines contg. further amino or OH gp(s)., pref. ethanolamine, diethanolamine, ethylenediamine, melamine or urea, or condensation prods. of polyamidoamines, alkylene-polyamines or polyallylamines with aldehydes or chlorhydrin cpds., or (c) mixts. of cpds. (a) or (b). USE/ADVANTAGE - Prevents homolytic decomposition of the peroxide to inactive cpds. and also promotes the removal or dirt and ink, without undesirable environmental effects due to the formation of heavy metal complexes (contrast prior-art stabilisers).