Process for manufacturing white pigment containing products

A process for manufacturing white pigment containing products, the process comprising the following steps:

• a) providing at least one white pigment and impurities containing material;
• b) providing at least one collector agent is selected from the group consisting of compounds of formula (1):
• wherein R1 is selected from the group consisting of
• i. a direct bond,
• ii. a C1-C20, linear or branched, saturated or unsaturated hydrocarbon chain optionally substituted by one or more —OH group(s), one or more methyl and/or methylene groups, a cycloalkylene group, a cycloalkenylene group and/or an arylene group;
• R2 is selected from the group consisting of a hydrocarbyl group having from 8 to 24 carbon atoms or a group of formula R4—O-(A′O)w-T- wherein,
• R4 represents a hydrocarbyl group having from 8 to 24 carbon atoms;
• w is a number within the range from 0 to 20;
• A′O is an alkyleneoxy group having from 2 to 4 carbon atoms;
• and
• T represents an alkylene group having from 1 to 6 carbon atoms;
• R3 is selected from the group consisting of a hydrocarbyl group or a benzyl group;
• AO represents an alkyleneoxy group having from 2 to 4 carbon atoms;
• X represents an anion derived from an alkylating agent R3X;
• x is a number within the range from 1 to 20;
• p is a number within the range from 1 to 15;
• t is 0 or 1;
• y is 0 or 1;
• and
• G represents a group of formula (2);
• wherein,
• B represents an alkyl group having from 1 to 4 carbon atoms or represents a benzyl group;
• s is 1, 2 or 3;
• R3, X and t are as defined above;
• N+ in formula (2) is connected to R2 in formula (1);
• and
• (CH2)s is connected to the quaternary nitrogen atom in formula (1);
• c) mixing the at least one white pigment and impurities containing material of step a) and the at least one collector agent of step b) in an aqueous environment to form an aqueous suspension;
• d) passing gas through the suspension formed in step c) to separate the white pigment from the impurities;
• and
• e) recovering the white pigment containing product by removing the white pigment from the aqueous suspension obtained after step d).