Electrostatic modification reagent and process for enhancing electrostatic separation in the beneficiation of ores

An electrostatic modification reagent for beneficiating a mineral substrate by electrostatic separation, wherein the mineral substrate includes a conducting mineral component and/or a non-conducting mineral component, said reagent comprising:

• at least one electrostatic modifier comprising an organic compound selected from the group consisting of
• quaternary amines;
• imidazoline compounds;
• dithiocarbamate compounds;
• pyridine compounds;
• pyrrolidine compounds;
• conducting polymers;
• polyethyleneimines;
• compounds of formula (IV):
• R—(CONH—O—X)n (IV)
• wherein n of formula (IV) is 1 to 3;
• wherein R of formula (IV) comprises from 1 to 50 carbons;
• and wherein each X of formula (IV) is individually selected from the group consisting of H, M, and NR′4, where M is a metal ion and each R′ is individually selected from the group consisting of H, C1-C10 alkyl, C6-C10 aryl, C7-C10 aralkyl, and C10-C18 naphthylalkyl;
• compounds of formula (VI):
• wherein R8 of formula (VI) is selected from the group consisting of H, C1-C22 alkyl, C6-C22 aryl, C7-C10 aralkyl, and C10-C18 naphthylalkyl;
• and X of formula (VI) is selected from the group consisting of H, M, and NR′4, where M is a metal ion and each R′ is individually selected from the group consisting of H, C1-C10 alkyl, C6-C10 aryl, C7-C10 aralkyl and C10-C18 naphthylalkyl;
• and mixtures thereof;
• a plurality of particles having an average specific resistivity that is greater than or equal to the specific resistivity of the non-conducting mineral component of the mineral substrate when the non-conducting mineral component is electrostatically modified;
• and/or
• a plurality of particles having an average specific resistivity that is less than or equal to the specific resistivity of the conducting mineral component of the mineral substrate when the conducting mineral component is electrostatically modified,
• wherein the electrostatic modifier and plurality of particles are present in a weight ratio of electrostatic modifier to particles of from 100:1 to 1:100.