Compositions and methods for selective separation of minerals from sulfide ores

A mineral flotation composition comprising an aqueous blend of a first depressant and a second depressant,

• wherein the first depressant is a polymer having a weight average molecular weight from 1,000 g/mol to 1,000,000 g/mol comprising:
• i) X units of an acrylamide derivative according to Formula (I):
• wherein
• each of R, R1, and R2 is independently chosen from H, C1-C4 alkyl, or C6-C12 aryl;
• and
• X is a residual mole percent fraction by weight based on the total mole percent by weight of Y and Z;
• ii) Y units of a thiourea derivative according to Formula (II):
• wherein
• R3 is chosen from H, a C1-C4 alkyl, or C6−C12 aryl;
• each of R4 and R5 is independently chosen from H, C1-C4 hydrocarbyl, or a C6−C12 aryl;
• and
• Y is a mole percent fraction from 1% to 50% by weight based on the total weight of X, Y, and Z;
• wherein X units of Formula (I) to Y units of Formula (II) are present at a weight ratio in a range from 10:90 to 95:5;
• and
• iii) Z units of a polymerization residue of any monomer copolymerizable with the derivatives according to Formulas (I) and (II), wherein Z is a mole percent fraction from 0% to 50% by weight based on the total weight of X, Y, and Z;
• and
• wherein the second depressant is a dithiocarbamate compound according to Formula (III):
• wherein
• R6 is chosen from H, or a Ci-C4 alkyl moiety having one or more functional groups selected from OH, SO3−M+, COO−M+, and CONR8R9, wherein each of R8 and R9 is independently chosen from H or C1-C4 alkyl;
• R7 is chosen from a C1-C4 alkyl moiety having one or more functional groups selected from OH, SO3−M+, COO−M+, and CONR8R9, wherein each of R8 and R9 is independently chosen from H or C1-C4 alkyl;
• and
• each instance of M is independently chosen from a cation selected from the group consisting of alkali metal, metal, or R104N+, wherein each instance of R10 is independently chosen from H or a C1-C6 alkyl,
• wherein the aqueous blend of the first depressant and second depressant is further characterized as having 4<pH≤14 at a temperature from −5° C. to 85° C.;
• and as being present at a weight ratio in a range from 20:80 to 80:20.