Abstract: The depressing performance of 2,4-dihydroxy-benzoic acid to hematite and quartz was studied via single mineral flotation and the results show that it has better depression to quartz, but less affect on hematite. When the pH of pulp is 8.4 with 30.4 mg/L of sodium oleate as collector and 40.2 mg/L of 2,4-dihydroxy-benzoic acid as depressant, iron concentrate grading at 64.03% with a 90.66% iron recovery was obtained from the artificial mixed ores(mixing ratio at 3:2) of hematite and quartz. The Zeta potentials measurements and FTIR spectra analysis showed that the depressing performance of 2,4-dihydroxy-benzoic acid to the surface of quartz mainly relies on the hydrogen-bonding adsorption.

Key words: 2,4-dihydroxy-benzoic acid, Quartz, Hematite, Depressing performance, Hydrogen-bonding adsorption