Proposing a novel factor influencing flotation collector abilities to collect minerals by comparing two cationic collectors N,N-bis(2-hydroxy-3-chloropropyl) dodecylamine and dodecylamine

Abstract

Dodecylamine (DDA) is a commonly used cationic collector in the reverse flotation of apatite and quartz but has poor selectivity. To improve the selectivity of DDA, two 2-hydroxy-3-chloropropyl groups are introduced to the structure of DDA to create a novel cationic collector N,N-bis(2-hydroxy-3-chloropropyl) dodecylamine (BHCPDA). Flotation experiments demonstrate that BHCPDA has better selectivity than DDA. The findings from zeta potential experiments and X-ray photoelectron spectroscopy analysis consistently indicate that BHCPDA exhibits a greater adsorption amount on quartz surface compared to apatite. This observation explains its heightened ability for collecting quartz in the flotation relative to apatite. However, both the methods also reveal that BHCPDA displays a higher adsorption amount on apatite surface than DDA, whereas DDA demonstrates a greater efficiency in collecting apatite. This implies that the efficacies of flotation collectors in collecting minerals are not solely dependent on their adsorption amounts on the mineral surfaces. First-principles calculations indicate that BHCPDA and DDA adopt distinct adsorption configurations on quartz surface, leading to a reduced collecting ability of BHCPDA for quartz. The integration of the flotation experiments with the various test methods leads to the conclusion that the adsorption configurations of collectors on mineral surfaces significantly influence their abilities to collect the minerals.