Abstract:his study synthesized PMA-EDTC with varying grafting rates and molecular weights, examining their impact on the inhibition behavior of galena during copper-lead separation. Additionally, the study delved deeply into the mechanism by which PMA-EDTC acts on the galena surface. The findings revealed that the molecular weight and grafting rate significantly influence the inhibitory effect on galena. There is a direct proportionality between the molecular weight of PMA-EDTC and its inhibitory impact on galena. Testing across different grafting rates revealed that the lead-inhibiting performance of PMA-EDTC does not positively correlate with the grafting rate; adsorption tests also demonstrated that the grafting rate does not directly proportional to the amount adsorbed by PMA-EDTC on the galena surface. Specifically, the adsorption amount of PMA-EDTC with a 15% grafting rate was higher than that of PMA-EDTC with 10% and 20% grafting rates. Further characterization, including TOF-SIMS, elucidated the lead-inhibiting mechanism of PMA-EDTC. The findings indicate that PMA-EDTC binds to lead ions on the galena surface, forming substances such as CHC6O3H9N2CS2Pb, thereby inhibiting the agglomeration of galena.