Abstract: Binding effects and mechanisms of organic binders on the magnetite concentrate have been investigated by pelletizing test， FTIR analysis， measurements of zeta potential， contact angle， and binder solution viscosity. Results indicate that wet strengths of pellets with guar gum are the largest， followed by CMC and CMS. Furthermore， it presents a significant positive correlation between the dosage of organic binders and dry pellet strengths. FTIR analysis illustrates that CMS and CMC can adsorb onto the magnetite concentrate by carboxyl methyl and hydroxyl， while the adsorption of guar gum onto the magnetite concentrate is mainly through hydroxyl. Meanwhile， CMS and CMC can increase the negative charge of the magnetite concentrate surface， while guar gum reduces that of the magnetite concentrate. Besides， the adsorption of organic binders on the magnetite concentrate decreases the contact angle and increases the wettability of the magnetite concentrate with water. Results also show that the bigger the viscosity of the binder solution is， the higher the wet strengths of the magnetite concentrate pellets are under the same binder concentration.

Key words: organic binder, iron ore pellet, carboxyl methyl starch, carboxyl methyl cellulose, guar gum