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J. Y. Hwang Vo1. 1, No. 2 134 Figure 1. The adsorption of anionic MR-30 (sodium oleate) on calcite and quartz at various pHs. The adsorption of MR-30 on calcite as various MR-30 dosages is shown in Figure 2. In the range of study, the amount of adsorption was almost linearly proportional to the magnetic reagent dosage. At the magnetic reagent dosage of 0.02 grams magnetite per gram of calcite, the magnetic susceptibility was increased from 3.94 x 10-6cgs/g to 437 x 10-6cgs/g. This demonstrates the strong magnetic enhancement capability through the adsorption of magnetic reagents.
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Vo1. 1, No. 2Adsorption of Surfactant Dispersed Nanometer Magnetite135Figure 2. Magnetic enhancement of calcite at various MR-30 dosages. MR-1 is a cationic magnetic reagent using lauric amind acetate as the outer layer surfactant. The adsorption of this magnetic reagent on quartz, kaolinite and pyrite at standard reagent dosage are shown in Figure 3. Lauric amine is a strong collector for these minerals in theflotation systems. Conditioning of MR-1 with these minerals also resulted in magnetic enhancement. The magnetic susceptibility of quartz was increased from 0.44 x 10-6cgs/g to 56.2 x 10-6cgs/g at pH 3. The adsorption gradually decreased with the increase of pH. At pH 11, magnetic enhancement is at 30.3 x 10-6cgs/g. Kaolinite adsorbed MR-1 quite constantly throughout the whole pH range of investigation. Magnetic susceptibility was increased from4.84 x 10-6cgs/g to 54.9 x 10-6cgs/g at pH 7. The adsorption of MR-1 strongly depended on the pH. At pH 3, the magnetic susceptibility of pyrite increased from 1.46 x 10-6cgs/g to 22.4 x 10-6cgs/g at 0.002 g/g magnetic reagent dosage. At pH 9, the magnetic susceptibility increased to 79.8 x 10-6cgs/g at the same reagent dosage. The surface charge on pyrite may be responsible for this change Figure 3. The adsorption of cationic MR-1 (lauric amine acetate) on quartz, kaolinite, and pyrite at various pHs.