破碎解理方式对高岭石颗粒电动特性的影响

Effect of breakage and cleavage ways on the electrokinetic properties of kaolinite particles

为了掌握不同粒度高岭石颗粒的电动特性,利用ZetaProbe分析仪测定了其在溶液中的表面ζ电位,分析了不同解理方式对颗粒各面面积的影响,研究了破碎解理方式对高岭石颗粒在溶液中电动特性的影响规律.结果表明:D_(50)分别为0.30,4.65和7.95 mm 3种高岭石颗粒的等电点(IEP)随粒度的增加呈先降后增的趋势;3.00<pH<7.40时,高岭石颗粒表面的负ζ电位与粒度正相关,而pH≥7.40时,随粒度的增加呈先降后增的趋势;T-O解理会使高岭石颗粒酸碱响应系数α值减小,E-E解理则会增大颗粒的α值;大粒度高岭石破碎时T-O解理较多,随颗粒粒度的减小,E-E解理逐渐增多是不同粒度高岭石颗粒群电动特性的主要成因.

In order to study the electrokinetic properties of different sizes kaolinite particles, the zeta potentials in aqueous solutions were determined by the ZetaProbe analyzer. The effects of breakage and cleavage ways on the electrokinetic properties of kaolinite particles were analyzed according to the changes of each surface area caused by different cleavage ways. The results show that the IEP of 0.30, 4.65 and 7.95 mm kaolinite particles decreased first and then increased with the increasing of size from 0.30 mm to 7.95 mm. The negative zeta potential increased when 3.00〈pH〈7.40, and decreased first and then increased when pHi7.40. The T-O cleavage and E-E cleavage will decrease and increase a value （acid-base response coefficient） of kaolinite particles, respectively. The T-O cleavage plays a dominant role in the breakage and cleavage of large kaolinite particles, and the E-E cleavage plays a more and more dominant role in the breakage and cleavage of smaller kaolinite particles, which is the main cause of electrokinetic characteristics of different sizes kaolinite particles in aqueous solutions.