无机盐对O/W乳状液可逆转相和稳定性的影响

摘要

This paper studied the effects of inorganic salts on the phase and stability of O/W emulsion by observing the sedimentation stability property,emulsion-breaking voltage,electrical conductivity and microstructures.The results showed that multivalent metal salts led to the demulsification or phase inversion of the O/W emulsion.The ability of multivalent metal salts that impel emulsion phase inversion to happen was arranged in the sequence of CrCl3 ＞ MgCl2 ＞ CaCl2 ＞ SrCl2 ＞ BaCl2.But FeCl3 only triggered demulsification not phase inversion.And the excessive concentration of metal salt reduced the stability of emulsion.OH-or acid radical ions can remove the effects of multivalent metal ions on O/W emulsion.The precipitates were formed by the reaction of Na2CO3,NaOH,Na2SiO3,and Na3PO4 with Cr3+ leading to W/O emulsion inverting to O/W type.On the contrary,Na2SO4,H2SO4 and H3PO4 can not result in emulsion reversible inversion.%从乳状液的沉降稳定性、破乳电压、电导率和微观形态等几个方面,系统地研究了无机盐对十二烷基苯磺酸钠稳定的O/W乳状液相态和稳定性的影响.结果表明,高价金属盐会导致乳状液破乳或转相,其中FeCl3只能导致乳状液破乳,不能引发转相,其他金属盐引发乳状液转相的能力依次为CrCl3＞ MgCl2＞CaCl2＞ SrCl2＞ BaCl2;金属盐浓度过高时不利于转相后的乳状液的稳定;OH-或部分酸根可以消除高价金属离子对乳状液的影响,Na2CO3、NaOH、Na2SiO3和Na3PO4可以与Cr3+反应生成不溶物,使W/O乳状液再次转相为O/W型,而Na2SO4、H2SO4和H3PO4则不能使乳状液发生逆转相.