石油磺酸钠/SDBS协同稳定的盐度响应性可逆乳状液

乳状液可逆转相技术在油田作业中发挥了重要作用,温度、pH、光照等因素响应的可逆乳化技术易受环境限制,盐度响应的可逆乳状液逐渐成为研究热点。通过复配石油磺酸钠和十二烷基苯磺酸钠,得到了一种盐度响应性可逆乳化剂。以乳状液的析水(油)率、电导率、破乳电压、微观形态作为评价指标,研究了CrCl3和Na2SiO3对乳状液类型的影响,并探究了复配比例与乳状液稳定性的关系。结果显示,CrCl3可以使乳状液由O/W型转相为W/O型,Na2SiO3可以使已转相的乳状液发生逆转相；且随着石油磺酸钠复配比例的提高,乳状液在可逆转相的各个阶段的稳定性均增强,当其复配比例达到25wt%时,乳状液不再逆转相。石油磺酸钠和SDBS的复配比为4:16时形成的乳状液容易在无机盐的作用下发生可逆转相,且稳定性最好。

Salt Concentration-Responsive Reversible Invert Emulsions Stabilized by SPS/SDBS

The phase reversible inversion technique of emulsion plays the important role in the oilfield operations. Temperature-responsive, pH-responsive, and light-responsive reversible inversion technique are easily limited by the environment. Salt concentration-responsive reversible invert emulsion gradually becomes research hotspot. A kind of salt concentration-responsive reversible emulsifier was developed by compounding SDBS and SPS. Water/oil separation rate, electrical conductivity, emulsion-breaking voltage and microstructures were used as the indexes to analyze effects of CrCl3 and Na2SiO3 on the type of emulsions and relations of compounded proportions and stability. Results showed that the type of emulsions from O/W inverted to W/O by adding CrCl3. And Na2SiO3 can result in emulsions reversion. Emulsions became more stable in all stages of reversible inversion with the percentage of SPS growth. When the percentage of SPS reached 25%, emulsions will not revert. The emulsion stabilized by compounded surfactant composed of 20wt% and 80wt% SDBS was easily realized reversible inversion under the effect of inorganic salts and was the most stable.