DEMULSIFICATION OF NATURAL WATER-IN-OIL EMULSIONS WITH COMPOSITIONAL MIXTURES BASED ON SURFACTANTS

The paper considers the stability of crude oil emulsions in the presence of aqueous solutions of polymers and surfactants and their mixtures. Surfactants of different nature (anionics, cationics and nonionics - sodium dodecylbenzenesulfonates (sulphanol), cetyltrimethylammonium bromide (CTAB), ethoxylated isooctylphenol (OP-10), respectively) and watersoluble industrial polymers such as polyethylenglicol (PEG), carboxymethylcellulose (NaCMC) were used for preparation of demulsifying compositions. The behavior of the compositional mixtures at the different interfaces was studied. The compositions studied have a high surface activity (surface tension decreases till 3 mJ/m(2) at the water/oil interface). The demulsifying action of the compositional mixtures was researched. The most effective dewatering compositions were obtained on the base of CTAB and NaCMC at ratio of 1:1. The amount of separated water was equal to 91,95 % after 105 min at 60 degrees C. In addition, the combined action of thermochemical processing and centrifuging showed the increase of dewatering degree of water-in-oil emulsions under action of CTAB/NaCMC mixture (V=97,95 %).