Succinic Acid Ester Sulfonate Gemini Type Surfactants Synthesis And Performance Research

In this paper, Gemini-12, Gemini-14, Gemini-16and Gemini-18were synthesized using1-dodecanol,1-tetradecanol,1-hexadecanol,1-octadecanol, maleic anhydride and ethyleneglycol as starting materials. The structure of the target compounds were identified by IR and1HNMR, and Gemini-14, Gemini-16and Gemini-18are new compounds.Activated carbon supported heteropoly acid was used as the green catalyst fordouble-esterification reaction which includes phospho-wolframic acid, phosphato-molybdicacid and silicotungstic acid. Comparing the effect of catalysis on the synthesis of Gemini-12,phospho-wolframic acid was the optimal catalytic，furthermore it was used in the synthesis ofGemini-14, Gemini-16and Gemini-18, and the catalytic effect were also significant.The best conditions of single esterification, double-esterification and sulfonation wereobtained by the orthogonal experiment with the synthesis of Gemini-12, whereafter they wereused for the syntheses of Gemini-14, Gemini-16and Gemini-18，the esterification rate weremore than85%and sulfonatedrate were more than90%.The surface tension, Krafft temperature, foaming ability and emulsifiability of theGemini surfactants were tested. It can be found that the Gemini surfactants all have lowcritical micelle concentration (cmc). The cmc of Gemini-14was20.11mN/m, and it was themost active surfactant. In addition, they also emerge lower Krafft temperature,strongeremulsifying and better foaming ability, which can be used in different areas. Moreover, therelations of structure and the performance of four compounds were discussed.The IFT of the Gemini-n of Liaohe Oilfield was tested. The results show that a singlecomponent is not obvious in reducing the IFT. According to the formulation principle of thesurfactant, the optimal proportion of the mixtures of Gemini surfactants and SDBS was sievedby orthogonal experiments so that the obtained IFT was lower. The results showed that SDBShas a good synergistic effect with Gemini surfactants, and the optimal mixture even couldreduce the IFT to10-5mN/m.The optimal mixtures were used for preliminarily oil sands separation experiments, theresidues of oil in sand was1.62%，1.43%，1.75%of the Gemini-12, Gemini-14andGemini-16mixtures, respectively, which have reached the national standards.