The Synthesis And Anti-foam Application For Modified Siloxane

Due to the anti-foam requirements of coke drum in delayed coking unit, this paper studied a new method to synthesize modified silicone oil of polyether ester, and had further application research with this kind of anti-foam agent in petrochemical oil. And particularly in terms of catalyst and raw materials, the development of innovative method were prepared.Firstly, the best foaming performance of coking products oil was determined in low temperature, and under this condition the performance of anti-foam agents was measured and some agents were selected according to the results. Conditions of best bubbling:ventilation velocity is 8ml/s, the ratio of coking diesel and wax is 9:1, temperature for 40℃.From the anti-foam performance and structure of polyether and ester base modified silicone oil, it could be conclused that two types of agents all had certain anti-foam performance, however, these properties still could not meet the requirements. By experiment of exploring new catalysts, new method was developed to synthesize modified silicone oil of polyether ester, which had good anti-foam property in coking products oil and reduced the cost. The conditions of synthesizing ester:the retio of acid and glycol was 1:1, reactive time was 8h, catalyst 3% and temperature for 115～120℃. The conditions of modifying silicone oil: D4:ester was 1:1.5, time and catalyst for auto polymerization of D4 were 2h and 0.06%, and active temperature for 140～145℃.