Synthesis And Properties Of Cardanol Betaine Amphoteric Surfactants

In this paper, the intermediate cardanol chlorohydrin ether was synthesised by cardanol,epichlorohydrin and the catalyst--tetrabutyl ammonium bromide, The product is then reacted with dimethylamine to form tertiary amine, finally, the surfactant was synthesised together with 3-chloro-2-hydroxy propyl sulfonate. This paper studies the performance of the product at:infrared spectrum, surface tension, interfacial tension, emulsification property, thermal stabilitys and the composite stabilizer with polyacrylamide.The experiments carried out on the basis of previous improvements: glycidyl ether as intermediate. This method has the following advantages: low reaction conditions, simple operation, high catalytic activity, convenient processing of intermediate, high conversion of tertiary amine, etc.FIR of the surfactant and the intermediate shows that all substances have characteristic absorption peaks of the target product, Initially, so we can draw the conclusion that they are target products.Designing orthogonal test according L9(4 3)factor levels for synthesis of tertiary amine.Optimum conditions are:n(cardanol chlorohydrin)/n(dimethylamine)/n(NaOH)=1/2.5/1.4,t=6h, T=40℃. 3replicates were tested under these conditions, conversion of tertiary amine is much more satisfactory, reaching 90%.Using spinning drop method to test the interfacial properties of surfactants,Experiments show that the surfactant has good performance. At the concentration of0.5~3.0g/L,it can maintain a good performance, interfacial tension reachiing10-4~10-3mN/m;The surfactant can meet with ultralow interfacial tension requirements both in high temperature(55~95℃)and high salt(32308~64616mg/L) conditions.Determiing the emulsifying properties of the surfactant through the watershed time method. Experiments show that single surfactant has poor properties, watershed time is short within 0.5~3.0g/Lconcentration range, about 35 s or so.By observing the changes of the interfacial tension during analoged formation(85℃)for 42 days, we can conclude the thermal stability of the surfactant. Experiments show that surfactant properties will be reduced over time, leading to an increase of the interfacial tension, however, the interfacial tension can still maitain10-3mN/m, enough for EOR.Adding polyacrylamide made it much more superior:Adding a certain amount(0.5~1.5g/L)of the polymer enables the interfacial tension reaches10-6~10-4mN/m; Adding polymer can effectively reduce the critical micelle concentration, without much effect on the equilibrium surface tension:cmc=2.75×10-4mol/L, γcmc=34.96mN/m in the condition of cpolymer=0.5g/L; cmc=1.38×10-4mol/L, γcmc=35.72mN/m in the condition of cpolymer= 1.5g/L;The emulsification performance is highly improved(about200~1200s)within the polymer concentration of 1.0~1.5g/L;the system is much more stable, besides, interfacial tension can reaches10-5~10-4mN/m.