Study On Synthesis And Application Of Silica-Aluminum Microparticle Retention And Drainage Agent

Since the beginning of 90's years in the 20 century, Microparticle retention and drainage system have had wide development in both research and application field because its excellence capabilities. Presently, the development of microparticle retention and drainage system are main embodiment in the research and exploitation of new microparticle agent. The article mainly discussed these topics: Synthesizing a new type silica-aluminum microparticle retention and drainage agent; Testing the performance of retention and drainage in papermaking by using dynamic drainage jar. Major experimental results are as follow.The perfect processing condition of silica-aluminum micropartile synthesis was: The concentration of sodium silicate is 0.15%,Temprature of reaction is 25-30 C,pH value is 7.5-9.5.Time of reaction is about 1.5 hours.Silica-aluminum microparticle is a type of super little spherical paniculate with high surface area. Diameter is about 5-10nm, surface area is about 615 m2/g.The retention and drainage performance of silica-aluminum microparticle system is more better than two-component system comprised with CS and CPAM. The perfect dosage of each aid is: CS1%, CPAM0.02%, silica-aluminum microparticle 0.1%~0.3%.In CPAM/ silica-aluminum microparticle system, When CPAM is added in high shearing strength, the performance of retention and drainage are more better than it is added in low shearing strength. From comparison of the performances of retention and drainage, We found out silica-aluminum microparticle system is better than routine CS/CPAM system or CS/ Silica-aluminum microparticle system. The retention actions of both GCC and talcum powder is excellent.Silica-aluminum gel has the same performance of retention and drainage as Silica-aluminum sol. The difference lies in that the dosage of Silica-aluminum gel is 5%,while the Silica-aluminum sol is 0.1% when they achieve the same effect of retention and drainage. Both gel particle and gel filtrate have the abilities of retention and drainage, while gel filtrate is better than gel particle.Comparing the performance of retention and drainage, Adding CPAM first is better than adding silica-aluminum microparticle first. Silica-aluminum microparticle system are more powerful for resisting shearing strength, and it can be applied with abroad range of pH value.It is necessary to make it stabilization in the end of synthesis to resist producing gel; Theaction of retention and drainage will not change when Silica-aluminum microparticle is reserved less than two month.Silica-aluminum microparticle system won't affect the physical performance of paper when it enhances the retention efficiency.Silica-aluminum microparticle has no evident effect on AKD sizing. The sizing effect will be reduced when the dosage of AKD is less, while the dosage of silica-aluminum microparticle is overfull. On the contrary, AKD sizing effect will be enhanced when the dosage of AKD reaches some value, while the dosage of silica-aluminum microparticle is less than 0.1%.Silica-aluminum microparticle system comparing with bentonite system, It turns out the dosage of silica-aluminum microparticle is less than bentonite, but comparing with the performance of retention, the former is better than the later. The performance of hand sheet is superior too.