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An ion exchange resin. Strong acid cation exchange resin styrene cation exchange resin; weak anion exchange resin refers to the use of alkaline styrene anion exchange resin.
An ion exchange resin. Strong acid cation exchange resin styrene cation exchange resin; weak anion exchange resin refers to the use of alkaline styrene anion exchange resin.
Production process: The modulus of 3.5 sodium silicate solution diluted with water adjusted to contain SiO24%, Na201.15%; the solution through a cation exchange resin packed flash exchange column, was contained SIO23.6%, NA200.005% , SiO2 / Na2O molar ratio of 703, PH value of 2.5 dilute solution of silicic acid gel.
Ion exchange is an equilibrium reaction, the reaction process is: When the Na + silicic acid-containing solution through the exchange resin refers to Ma + replaces the cation exchange resin in the H +. So the water glass has been removed NAa +, H + cation and silicon ions with sodium silicate in the sol SiO3 generate a dilute solution of active outflow.
By mass of ion-exchanged silica sol with the following factors: the height of the degree of resin regeneration, the balance of properties, the resin flows into the depth of the ion size. The dilute silica sol by cation exchange column depth and then weakly basic anion exchange resin through the column, liquid is removed anions CL-, in order to achieve a more stable state. In exchange column flow out of the dilute silica gel thick deep cross low, need to be concentrated, in order to prevent the concentrated gel, must be quickly added stabilizer before concentrated. Often stabilizer is MOH (M is L, Na, K, Rb, Cs, NH4.NH2 etc.) The amount of stabilizer should be appropriate, if less than 1% of the number of moles of SiO2 stabilizing effect is difficult; if more than 5% The purity of the products will be reduced. 5kg take the silica sol with 10% NAOH solution was adjusted PH value to 78. Take 900g adjust fluid injection pressure reducer in the letter were true it concentrated under reduced pressure. And in order to maintain a constant level in the container principle, slowly add the remaining liquid 4100g adjustment. Concentrate temperature was maintained 78 ℃, was finally obtained 900g containing SiO220%, Na200.33% PH 9.6 silica sol having an average particle diameter of about 16mum.
After ion exchange the ion exchange resin, the exchange capacity has been lost. Required was washed with dilute hydrochloric acid, HCL in H9 + substitution on the resin Na +. Leaving the active groups oxide ion exchange resin, the resin regeneration, recovery exchange capacity. PH value and ion exchange resin regeneration means must be rinsed with distilled water to a predetermined date, prepare for the next use.
Technical performance sol: SiO2 content of 30% to 20% (in terms H2SiO3 content> 26%) 70% 80% moisture content of 0.4% proportion 1.141.21Na2O 0.5% Viscosity (Tu 4) 10.9S can be stored for one year