Removal of microgel

Chauveteau and Kohler (1980) also proposed a microgel test on the solutions which have been prepared by the above procedure. In this test, the solution is pumped at a slow constant rate through a 3-fim filter and the upstream pressure is monitored using a small water manometer. If the pressure remains low and constant with time then no microgel is present, but if a gradual rise in pressure is observed then this indicates the presence of microgel in the solution. 

Although the original microgel removal procedure was applied to xanthan, it can also be used for HPAM and other synthetic polymers. It is also informative to monitor the polymer concentration before and after different filtration procedures in other to assess how much material is lost in various stages. If excessive amounts of filter blocking occur, this may cause effective reduction in filter pore size and a considerable amount of molecular material—as opposed to debris and microgel—may be removed. 

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