REVERSIBLE MICROCAPSULE FILTER CAKE

摘要

The invention teaches a method of efficiently dewatering a microcapsule slurry to form a water re-suspendable filter cake of microcapsules. The process comprises providing an aqueous slurry of microcapsules dispersed in an aqueous solution; adding an agglomeration agent and dispersing the agglomeration agent into the aqueous slurry; adjusting the pH to a pH level sufficient to agglomerate the dispersed microcapsules; and filtering the aqueous slurry of microcapsules by gravity, vacuum or pressure filtration to thereby form a filter cake of dewatered microcapsules. The agglomeration agent is sodium polyphosphate, sodium tetrapolyphosphate, sodium hexametaphosphate, and/or sodium tripolyphosphate; or with anionic microcapsules or coatings even alkaline earth metal salts such as magnesium chloride, calcium chloride or barium chloride, or even aluminum salt such as aluminum chloride.

主权项

1. A method of efficiently dewatering a microcapsule slurry to form a water re-suspendable filter cake of microcapsules comprising:
providing an aqueous slurry of microcapsules dispersed in an aqueous solution; adding an agglomeration agent and dispersing the agglomeration agent into the aqueous slurry; adjusting the pH to a pH level sufficient to agglomerate the dispersed microcapsules; filtering the aqueous slurry of microcapsules by gravity, vacuum, centrifuying or pressure filtration to form a filter cake of dewatered microcapsules