Process for preparing paste-extruded sulfonamide compositions

摘要

Disclosed herein are paste-extruded sulfonamide herbicide compositions having improved spray equipment clean-out properties that are made by preparing a mixture comprising a sulfonamide herbicide free acid, at least about 50 equivalent % of an inorganic base relative to the sulfonamide herbicide free acid and sufficient water to form an extrudable paste, extruding the mixture to form an extrudate, and drying the extrudate. Particularly disclosed is a process for preparing a paste-extruded sulfonamide herbicide composition comprising (a) preparing a mixture comprising: (i) from 2 to 90% by weight on a water-free basis of one or more active ingredients comprising at least one sulfonamide herbicide free acid; (ii) from 0 to 95% by weight on a water-free basis of one or more additives selected from the group consisting of wetting agents, dispersants, lubricants, anticaking agents, chemical stabilizers and diluents; and (iii) at least about 50 equivalent % of base selected from inorganic base equivalents having conjugate acid pKas at least 2.1 units greater than the highest pKa of the sulfonamide herbicide free acid component; the sum of the weight percents of all the ingredients in the mixture totalling 100% on a water-free basis; and (iv) sufficient water to make the mixture an extrudable paste; (b) extruding the mixture prepared in (a) through a die or screen to form extrudate; and (c) drying the extrudate.