Process for making triphenylboron-pyridine compound
AssigneeInvista North America S.A.R.L.
InventorJohn J. Ostermaier
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Abstract
A process for improving the recovery of solid triphenylboron-pyridine compound (TPBP), while retaining desirable particle characteristics comprises the addition of an acid to neutralize at least a portion of the alkali contained in the aqueous mother liquor. By adjusting the pH of the product slurry to between about 8.5 and about 12, it is possible to increase product recovery by more than 10%, while maintaining desirable particle characteristics.
Claims21
A process for producing triphenylboron-pyridine (TPBP) comprising generally spherical solid particles which comprises:
- (A) providing a product slurry comprising solid TPBP particles in an aqueous mother liquor in a vigorously agitated reaction zone;
- (B) separately feeding into said vigorously agitated reaction zone (i) a stream of pyridine and (ii) a stream comprising a solution of an alkali hydroxide adduct of triphenylboron (TPBA), whereby the total concentration of TPBA in the combined feed streams is in the range of from about 1 wt % to about 6 wt %, to form additional TPBP in the product slurry;
- (C) adding to the product slurry a sufficient amount of acid to adjust pH of the product slurry to a value of about 8.5 to about 12.0;
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- (D) removing a product stream from said reaction zone at such a rate that the volume of said product slurry in the reaction zone remains substantially constant, and the concentration of solid TPBP in the product slurry is maintained at a value of less than about 8 wt %.
A process for producing triphenylboron-pyridine (TPBP) which comprises:
- (A) separately feeding into a reaction zone (i) a stream comprising pyridine and (ii) a stream comprising a solution of an alkali hydroxide adduct of triphenylboron (TPBA) to form a product slurry comprising TPBP in an aqueous mother liquor;
- (B) adding to the reaction zone a sufficient amount of acid to adjust pH of the product slurry to a value of about 8.5 to about 12.0;
- (C) removing a product stream from said reaction zone which includes the TPBP particles.
Dependencies are inferred from the claim text.