Sodium Hydroxide → Aminopyralid

In a 3-liter (L) beaker was added 2000 grams (g) of hot water, 115.1 g of 50 percent by weight NaOH, and 200 g of wet 4-amino-3,5,6-trichloropyridine-2-carboxylic acid (79.4 percent). The solution was stirred for 30 minutes (min), filtered through a paper filter, and transferred to a 5-L feed/recirculation tank. This solution weighed 2315 g and contained 6.8 percent 4-amino-3,5,6-trichloropyridine-2-carboxylic acid. This feed was recirculated at a rate of about 9.46 L/min and a temperature of 30° C. through an undivided electrochemical cell having a Hastelloy C anode (15 cm×4 cm) and an expanded silver mesh cathode (15 cm ×4 cm). After normal anodization at +0.7 volts (v), the polarity of the cell was reversed and the electrolysis was started. The cathode working potential was controlled at −1.1 to −1.4 v relative to an Ag/AgCl (3.0 M Cl−) reference electrode. The reference electrode was physically located directly behind the silver cathode and connected electrically with an aqueous salt bridge. While recirculating the feed, a solution of 50 percent NaOH was slowly pumped into the recirculation tank to maintain the NaOH concentration at a 1.5 to 2.0 percent excess. The current ranged from 1.0 to 5.2 amps.

1. filtrationfiltered through a paper
2. filtrationfilter
3. customa temperature of 30° C.
4. temperatureto maintain
5. concentrationthe NaOH concentration at a 1.5 to 2.0 percent excess

ORDレコード

ord-0d69f0b424754eed9285f8d855717187

出典データセット

uspto-grants-2002_03

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06352635B1