Appeal No. 2001-0697 Page 3
Application No. 09/125,033
Background
Carboxylic acids, such as lactic acid, are commonly produced by
fermentation of a carbohydrate-containing substrate by microorganisms. See the
specification, pages 1-3. As the desired carboxylic acids build up, however, they
acidify the medium and inhibit the activity of the fermenting microorganisms.
Therefore, a base is added to maintaining the pH at an optimal level. “More
concentrated medium resulting from fermentation is obtained but said medium
contains the salt of the acid rather than the free acid.” Id., page 1. Typically, a
strong mineral acid is then added to displace the carboxylic acid from the salt
and the desired carboxylic acid is purified by esterification and distillation. “The
purified ester can then be used as such or be hydrolysed to recover pure lactic
acid.” Id., page 2.
The specification discloses a process of producing lactic acid esters or
amides that eliminates the need to use a strong mineral acid to convert the
carboxylic acid salt to free carboxylic acid. The disclosed process begins with a
fermentation medium containing the sodium or calcium salt of a carboxylic acid.
This medium is combined with an organic compound containing either a hydroxyl
group (to form an ester) or an amine group (to form an amide) and CO2. The
CO2 is disclosed to displace the sodium or calcium from the carboxylic acid salt,
forming sodium or calcium carbonate and/or bicarbonate, and allowing the
carboxylic acid to react with the organic group to form the desired product, the
carboxylic acid ester or amide. See the specification, pages 4-5 (“The present
Page: Previous 1 2 3 4 5 6 7 8 9 10 Next
Last modified: November 3, 2007