Novel applications for organic acids

Chapter fourteen Novel applications for organic acids... 

The incomplete comprehension of mass transfer mechanisms in ED membrane systems is in all probability responsible for the difficult design of industrial plants and for their limited diffusion. For instance, in the food biotechnology sector ED applications are still in their infancy since quite a limited number of the novel processes studied so far in laboratory- and pilot-scales and reviewed here have been converted into industrial realities yet, except for the recovery of the sodium salt of unspecified organic acid from clarified fermentation broths, as well as amino and organic acids (Gillery et al., 2002). 

Although zwitterions are mainly considered for their novel ion conductive matrix in this chapter, they are being used as not only as solvents and catalysts for organic reactions [42] but also as organogelators [43]. Zwitterions have been screened as solvent/catalysts for several classical acid-promoted organic reactions such as the Fischer esterification, alcohol dehydrodimerization, and the pinacol/ benzopinacole rearrangement. The zwitterion containing an equimolar trifluoro-methane sulfonic acid is liquid at room temperature. Because they can work as solvent/catalysts, as shown in the reactions discussed in this chapter, zwitterionic liquids should open the door to a whole new area of applications. 

Cellulose can be esterifled with almost any organic acid [81,82,84], Whereas this is possible in principle with both alkyl chlorides and carboxylic anhydrides, commercial practice has focused on the anhydride option. Although many esters have been described in the literature, industrially manufactured organic esters are prepared only with aliphatic fatty acids with between 2 and 4 carbon atoms in length (i. e., acetates to butyrates, CA to CB). Exceptions are some mixed esters with phthalic acid, which are used for enteric coatings in pharmaceutical applications and a novel carboxymethyl cellulose acetate butyrate (CMCAB), which is used in water-borne coatings applications [81,84],... 

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