Patent ID: 6268530
Filing Date: 2001-07-31
Classification: C07C,C07D

Abstract:
A process to separate linear 5-formylvaleric acid from a mixture of 5- and 3- and/or 4-branched formylvaleric acids, comprising performing the separation by fractional extraction with two immiscible solvents, wherein one solvent is an aqueous solvent and the other solvent is an organic solvent which has the following characteristics:-2.8<A<-0.2 and 0.14<B<2.39or1.7<A<4.0 and -4.0<B<-1.64in which, A and B are:A = 0.23 * (T.sub.B - 138.54)/62.36 + 0.24 * (.rho. - 935.64)/184.82 + 0.0554 * (n.sub.d - 1.4370)/0.0635 + 0.3916 * (.epsilon..sub.r - 15.02)/18.66 + 0.1208 * (.delta..sub.d - 16.68)/1.738 + 0.4135 * (.delta..sub.p - 6.11)/5.16 + 0.3462 * (.delta..sub.h - 8.05)/6.97 + 0.4177 * (.delta. - 20.69)/5.087 + 0.3370 * (.mu. - 1.73)/1.20 + 0.3723 * (E.sub.T(30) - 41.14)/7.61 B = -0.3009 * (T.sub.B - 138.54)/62.36 - 0.3882 * (.rho. - 935.64)/184.82 - 0.5914 * (n.sub.d - 1.470)/0.0635 + 0.1225 * (.epsilon..sub.r - 15.02)/18.66 + 0.5506 * (.delta..sub.d - 16.68)/1.738 + 0.0970 * (.delta..sub.p - 6.11)/5.16 + 0.2291 * (.delta..sub.h - 8.05)/6.97 + 0.0583 * (.delta. - 20.69)/5.087 + 0.0381 * (.mu. - 1.73)/1.20 + 0.1550 * (E.sub.T(30) - 41.14)/7.61in which T.sub.B represents the normal boiling point (.degree. C.), .rho. the density measured at 20.degree. C. (kg/m.sup.3), n.sub.d the refractive index (-), .di-elect cons..sub.r the di-electric constant measured at 20.degree. C. (-), .delta..sub.d the Hansen solubility parameter of dispersion (Mpa.sup.1/2), .delta..sub.p the Hansen solubility parameter of polarity (Mpa.sup.1/2), .delta..sup.h the Hansen solubility parameter of hydrogen bonding (Mpa.sup.1/2), .delta. the Scatchard-Hildebrand Volubility parameter (Mpa.sup.1/2), .mu. the dipole moment (Debey) and E.sub.T(30) the Lewis donor/acceptor property (kcal/mol) or the organic solvent is an ether or an ester with 2 to 10 carbon atoms represented by the following formulaR.sup.1 --O--R.sup.2 (7)##STR2##in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently an alkyl or aryl group with 1 to 7 carbon atoms and in which R.sup.1 and R.sup.2 is optionally a divalent group.