Lipase-catalyzed optical resolution of R(-)-mandelic acid via RS-ethyl mandelate in non-aqueous media was studied.Lipase N435 was screened as the catalyst

and tert-butanol was used as the solvent.When lipase N435 was 2.5 g·L-1

RS-ethyl mandelate was 0.25 mol·L-1

water to RS-ethyl mandelate was 5∶1(molar ratio)

the reaction temperature was 40℃

the speed of agitation was 200 r·min-1

the R (-)-ethyl mandelate conversion could reach 41.6%

and enantiomeric excess (e.e.) was 84.0% after 24 h.Inhibition by the substrate and product was also investigated.A kinetic model was established by following the ordered bi-bi mechanism and quasi-steady state.Good agreement between experimental data and the simulation results was obtained.