Production of aluminum sec-butoxide aerosol (a precursor to alumina powder) by vapor condensation on seed nuclei in laminar flows is studied theoretically. The effects of process parameters(condenser inlet and wall temperature, carrier gas flow rate) and condenser configuration (tubular and annular) on product aerosol characteristics (average size and polydispersity) and the condenserlength required for complete vapor condensation are examined. Operation with large Lewis numbers (Le > 2) results in nearly monodisperse aerosol regardless of the carrier gas or condenser configuration provided that the condenser length is sufficient to condense out most of the inlet vapor and that homogeneous nucleation is suppressed by the seed nuclei. © 1988, American Chemical Society. All rights reserved.