Abstract:

Alcohols extremely affect the formation of uniform colloidal particles in the hydrolysis of ferric ions for Fe(NO_3)_3-HNO_3 system. The affecting ability of the alcohols decreases by the order: 2-propanol, ethanol, t-butylalcohol, 1-propanol and n-butanol. The uniform colloidal particles could prepare in the aging solutions containing lower concentration of Fe(NO_3)_3 and higher concentration of HNO_3 in the presence of alcohols comparing with that in the absence of alcohols. The shapes and sizes of the particles formed depend not only on the concentrations of Fe(NO_3)_3 and HNO_3, but also the content of alcohols. In general, lower saturation of precipitating species favours the formation of spherical particles, and high saturation for the elliptic ones.

Key words: Alcohols, Hydrolysis, Supersaturation, Nucleation, Particle morphology