Gallium(III) sulfate hydrate is used in the preparation of other gallium compounds such as gallium oxide. It is supported on silica gel act as a solid acid catalyst, which is employed as a heterogeneous catalyst for the esterification of p-hydroxybenzoic acid and heptanol to give n-heptyl p-hydroxybenzoate. On reacting with strong acid cation ion exchange resin, it exhibits excellent catalytic activity, which is used for synthesizing amyl hexanoate.