Abstract: SO₄^2-/Hangjin 2^# clay solid acid catalyst was prepared by impregnation method using activated clay（sulfuric acid- treated Hangjin 2^# clay） as supporter.Taking the esterifications of acetic acid and n-butanol as probe reactions，the effects of Hangjin 2^# clay treatment conditions and solid acid catalyst preparation conditions on the esterification reaction activity were investigated.And the stability of catalyst was initially studied.Results showed that solid acid catalyst prepared from cheap Hangjin 2^# clay performed high activity under suitable conditions，which was the base for its industrial application.

Key words: Hangjin 2^# clay, solid acid catalyst, esterification reaction