The invention relates to a method for preparing 2-ethyl
anthraquinone with a one-
step method, in particular to a method for preparing the 2-ethyl
anthraquinone through a one-step reaction of
ethylbenzene and
phthalic anhydride under
catalysis of an alkali desilication modified Hbeta
molecular sieve, and aims to solve technical problems that the production technology is complex, a large amount of acid
wastewater is produced, equipment is corroded severely, catalysts cannot be recycled and continuity of the production process cannot be realized due to the fact that two homogeneous catalysts, namely,
anhydrous aluminum trichloride and concentrated
sulfuric acid, are used respectively when the 2-ethyl
anthraquinone is prepared through a two-step reaction of the
ethylbenzene and the
phthalic anhydride at present. The method comprises steps as follows: the
phthalic anhydride and the
ethylbenzene are evenly mixed, then the catalyst, namely, the alkali desilication modified Hbeta
molecular sieve, is added, the mixture reacts at the
reaction temperature of 170-230 DEG C for 1.2-5 h, a
solid-liquid mixture is obtained, the
solid catalyst, namely, the alkali desilication modified Hbeta
molecular sieve, is separated after cooling, and the 2-ethyl anthraquinone is obtained. The method is mild in reaction condition, high in product yield and high in phthalic anhydride conversion rate.