The invention discloses a new process for preparing p-
xylylene dichloride by adopting novel reaction equipment. The novel reaction equipment comprises a chlorinator, a gas-liquid separator, a crystallizer and the like. The process for preparing the p-
xylylene dichloride by adopting the novel reaction equipment comprises the following steps: (1) reaction; and (2) separation by
crystallization. Theprocess has the beneficial effects that by adopting the novel reaction equipment, p-
xylene and
chlorine gas can be thoroughly and uniformly mixed, and excessive chlorination caused by high local
chlorine concentration is avoided; chlorination is carried out in three stages, a reactant proportioning ratio of each stage is accurately controlled, the single-pass conversion ratio of p-
xylene is higherthan 96%, the total selectivity of p-
xylylene dichloride and p-methyl
benzyl chloride in a chlorination solution reaches up to 98%, and the content of p-xylylene dichloride reaches up to 70% or more;a used
LED lamp, as a
light source, for initiating reaction is proper in
wavelength and is high in initiating efficiency, the
reaction temperature can be greatly lowered, and side reactions can be effectively reduced; and the chlorination solution is low in
impurity content, the product is not required to be purified by a vacuum rectification process, and the product with the content of 99% or more can be obtained by once simple
crystallization.