The invention discloses a preparation method of plate frame type poly(
aluminium chloride). The preparation method is characterized in that the plate frame type poly(
aluminium chloride) is prepared from the following raw materials in parts by weight: 100 parts of 30 percent
hydrochloride, 50-80 parts of
bauxite and 30-50 parts of
calcium aluminate powder, wherein in the
bauxite, the content of aluminum
oxide is not less than 30 percent, and the content of
ferric oxide is not larger than 4 percent; in the
calcium aluminate powder, the content of aluminum
oxide is not less than 50 percent, the content of
calcium oxide is 28-32 percent, and the content of
ferric oxide is 1-2.5 percent. The preparation method of the plate frame type poly(
aluminium chloride) comprises the following steps: diluting
hydrochloride by 19-26 percent, putting the
bauxite according to the proportion, raising the temperature by 40-80 DEG C, carrying out reaction for 10h, putting the calcium
aluminate powder, carrying out reaction for 1.5-2h at the temperature of 60-90 DEG C, and carrying out pressure
filtration with the pressure of a plate frame to be 10-20kg / mm<2> to obtain a finished product. The plate frame type poly(
aluminium chloride) prepared by using the preparation method is low in cost, simple in process and stable in product quality without limitation in using range.