The invention belongs to the field of
hydrometallurgy and particularly relates to a
vanadium pentoxide preparation method. The preparation method comprises the following steps that (a) the temperature of acidic
vanadium liquid rises from normal temperature to 65-75 DEG C in the preheating process of a
vanadium precipitation process by using a
static mixer pipe and utilizing steam heat exchange; (b) the acidic vanadium liquid subjected to heat exchange is added into an
ammonium tank,
ammonium sulfate is added, and stirring is performed to obtain mixed liquid; (c) the mixed liquid is added into a
sedimentation tank, stirring is performed, a pH value is regulated to be 1.5-2, and
steam heating is performed to reach 90 DEG C to boiling so as to obtain an
ammonium poly-
vanadate solution; (d) precipitate obtained after the ammonium poly-
vanadate solution precipitates is washed, dried and calcinated to obtain vanadium
pentoxide. The flowing state of the acidic vanadium liquid in the
pipe is changed by utilizing a mixing unit body fixed in the
static mixer pipe, the formation of a laminar flow bottom layer is inhibited to enable the acidic vanadium liquid to rapidly disperse in the pipe, the temperature distribution of all parts of the solution tends to be uniform, the formation of a scale layer is retarded, and the production efficiency of the vanadium
pentoxide is improved.