Preparation method for a-type hemihydrate gypsum
(22) 02.11.2022
(43) 29.06.2023
(57) A preparation method for an a-type he-mihydrate gypsum, comprising the following steps: (1) enabling a desulfurized = gyp-
sum suspension and propionic acid to react at 120-140 C for 3-5 hours; (2) carrying out
solid-liquid separation, and carrying out vac-
uum drying at 40-80° C to obtain an a-type high-strength hemihydrate gypsum. In the present preparation method for the ci-type
high-strength hemihydrate gypsum, propionic acid is used as a crystal transfer agent, only three carboxyl groups are contained, the
distance between every two adjacent carboxyls is two C atoms, and no complex void
groups are contained. Thus, the a-type high-
strength gypsum tends to develop in the ra-
dial direction, a short-column-shaped a-type
high-strength gypsum crystal is obtained, the strength‚1IC of the a-type high-strength
gypsum is improved, and resource utilization
of the desulfurized gypsum is facilitated.
(71) Henan Polytechnic University, Henan 454000 (CN)
