Mn. Ramsis et al., THE KINETICS OF THE CRYSTALLIZATION OF BARIUM CHROMATE IN PRESENCE OFPOLYPHOSPHATE AND PHOSPHONATES, Monatshefte fuer Chemie, 127(11), 1996, pp. 1099-1108
The inhibiting effect of polyphosphate and phosphonates on the crystal
lization of barium chromate for both seeded and unseeded systems has b
een investigated using the changes in ionic conductivity of the lattic
e ions in supersaturated solutions containing stoichiometric concentra
tions of barium and chromate at 298 K. The inhibitors studied are sodi
um tripolyphosphate (STP), ethylenediaminetetramethylenephosphonic aci
d (ENTMP), and 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP). The e
ffect of these inhibitors on the growth of crystals has been studied a
t several inhibitor concentrations. The influence of these additives o
n barium chromate crystallization could be interpreted in terms of a L
angmuir type adsorption isotherm. The crystallization retarding effect
due to inhibitors is in the order HEDP > STP > ENTMP. The inhibitors
studied can be used as effective compounds for scale formation control
.