Influence of the scaling inhibitor on the phase composition, morphology, and sedimentation properties of caco₃ deposits

We study the influence of OK-2 scaling inhibitor based on polyhexamethyleneguanidine hydrochloride on the morphology and phase composition of calcium carbonate. It is established that the presence of inhibitor in the solution leads to an increase in the sizes of crystals in the deposit and the predominance of needle structures in it. The aragonite and calcite phases are in excess in the deposits of calcium carbonate and the presence of inhibitor in the solution increases the amount of calcite by 21%. The revealed effects are caused by the adsorption of the inhibitor on carbonate deposits, which can be described by the Langmuir isotherm. The adsorption of the inhibitor leads to the recharging of the CaCO₃ surface and to the increase in the size of particles of the dispersed phase, which promotes its faster precipitation.