Crystal growth of aragonite and calcite in presence of citric acid, DTPA, EDTA and pyromellitic acid
2005 (English)In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 282, no 2, 359-369 p.Article in journal (Refereed) Published
The influence of four calcium complexing substances. i.e., citric acid (CIT). diethylenetriaminepentaacetic acid (DTPA), ethylenedi- aminetetraacetic acid (EDTA) and pyromellitic acid (PMA), oil the crystal growth rate of the calcium carbonate polymorphs aragonite and calcite has been studied. Using a seeded constant supersaturation method supersaturation was maintained at 4 by keeping a constant pH of 8.5 through addition of sodium carbonate and calcium chloride solutions. The unique composition of each solution was calculated using chemical speciation. The growth rate was interpreted in terms of an overall growth rate. For both calcite and aragonite, the crystal growth rate is significantly reduced in the presence of the calcium complexing substances. The growth retarding effect depends on both the concentration and the polymorph. The relative crystal growth rate was correlated to the total complexing agent concentration using a Langmuir adsorption approach. Aragonite appeared fully covered for lower total concentrations than calcite. Furthermore, CIT very efficiently blocked aragonite growth contrary to what was observed for calcite. This is thought to be related to certain distinct features of the dominant aragonite crystal faces compared to the dominant calcite faces.
Place, publisher, year, edition, pages
2005. Vol. 282, no 2, 359-369 p.
crystal growth, calcium carbonate, precipitation, polyfunctional o-ligands, caco3 polymorphs calcite, dissolution kinetics, aqueous-solution, carbonate, inhibition, crystallization, morphology, phosphate, precipitation
IdentifiersURN: urn:nbn:se:kth:diva-14448DOI: 10.1016/j.jcis.2004.03.029ISI: 000226178700013ScopusID: 2-s2.0-10044275500OAI: oai:DiVA.org:kth-14448DiVA: diva2:332489
QC 201005252010-08-052010-08-05Bibliographically approved