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Vaterite synthesis via gas – liquid route under controlled pH conditions / Ion Udrea in Industrial & engineering chemistry research, Vol. 51 N° 24 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 24 (Juin 2012) Titre : Vaterite synthesis via gas – liquid route under controlled pH conditions Type de document : texte imprimé Auteurs : Ion Udrea, Auteur ; Constantin Capat, Auteur ; Elena A. Olaru, Auteur Année de publication : 2012 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Gas  liquid  pH Résumé : The purpose of this work was to obtain precipitated calcium carbonate (PCC) particles in polymorphic form of vaterite via gas―liquid route in controlled pH conditions. The effect of CO2 concentration (12.5―100%), feed gas (CO2―air) flow rate, pH, and conductivity of solution upon the PCC particles properties was studied. On the basis of the experimental data, the main factors leading to vaterite formation as major product were established. It was found that the buffer solution has a decisive role in determining polymorphic phase of PCC while CO2 concentration and feed gas flow rate have no significant influence. It was demonstrated that spherical vaterite particles of high purity can be produced under controlled reaction conditions. Also, some considerations on the mechanism of carbonation process were formulated. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202221m [article] Vaterite synthesis via gas – liquid route under controlled pH conditions [texte imprimé] / Ion Udrea, Auteur ; Constantin Capat, Auteur ; Elena A. Olaru, Auteur . - 2012. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 24 (Juin 2012) Mots-clés : Gas  liquid  pH Résumé : The purpose of this work was to obtain precipitated calcium carbonate (PCC) particles in polymorphic form of vaterite via gas―liquid route in controlled pH conditions. The effect of CO2 concentration (12.5―100%), feed gas (CO2―air) flow rate, pH, and conductivity of solution upon the PCC particles properties was studied. On the basis of the experimental data, the main factors leading to vaterite formation as major product were established. It was found that the buffer solution has a decisive role in determining polymorphic phase of PCC while CO2 concentration and feed gas flow rate have no significant influence. It was demonstrated that spherical vaterite particles of high purity can be produced under controlled reaction conditions. Also, some considerations on the mechanism of carbonation process were formulated. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202221m