Search
Filters
Close

Save 20% on select titles with code HIDDEN24 - Shop The Sale Now

07051 KINETICS OF CaCO3 PRECIPITATION IN THE PRESENCE OF SHMP

Product Number: 51300-07051-SG
ISBN: 07051 2007 CP
Author: David Hasson and Andrei Cornel
Publication Date: 2007
$0.00
$20.00
$20.00
The present work examines the kinetics of CaCO3 precipitation in a continuous stirred tank vessel in the presence of the inhibiting additive sodium hexametaphosphate (SHMP). The degree of CaCO3 precipitation and the degree of SHMP adsorption on the crystallizing particles were both measured in a series of experiments performed at the same initial supersaturation level. The parameters varied were the initial SHMP concentration and the residence time in the precipitation vessel. Variation of the SHMP dosage level gave the anticipated trend of a decrease in the degree of CaCO3 precipitation with an increase in inhibitor concentration. However, unexpectedly, at all SHMP dosage levels, the degree of CaCO3 precipitation was found to diminish at increasing residence times. The rate of SHMP adsorption on the crystallizing CaCO3 particles was found to vary inversely with the square root of residence time. This result suggests that adsorption of the SHMP on crystallizing CaCO3 particles is a slow, diffusion-controlled process. Precipitation is increasingly inhibited as the level of adsorbed SHMP increases at the augmented residence time. A diffusion-controlled adsorption model enabled successful correlation of all kinetic data.
The present work examines the kinetics of CaCO3 precipitation in a continuous stirred tank vessel in the presence of the inhibiting additive sodium hexametaphosphate (SHMP). The degree of CaCO3 precipitation and the degree of SHMP adsorption on the crystallizing particles were both measured in a series of experiments performed at the same initial supersaturation level. The parameters varied were the initial SHMP concentration and the residence time in the precipitation vessel. Variation of the SHMP dosage level gave the anticipated trend of a decrease in the degree of CaCO3 precipitation with an increase in inhibitor concentration. However, unexpectedly, at all SHMP dosage levels, the degree of CaCO3 precipitation was found to diminish at increasing residence times. The rate of SHMP adsorption on the crystallizing CaCO3 particles was found to vary inversely with the square root of residence time. This result suggests that adsorption of the SHMP on crystallizing CaCO3 particles is a slow, diffusion-controlled process. Precipitation is increasingly inhibited as the level of adsorbed SHMP increases at the augmented residence time. A diffusion-controlled adsorption model enabled successful correlation of all kinetic data.
Product tags
Also Purchased
Picture for 07041 STRAY CURRENT CONTROL BY A NEW APPROACH BASED ON TRUE POTENTIAL MONITORING
Available for download

07041 STRAY CURRENT CONTROL BY A NEW APPROACH BASED ON TRUE POTENTIAL MONITORING

Product Number: 51300-07041-SG
ISBN: 07041 2007 CP
Author: L. Lazzari, M. Ormellese, F. Duranti, P. Fabbri, Politecnico di Milano
Publication Date: 2007
$20.00
Picture for 07044 FAILURE OF ABOVE GROUND STORAGE TANKS
Available for download

07044 FAILURE OF ABOVE GROUND STORAGE TANKS

Product Number: 51300-07044-SG
ISBN: 07044 2007 CP
Author: Mohammed. Javeed Shaikh and Zain. Khadir Muhideen
Publication Date: 2007
$20.00
Picture for 07035 Technical Considerations on the Use of the 100mV Cathodic Polarization Criterion
Available for download

07035 Technical Considerations on the Use of the 100mV Cathodic Polarization Criterion

Product Number: 51300-07035-SG
ISBN: 07035 2007 CP
Author: R.A.Gummow and P.Eng
Publication Date: 2007
$20.00