Rapid Method to Obtain Carbonate-free Residues from Limestone and Petrocalcic Materials1
- M. C. Rabenhorst and
- L. P. Wilding2
A relatively rapid procedure for carbonate removal was desired for the study of noncarbonate residues from indurated calcareous materials. Carbonates were therefore removed from two calcareous smectite containing samples using various acid treatments. The degree of clay mineral alteration was assessed by x-ray diffraction (XRD) and cation exchange capacity (CEC) of residue clay (< 2-µm) fractions. Minor reductions in CEC were observed as a consequence of carbonate removal using pH 5.0 sodium acetate (NaOAc) buffer. Mineralogical changes were not detected by XRD. Further lowering of the NaOAc buffer pH to 2.5 had little or no additional effect. Use of pH 4.5 NaOAc buffer for dissolution of gravel size (< 8-mm) limestone and petrocalcic materials greatly reduced the time necessary for carbonate removal compared with traditional pH 5.0 NaOAc procedures.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © .