| |
Rezumat articol ediţie STUDIA UNIVERSITATIS BABEŞ-BOLYAI
În partea de jos este prezentat rezumatul articolului selectat. Pentru revenire la cuprinsul ediţiei din care face parte acest articol, se accesează linkul din titlu. Pentru vizualizarea tuturor articolelor din arhivă la care este autor/coautor unul din autorii de mai jos, se accesează linkul din numele autorului. |
|
| |
Rezumat: Three different kaolin types used in the ceramic industry (KO1 and MK2 kaoline from Ucraina and respectively BOJ kaoline from Bulgaria) were analysed by different methods in order to obtain a complete mineralogical and technological characterisation. Studies were carried out by using a combination of analyses of both, the bulk sample and the fine fraction. Following a well-established pre-treatment methodology (use of chemical reactives, ultrasonic treatment, dispersion procedures), clay mineral concentration by centrifugation and sedimentation, oriented and random powder preparation, cation saturation, expansion/dehydration methods, a number of 12 X-ray diffraction (XRD) patterns were obtained for each sample. The interpretation of XRD patterns of the bulk samples, and of the fine clay fraction (< 2 m) led to the identification of the following mineral phases: kaolinite, illite, quartz, and in a single one sample, also vermiculite. The semiquantitative mineralogical composition was determined based on peak intensities (mostly of lower orders) and peak areas corrected by various factors. The Hinckley crystallinity index was obtained measuring the heights of the (1 0) and (11 ) peaks. Scanning electron microscopy was also used in order to illustrate the identified mineral phases. For a better characterisation, the cation exchange capacity (CEC) and surface area (SA) were also measured by absorption of methylene blue. The particle size distribution was obtained using a laser granulometer. ... |
|
