Kaolinite diffraction

Characterization of Interlayer Water. X-ray diffraction studies of the 10A hydrate show no hkl reflections indicating a lack of regularity in the stacking of the kaolin layers. In addition to the 10A hydrate, two other less hydrated kaolinites were synthesized. Both have one molecule of water for each formula unit in contrast to the 10A hydrate which has two. These less hydrated clays consequently have smaller d(001) spacings of 8.4 and 8.6 A. The synthesis conditions for these two hydrates are described in (22.). By studying the interlayer water in the 8.4 and 8.6A hydrates, it was possible to formulate a model of the water in the more complicated 10A hydrate. 

This information is reported as the percentage that each of the clay mineral type contributes to total identifiable clay mineral content of the noncarbonate clay-sized fraction of the surface sediments. These percentages were determined by x-ray diffraction, which is luiable to identify noncrystalline solids. Using this technique, clay minerals were found to comprise about 60% of the mass of carbonate-free fine-grained fraction. Most of the noncrystalline soUds are probably mixed-layer clay minerals. Carbonate was removed to facilitate the x-ray diffraction characterization of the clay minerals. In some cases, roimd off errors cause the sum of the percentages of kaolinite, illite, montmorillonite, and chlorite to deviate slightly from 100%. 

Na -loess clay, where batch experiments were analyzed by X-ray diffraction and infrared and far-infrared measurements. The adsorption isotherm (Fig. 8.36) shows that loess clay is selective for cesium cations. The raw material contained a large amount of quartz, and the clay material was a mixture of kaolinite and an interstrati-fied iUite-smectite mineral as a result, equilibrium Cs" adsorption data are not consistent with a single site Langmuir model. Cesium adsorption on this particular soil clay occurs by cation exchange on sites with various cesium affinities. At low concentration, far-infrared spechoscopy shows the presence of very selective adsorption sites that correspond to internal collapsed layers. At high concentration, Cs MAS-NMR shows that cesium essentially is adsorbed to external sites that are not very selective. 

Feldspar, among many natural substances such as termite mount-clay, saw dust, kaolinite, and dolomite, offers significant removal ability for phosphate, sulfate, and color colloids. Optimization laboratory tests of parameters such as solution pH and flow rate, resulted in a maximum efficiency for removal of phosphate (42%), sulfate (52%), and color colloids (73%), x-ray diffraction, adsorption isotherms test, and recovery studies suggest that the removal process of anions occurs via ion exchange in conjunction with surface adsorption. Furthermore, reaction rate studies indicated that the removal of these pollutants by feldspar follows first-order kinetics. Percent removal efficiencies, even under optimized conditions, will be expected to be somewhat less for industrial effluents in actual operations due to the effects of interfering substances [58]. 

The problem with limited selectivity includes some of the minerals which are problems for XRD illite, muscovite, smectites and mixed-layer clays. Poor crystallinity creates problems with both XRD and FTIR. The IR spectrum of an amorphous material lacks sharp distinguishing features but retains spectral intensity in the regions typical of its composition. The X-ray diffraction pattern shows low intensity relative to well-defined crystalline structures. The major problem for IR is selectivity for XRD it is sensitivity. In an interlaboratory FTIR comparison (7), two laboratories gave similar results for kaolinite, calcite, and illite, but substantially different results for montmorillonite and quartz. 

This eliminated enough of the carbon to get readable patterns. The major minerals determined were quartz, calcite, kaolinite, and chlorite. The most obvious and abundant mineral, quartz, decreased in relative amounts toward the center of the xenolith, and this trend was apparent in all the other minerals. Diffraction patterns of the ash from the whole coke, in general, showed the same mineral decrease trend except, of course, no calcite at all was detectable. Calcination or emission of carbon dioxide from calcite occurs at 898°C. (7), significantly below the ashing temperature of 950°C. 

In order to substantiate further the mineral matter content information received from the x-ray diffraction analyses, several coke pellets were scanned for sulfur, iron, calcium, silicon, aluminum and potassium in the electron microprobe. Electron probe results showed abundant silicon, suggesting quartz (Si02), considerable aluminum, suggesting kaolinite [Ali>Sii Oii(OH)4] and, relatively speaking, little iron, sulfur, calcium, or potassium. 

The proportion of ipso nitration product first depends upon the amount of clay present in the reaction mixture, then reaches a plate. This limit can square wi(- a clay saturation. The results obtained by X-ray diffraction studies on the kaolinite separated from t h e... 

At a temperature near 150°C kaolinite starts to decompose and the Al as hy-droxy-Al moves into the interlayer position increasing the proportion of dioctahedral chlorite layers. At this stage some of the chlorite layers form packets with a sufficient number of layers to diffract as the discrete mineral chlorite. Some additional Al may move into the tetrahedral sheet at this stage and some packets of 10A layers form (the K derived from K-feldspar). Thus, the amount of discrete 10A illite and dioctahedral chlorite has increased slightly but the majority of the clay consists of a mixed-layer illite-chlorite with a lesser amount of montmorillonite. 

Mineralogy. The most important mineral constituents were determined by X-ray diffraction for five samples (four of them from NR-10). Quartz and opal (mainly CT) are important components in all five samples. In a marl (NR-10, 81.5 m), calcite, kaolinite, pyrite, gypsum and illite/smectite mixed-layer minerals occur in addition to those. 

Figure 9. Controlled-environment X-ray diffraction patterns of a kaolinite-hydrazine intercalate in the 7 to 11 ° 20 region, obtained as a function of pressure at 298 K.

Many experimental investigations of intercalates dickite-FA (D-FA), dickite-MFA (D-MFA) and kaolinite-DMSO (K-DMSO) applied IR and Raman spectroscopy, NMR technique and X-ray diffraction. These works are mostly devoted to the study of the position of the organic molecule in the interlayer space of kaolinite, interactions between the organic molecule and the layers of dickite and kaolinite, and the influence of mineral structure to the intercalation capability. 

In our studies, the model substance (montmorillonite) was a calcium bentonite (Istenmezeje, Hungary), the characteristic features of which are given here. X-ray diffraction (intensity of the basal reflection) and thermoanalytical (weight loss upon heating) data show 91% montmorillonite content. The other constituents are 5% calcite, 3% kaolinite, 1% x-ray amorphous silicates, and a trace of quartz. The amorphous phase is silicate particles, which are not crystalline for... 

Obviously, the dissolution of the elements leads to change in the crystal lattice and the mineral composition. This can well be seen during the acidic treatment of montmorillonite or bentonite for catalytic purposes (Section 2.1). The treatment is done using concentrated hydrochloric, sulfuric, or phosphoric acid. X-ray diffraction studies show that a commercially available montmorillonite has low montmorillonite content (53%). The other constituents are illite 10%, kaolinite 6%, quartz 10%, plagioclase 5%, gypsum 1%, anhydrite 4%, and amorphous 7%. 

This study is concerned with four different mixtures, including kaolinite and calcite (kc) kaolinite and dolomite (kd) montmorillonite and calcite (me) and montmorillonite and dolomite (md). All the mixtures, by weight, were 95% clay and 5% carbonate mineral. The minerals were first ground to a fine powder and thoroughly mixed by hand before heating in a muffle furnace (temperature controlled to within 20 °C). Each mixture was heated for 1 h, air quenched at room temperature, and analyzed by X-ray diffraction. X-ray films were made in cameras of 11.46-cm diameter with filtered copper radiation and exposure times of 6 h. Several wet mixtures that simulated ceramic paste before firing were heated and studied in like manner, but they showed no differences from the dry mixtures. 

The amount of adsorbed metal was determined by the weight difference of the pre-and post-sorption sorbent. The structural and morphological change of kaolinite granules during sorption tests was investigated by the powdered X-ray diffraction (XRD) analysis (Philips, X pert MPD) and scanning electron microscopy (SEM) (JEOL, JXA 8600). 

The differences in iron and trace element concentrations are a result of differences in the source of the material (which minerals are present) and the depositional differences (heavy mineral fraction present). When the sediments were analyzed by x-ray diffraction techniques, the only minerals observable, besides the clays (montmorillonite and kaolinite), were the quartz and plagioclase (2J). Most of the iron appears to be... 

In addition to those minerals associated with the granular constituent, there are numerous submicron-sized minerals that are intimately mixed with other coal macerals. A typical example can be seen in Figure 11, which is a TEM micrograph of vitrinite, where the circular aperture identifies the region from which the electron diffraction pattern, shown in the inset, was obtained. The mineral, which was identified as kaolinite, appears to have been deposited as plates parallel with the coal bedding, based upon an analysis of the diffraction pattern. Also present in these coals is the clay mineral illite, which can be distinguished from kaolinite by both EDX and SAD analyses, lllites contain potassium (K)... 

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