Analysis of the Solid Phase

In order to describe a rock, its chemical and mineral composition, the structure, and characteristic physical properties of its particles have to be studied. In the case of soils, the soil organic matter and its properties also have to be investigated. 

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For the purpose of this case study we will select Isopropyl alcohol as the crystallization solvent and assume that the NRTL-SAC solubility curve for Form A has been confirmed as reasonably accurate in the laboratory. If experimental solubility data is measured in IPA then it can be fitted to a more accurate (but non predictive) thermodynamic model such as NRTL or UNIQUAC at this point, taking care with analysis of the solid phase in equilibrium. As the activity coefficient model only relates to species in the liquid phase we can use the same model with each different set of AHm and Tm data to calculate the solubility of the other polymorphs of Cimetidine, as shown in Figure 21. True polymorphs only differ from each other in the solid phase and are otherwise chemically identical. 

Infrared and Raman spectroscopy allow direct spectral analysis of the solid phase, thus avoiding the tedious cleavage of compounds from the solid support. With diagnostic bands in starting materials or products, IR and Raman spectroscopy in general are efficient in monitoring each reaction step directly on the solid phase. 

The sediment cake that resulted from squeezing was retained in its butyrate tube, sealed with end caps, and placed in a freezer for later analysis of the solid phase. Ignition loss, percent CaCOs, acid-volatile sulfide, and total nonvolatile sulfur were measured on many samples. Metal analyses were also made (Part II). 

In contrast to pore-water data, analysis of the solid phase shows extensive and comparable production of sulfide fixed as FeS (acid-volatile sulfide) in all areas. Deep-water stations show extensive loss of solid-phase sulfide either prior to or after conversion of FeS to FeS2 (pyrite). All stations have comparable standing crops of organic matter and all stations are capable of supporting approximately the same rate of sulfate reduction in the upper 10 cm of sediment where most decomposition takes place. 

This was used fw the analysis of the solid phases and the diagrams for the solubility of the multi-component waters-salt system resulting from salt crystallization from the exhaust and raw iodine-bromine brines. 

Broadhurst MG (1962) An analysis of the solid phase behavior of the normal paraffins. J. Research, Natl. Bur. Stand., 66A 241... 

Separation and analysis of the solid phase shows it to be predominantly polymer from the viscosity index improver with traces of other additives present, such as Base Number and antioxidant. 

Catalytic tests were performed in a gas-phase continuous-flow reactor. The outlet flow of the reactor was either sampled for the analysis of the gaseous components, or condensed in a dry frozen trap, for the analysis of the solid and liquid products. Two liquid layers formed an organic layer containing the unconverted n-hexane, and an aqueous layer, some products dissolved preferentially in the organic layer, others in the aqueous one. Both layers were analyzed by gas chromatography. 

Based on the previous analysis of the different transport phenomena, which determine the overall mass transport rate, the structure of the solid phase matrix is of extreme importance. In the case of any chromatographic process, the different diffusion restrictions increase the time required for separation, since any increase of the flow rate of the mobile phase leads to an increase of the peak broadening [12]. Thus, the improvement of the existing chromatographic separation media (column packing of porous particles) and hence the speed of the separation should enable the following tasks ... 

Principle The underlying principle of head space gas chromatography is the analysis of the vapour phase in equilibrium with the solid or liquid phase. 

Another traditional method used for polymer support characterization is elemental analysis. Its use as an accurate quantitative technique for monitoring solid-phase reactions has also been demonstrated [146]. Microanalysis can be extremely valuable if a solid-phase reaction results in the loss or introduction of a heteroatom (usually N, S, P or halogen). In addition, this method can be used for determination of the loading level of a functional group (e. g. usually calculated directly from the observed microanalytical data). For example, in many cases, the displacement of chloride from Merrifield resin has been used as a guide to determine the yield of the solid-phase reaction. 

There are two independent determinations of the solid-phase enthalpy of formation of magnesocene. The first measurement of 66.9 3.3 kJmor results from analysis of the hydrolytic reaction of magnesocene with aqueous H2SO4 (equation 21). 

Using an analysis similar to that for the energy balance of the gas and after assuming constant physical properties of the solid phase,... 

In the analysis above, the void volume of the fixed bed (sVR) is considered to be fully filled with the fluid phase, i.e. the fluid holdup based on the total volume of the bed he t is equal to the bed voidage e. While this is expected in the case of a gas as fluid, it is not always true in the case of a liquid, especially in the case of downflow operation. In the case of incomplete filling of the bed with the fluid phase, the active bed volume is lower, and thus a portion of the solid phase is not in contact with the fluid, or in other words, is inactive in terms of reaction. 

Thermodynamic predictions of the solid-phase composition have been very successful for the growth by MOCVD of group III-V compound semiconductors (e.g., InAs Sb and GaAs SbJ even though the gas-phase reactions are far from equilibrium (88-91). The procedure is also useful for estimating solid-vapor distribution coefficients of group II-VI compound semiconductors (e.g., Cd Hg e and ZnSe SJ grown by MOCVD (92). In the analysis, the gas phase is considered to be an ideal mixture, that is... 

D. Mills, J.S. Mason, P. Marjanovic, An analysis of the dense phase pneumatic conveying of cement in vertical pipelines. Proceedings of the 9th Powder and Bulk Solids Conference, Chicago, USA, May 1984, pp. 125-147. 

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