Solid-phase carbonization

The study of carbon electrodeposition from carbonate and halide- carbonate melts was devoted a cycle of works [1 - 6]. It was found that under certain conditions carbon solid phase was formed on cathode with 100 % current yield. The questions of product morphology, structure and dispersity had remained not opened because of absence at that time analysis technical equipment with high-resolution. Different schools of the electrochemists offered various mechanisms of carbon phase formation ... 

The aim of the present work is the fulfillment of the complex studying (a) -investigation of peculiarities of carbon solid phase electrodeposition from halide melts, saturated by carbon dioxide under excessive pressure up to 1.5 MPa in temperatures range 500 - 800 °C (b) - elucidation of electrode processes mechanism (c) - characterization of produced carbon powders (d) - establishment of correlation between product structure and yield against electrolysis conditions and regimes. 

Shoemaker, J. A., Novel chromatographic separation and carbon solid-phase extraction of acetanihde herbicide degradation products, J. AOAC Int, 85, 1331-1337, 2002. 

The following thorium carbonate solid phases have been synthesised in corresponding bicarbonate or carbonate solutions and characterised by chemical analysis, thermogravimetry and X-ray diffraction ... 

This study was in real time measured that the reflective echo height of the bonding interface in the solid phase diffused bonding process of carbon steel and titanium using ultrasonic testing method. As a result, the following were made discernment. 

It is noted in Sections XVII-10 and 11 that phase transformations may occur, especially in the case of simple gases on uniform surfaces. Such transformations show up in q plots, as illustrated in Fig. XVU-22 for Kr adsorbed on a graphitized carbon black. The two plots are obtained from data just below and just above the limit of stability of a solid phase that is in registry with the graphite lattice [131]. 

Fig. XVII-22. Isosteric heats of adsorption for Kr on graphitized carbon black. Solid line calculated from isotherms at 110.14, 114.14, and 117.14 K dashed line calculated from isotherms at 122.02, 125.05, and 129.00 K. Point A reflects the transition from a fluid to an in-registry solid phase points B and C relate to the transition from the in-registry to and out-of-registry solid phase. The normal monolayer point is about 124 mol/g. [Reprinted with permission from T. P. Vo and T. Fort, Jr., J. Phys. Chem., 91, 6638 (1987) (Ref. 131). Copyright 1987, American Chemical Society.]...

In gas-solid extractions the sample is passed through a container packed with a solid adsorbent. One example of the application of gas-solid extraction is in the analysis of organic compounds for carbon and hydrogen. The sample is combusted in a flowing stream of O2, and the gaseous combustion products are passed through a series of solid-phase adsorbents that remove the CO2 and 1T20. 

H2/Pd-C, EtOH, 20°. < -Bromobenzyl carbonates have been developed for use in solid-phase peptide synthesis. An aryl o-bromobenzyl carbonate is stable to acidic cleavage (CF3CO2H) of a /-butyl carbamate a benzyl carbonate is cleaved. 

The iron-carbon solid alloy which results from the solidification of non blastfurnace metal is saturated with carbon at the metal-slag temperature of about 2000 K, which is subsequendy refined by the oxidation of carbon to produce steel containing less than 1 wt% carbon, die level depending on the application. The first solid phases to separate from liquid steel at the eutectic temperature, 1408 K, are the (f.c.c) y-phase Austenite together with cementite, Fe3C, which has an orthorhombic sttiicture, and not die dieniiodynamically stable carbon phase which is to be expected from die equilibrium diagram. Cementite is thermodynamically unstable with respect to decomposition to h on and carbon from room temperature up to 1130 K... 

J. Slobodnik, O. Ostezkizan, H. Lingeman and U. A. Th Brinkman, Solid-phase extraction of polar pesticides from environmental water samples on grapliitised carbon and Empore-activated carbon disks and on-line coupling to octadecyl-bonded silica analytical columns , J. Chromatogr. 750 227-238 (1996). 

Of this material 1.0 g is dissolved in 150 ml of warm 95% ethyl alcohol. To the solution is added 1.0 g of 5% palladium on carbon catalyst, and the mixture is hydrogenated at room temperature and atmospheric pressure by bubbling hydrogen into it for 3 hours with stirring. The hydrogenation product is filtered. The solid phase, comprising the catalyst and the desired product, is suspended in ethyl acetate and water and adjusted to pH 2 with hydrochloric acid. The suspension is filtered to remove the catalyst. The aqueous phase is separated from the filtrate, and is evaporated under vacuum to recover the desired product, 7-(D-a-aminophenylacetamido)cephalosporanic acid. 

It is well to add that most of the compounds of carbon condense to molecular liquids and solids. Their melting points are generally low (below about 300°C) and many carbon compounds boil below 100°C. The similar chemistry of the liquid and solid phases shows the retention of the molecular identities. 

Massimilla et al. (M5) measured the rate of absorption of carbon dioxide in water from a mixture of carbon dioxide and nitrogen. Used as solid phase were silica sand particles of average equivalent diameter 0.22 mm, or glass ballotini of average equivalent diameter 0.50 and 0.80 mm. Columns of 30-and 90-mm i.d. were used, and the column height was varied from 100 to 1200 mm. 

Intermolecular forces are responsible for the existence of several different phases of matter. A phase is a form of matter that is uniform throughout in both chemical composition and physical state. The phases of matter include the three common physical states, solid, liquid, and gas (or vapor), introduced in Section A. Many substances have more than one solid phase, with different arrangements of their atoms or molecules. For instance, carbon has several solid phases one is the hard, brilliantly transparent diamond we value and treasure and another is the soft, slippery, black graphite we use in common pencil lead. A condensed phase means simply a solid or liquid phase. The temperature at which a gas condenses to a liquid or a solid depends on the strength of the attractive forces between its molecules. 

Silicon is the second most abundant element in the Earth s crust. It occurs widely in rocks as silicates, compounds containing the silicate ion, Si032, and as the silica, Si02, of sand (Fig. 14.33). Pure silicon is obtained from quartzite, a granular form of quartz (another solid phase of SiOz), bv reduction with high-purity carbon in an electric arc furnace ... 

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