Iron chloride graphite

Typical X-ray diffraction patterns of three different carbon powder samples are shown in Fig. 3. Two 00/ and two hkO diffraction peaks can be distinguished in the patterns of samples produced at 800°C and 1000°C. The 002 (26 26.9°) and 004 (26 54.9°) peaks correspond to the parallel graphene layers. The 100 (26 43°) and 110 (26 77.8°) diffraction peaks are characteristics of the 2D in-plane symmetry along the graphene layers. Based on its XRD pattern, the powder synthesized at 500°C is not graphitized, which is in agreement with Raman analysis. This low temperature sample also contains traces of iron chlorides. 

Chlorination of Fe3C at temperatures of 400°C and above results in the formation of carbon and solid or gaseous iron chlorides. Three temperature regimes have been defined. Amorphous carbon is formed at temperatures of 400 500°C. Flakes and ribbons of nanocrystalline graphite form at 600 -... 

The experimental protocol for this research involves several essential features. First, no redox transformations are allowed. Ferrous and ferric iron chlorides are introduced into strictly anaerobic aqueous systems, with careful exclusion of oxygen (Q. Second, pH and the potentials at platinum and wax-impregnated graphite (WIG) electrodes are recorded as a function of time, beginning shortly after the addition of ferric chloride. 

Fused Salt Electrolysis. Only light RE metals (La to Nd) can be produced by molten salt electrolysis because these have a relatively low melting point compared to those of medium and heavy RE metals. Deposition of an alloy with another metal, Zn for example, is an alternative. The feed is a mixture of anhydrous RE chlorides and fluorides. The materials from which the electrolysis cell is constmcted are of great importance because of the high reactivity of the rare-earth metals. Molybdenum, tungsten, tantalum, or alternatively iron with ceramic or graphite linings are used as cmcible materials. Carbon is frequently used as an anode material. 

Graphite 2 -5-10 A/m Consumption rate very much less than steel or cast iron (< 1 kg/Ay) chloride ions reduce consumption... 

Heal content, 110. 116 change (luring a reaction, 110 of a substance, 109 Heat of combustion of diamond, 122 graphite, 122 hydrazine, 47 hydrogen, 40 methane, 123 Heat of formation, 113 Heat of reaction, 135 between elements, table, 112 oxidation of HC1, 160 oxidation of sulfur dioxide, 161 predicting, 112 Heat of reaction to form ammonia, 112 Br atoms, 290 carbon dioxide, 112 carbon monoxide, 112 Cl atoms, 290 CO + Hi, 110 ethane, 112 F atoms, 290 H atoms, 274 hydrogen chloride, 160 hydrogen iodide, 112 iron(Ill) oxide, 162 Li atoms, 290 Li + Br, 290 Li + F, 290 Na + Cl, 290 NHs products, 114 Na atoms, 290 NO, 112 NOj, 112... 

The electrolyte is made by in situ chlorination of vanadium to vanadium dichloride in a molten salt bath. Higher valent chlorides are difficult to retain in the bath and thus are not preferred. The molten bath, which is formed by sodium chloride or an equimolar mixture of potassium chloride-sodium chloride or of potassium chloride-lithium chloride or of sodium chloride-calcium chloride, is contained in a graphite crucible. The crucible also serves as an anode. Electrolysis is conducted at a temperature about 50 °C above the melting point of the salt bath, using an iron or a molybdenum cathode and a cathode current density of 25 to 75 A dnT2. The overall electrochemical deposition reaction involves the formation and the discharge of the divalent ionic species, V2+ ... 

The catalytic effect of graphite A thus depends on iron impurities, e. g. Fe304, and probably also on iron sulfides or sulfates, because sulfur is also present in this graphite, and all these iron compounds are known catalysts of FC acylation [69, 73, 74], In this respect, it seems that FeCl3 could be the true catalyst generated in situ by the reaction of the different iron compounds with acid chloride and hydrogen chloride. In the... 

A graphite furnace procedure has been described [674] for the direct determination of iron, chromium, and manganese in seawater and estuarine waters in which the interference normally associated with the presence of sodium chloride is eliminated. The technique requires only very small sample volumes (10-20 il) for the atomisation stage. The reproducility of the method was very good. Sensitivities of 0.4,0.2, and 0.07 xg/l and precisions of determination of 4.5,3, and 11% (at 2 xg/l level) were obtained for iron, manganese, and zinc. 

Montgomery and Peterson [675] showed that ammonium nitrate used as a matrix modifier in seawater analysis to eliminate the interference of sodium chloride degrades the pyrolytic coating on graphite-furnace tubes. The initially enhanced sensitivities for copper, manganese, and iron are maintained for up to 15 atomisations. There is then a rapid decline to a constant lower sensitivity. The characteristics depend strongly on the particular lot of furnace tubes. To... 

In the electrolytic process, a fused mixture of anhydrous rare earth chlorides (obtained above) and sodium or potassium chloride is electrolyzed in an electrolytic cell at 800 to 900°C using graphite rods as the anode. The cell is constructed of iron, carbon or refractory hnings. Molten metal settles to the bottom and is removed periodically. 

There are two electrolytic methods that are of major importance. One involves the electrolysis of fused sodium chloride using the Downs cell. This method currently is most prevalent. The Downs cell consists of a steel cell with brick lining containing the fused bath. The multiple electrode arrangement consists of four cylindrical graphite anodes that project upward from the hase of the cell. Each anode is surrounded hy a diaphragm of iron gauge and a steel cathode. 

MetaUic strontium is produced by electrolysis of a mixed melt of strontium chloride and potassium chloride in a graphite crucible using an iron rod as cathode. The upper cathodic space is cooled and the strontium metal coUects over the cooled cathode and forms a stick. 

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