Bomb furnace

Carius furnace, tube furnace, bomb furnace, bomb oven SchieBrohr/... 

The reactor used for the aluminothermic reduction of niobium pentoxide is shown schematically in Figure 4.17 (A). It is a steel pipe, lined on the inside with alumina and provided with a pipe cap. The charge, consisting of stoichiometric amounts of niobium pentoxide and aluminum powder, is blended and loaded in the lined pipe, and covered with alumina. The cap is closed and the reaction initiated by placing the loaded bomb in a gas-fired furnace, preheated to 800 °C, and by raising the temperature of the furnace to 1100 °C. 

In the Antek Fluoride Analyzer, a pyrolysis furnace is combined with an ion-specific electrode cell (ISE). Table 8.9 compares this specific analyser to a conventional combustion bomb. 

Heating the Tube.—Place the iron case with its tube in a bomb or tube furnace in such a way that the end with the capillary is raised somewhat and directed towards the wall on which a shield is fixed and close the furnace. Several tubes may be heated simultaneously. Light all the burners and heat gradually to the desired temperature, regulating the gas supply at the main tap. For aliphatic halogen compounds (and many sulphur compounds) this temperature is about 250°, for the aromatic compounds (and sul-phonic acids) it is about 300°. Most substances are completely oxidised after three to four hours, but in the case of aromatic compounds the heating is continued for some hours longer. 

The bomb method for sulfur determination (ASTM D129) uses sample combustion in oxygen and conversion of the sulfur to barium sulfate, which is determined by mass. This method is suitable for samples containing 0.1 to 5.0% w/w sulfur and can be used for most low-volatility petroleum products. Elements that produce residues insoluble in hydrochloric acid interfere with this method this includes aluminum, calcium, iron, lead, and silicon, plus minerals such as asbestos, mica, and silica, and an alternative method (ASTM D1552) is preferred. This method describes three procedures the sample is first pyrolyzed in either an induction furnace or a resistance furnace the sulfur is then converted to sulfur dioxide, and the sulfur dioxide is either titrated with potassium iodate-starch reagent or is analyzed by infrared spectroscopy. This method is generally suitable for samples containing from 0.06 to 8.0% w/w sulfur that distill at temperatures above 177°C (351°F). 

The Determination of Selenium. The most difficult trace element to determine in coal by wet chemical methods is selenium. Two alternative dissolution techniques can be used—H. L. Rooks combustion method (7) and the oxygen bomb combustion method (4). Also, two alternative analytical methods can be used—the hydride evolution method (5) and the graphite furnace method. 

The graphite furnace method can also be used as described in the bomb combustion procedure. Table V compares graphite furnace values with conventional flame AAS or NBS neutron activation analyses. 

Iron Monarsenide, FeAs, may be obtained by heating iron in a current of arsenic vapour at 335° to 380° C. 2 by heating a mixture of the elements in a bomb tube at 680° C.,3 or a mixture of iron, arsenious oxide and carbon in an electric arc furnace 4 by the action of fused potassium cyanide on iron arsenate 8 by reduction of the di-arsenide at 680° C. in a current of hydrogen 3 or by dropping a solution of a ferrous salt into an atmosphere of arsine.6... 

Tube Furnace or Bomb Furnace.—When cold, the tube is transferred to the removable metallic cylinder of the tube furnace (Fig. 40). The cap of the cylinder is screwed on and the latter placed in position in... 

Method I.—5 gms. pure p-nitrotoluene, 2 c.cs. of bromine, and a crystal of iodine are placed in a sealed tube. The tube is placed in a bomb furnace and gradually heated up during 40 minutes to 130°, at which temperature it is maintained for 160 minutes. After cooling, the tube is opened and the product extracted with about 60 c.cs. of hot alcohol. From the resulting solution crystals separate on cooling, which are filtered off a second crop is obtained after concentrating and cooling the mother liquor. Water is added to the final mother liquor to precipitate a small quantity of the nitrobenzyl bromide, which is filtered off, dried, and purified by recrystallisation from petroleum ether. The first and second crops should be washed with cold petroleum ether. 

B. 2,6,6-Trimethyl-2,4-cyclohexadienone. In a nitrogen-filled dry box, 25.0 g. of lithium 2,6-dimethylphenoxide (0.195 mole) is transferred to an oven-dried, thick-walled Pyrex bomb tube (650 x 19 mm.). The bomb tube is stoppered with a rubber stopper fitted with a drying tube, removed from the dry box, and 75 ml. of methyl iodide (170 g., 1.20 moles) (freshly distilled from calcium hydride) is quickly pipetted into the bomb under a dry nitrogen stream. The bomb is cooled in a dry-ice bath and sealed with an oxygen torch. After warming to room temperature, the bomb is shaken to disperse the salt cake and placed in a bomb furnace which has been preheated to 135° (Note 7). 

After 36 hours the furnace is allowed to cool, the bomb is removed, cooled to dry-ice temperatures, and opened carefully as there may be residual pressure. The golden brown liquid is poured into a 200-ml. flask, and the methyl iodide is removed on a rotary evaporator (iCautionI Hood). The residue from the flask and the bomb is washed into a 500-ml. separatory funnel with 100 ml. each of ether and 1 1 solution of Claisen s alkali and water (Note 8). The funnel is shaken, and the alkali layer is removed. The ether layer is extracted four additional times with 100 ml. portions of the alkali (Note 9), washed twice with 75-ml. portions of water, once with saturated aqueous salt solution, and... 

Those who have imagined that it was formed in the air principle of hard bodies such as aerolites, have been mistaken, if they have regarded them as terrestrial bodies. It is a substance which belongs to the gross element of Water a fat, viscous humour, enclosed in the clouds as in a furnace, where it condensed and mixed with the sulphurous exhalations, which are warm and very inflammable. The air, which is too much compressed by this condensation, is rarefied by heat, and produces the same effect as gunpowder in a bomb the vessel breaks, the fire diffused in the air, freed from its bonds by this movement, produces that light and noise, which often startle the most intrepid. 

Spotting charges for practice bombs and mines Artillery shell training adaptors Cleaning industrial furnaces... 

Cold-seal stellite bombs and high oxygen pressures were used as described previously (6, 7, 8, 9, 10). An ordinary pot furnace was used for heat treatments carried out in air. As starting materials, purified palladium black (Fisher Scientific Co.) was mixed intimately with the other oxides or hydroxides [PbO, Sr(OH)2 8H20, CaO, CdO, Mg(OH)2]. The mixtures generally were inserted into gold foils and heat treated under various conditions of temperature and oxygen pressure. The runs were quenched and the products examined by x-ray diffraction. 

The procedure for preparing the crystals of the CA-M adduct was as follows. Aqueous solutions of cyanuric acid (0.1 mmol) and melamine, (0.1 mmol) were mixed in a Teflon flask, and the mixture (15 mL) was kept in a stainless steel bomb. The bomb was sealed and maintained in a furnace at 180 °C. Rectangular platelike crystals of good quality separated from the solution, upon cooling the bomb to room temperature over a period of 4 h. These crystals were used for collecting intensity data on the single-crystal... 

The char precursors were carbonized at 823 K for 90 minutes under a nitrogen pressure of 0.68 MPa in tubing bomb reactors. The carbonaceous residues were subsequently heat treated at 1273 K for 1 hour under argon in a tube furnace to drive off residual volatile matter. The carbonization was conducted to increase char yield direct heat treatment of the precursors would result in very low char yeilds. The high heat treatment temperature was chosen to ensure that at the lower temperature used in the oxidation experiments, there would be no volatile material, thus ensuring that the reaction was heterogeneous. 

Cooking range 15 Factory furnace 4 Propane bomb 1... 

Furthermore, it is useful to limit the salt content of the solution. This generally means that the furnace technique should only be used to determine trace elements soluble in acids — possible after pressure bomb decomposition. In this case the time of analysis becomes irrelevant. An example is the determination of Cd-traces in iron ores and related oxides. 

The Pb-Na alloys with high Na content (71-89 at % Na = 21-47 wt% Na) are made on a laboratory scale in a steel bomb in an electric furnace at 420°C by fusing the components , and Pb-Na alloys with lower Na content are prepared by adding Na metal lumps to molten Pb at the lowest possible T using a steel crucible . Fireclay crucibles are also used . 

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