Asbestos extraction

Cd3[Fe(CN)6]2 and asbestos. Extract with NaOH solution, acidify extract wit dilute HCI, add freshly prepared FeS04 solution. Precipitate of Prussian blue indicates hexacyanoferrate(III). 

Sodium bismuthate (oxidation of manganese) heat 20 parts of NaOH nearly to redness in an iron or nickel crucible, and add slowly 10 parts of basic bismuth nitrate which has been previously dried. Add 2 parts of sodium peroxide, and pour the brownish-yellow fused mass on an iron plate to cool. When cold break up in a mortar, extract with water, and collect on an asbestos filter. 

Ores which comprise a variety of minerals are, as a rule, heterogeneous. An ore body is usually named for the most important mineral (s) in the rock, referred to as value minerals, mineral values, or simply values. Some minerals contain metals, which are extracted by concentration and smelting. Other minerals, such as diamond, asbestos (qv), quartz (see Silicon COMPOUNDS), feldspars, micas (see Mica), gypsum, soda, mirabillite, clays (qv), etc, maybe used either as found, with some or no pretreatment, or as stock materials for industrial compounds or building materials (qv) (3). 

The fiber extraction (milling) process must be chosen so as to optimize recovery of the fibers in the ore, while minimizing reduction of fiber length. Since the asbestos fibers have a chemical composition similar to that of the host rock, the separation processes must rely on differences in the physical properties between the fibers and the host rock rather than on differences in their chemical properties (33). 

Phenylcyclopropene (5). 3 (118 g 0 8 mol), powdered KOH (30 g, 0 S3 mol) and platinize asbestos (2 5 g) were heated slowly and the heat was shut off at the rirsi sign of reaction Afler the exolhemiic reaction the temperature was again raised and the product was distilled Both the distillate end the residue were steam distiled, the distitlate was extracted with Et20... 

It is satisfactory to use the Super-Cel brand of kieselguhr supplied by Johns-Manville Company and asbestos of the type used in Gooch crucibles. Inclusion of these inert materials facilitates mixing and extraction of the product. 

At this point 20-30 g. of short glass fiber or asbestos is added and the yeast is filtered out by suction. The filtrate is concentrated to a thick syrup under diminished pressure on a water bath, care being taken to keep the temperature below 40° (Note 3). The residue (about 200 cc.) is taken up in a mixture of 400 cc. of absolute alcohol and 100 cc. of dry ether (Note 4). The precipitate formed is removed by centrifuging, the supernatant liquid is decanted, and the residue is extracted with a mixture of 200 cc. of 98.5 per cent alcohol and 100 cc. of dry... 

Another problem is the extent of regulative measures. On the one hand, the use of asbestos is now almost completely banned in the European Union and in many other industrialised and economically thriving countries. On the other hand, more than 2 milhon tons of asbestos are extracted and consumed globally every year. A uniform global hazardous substances pohcy evidently does not exist yet. 

In an electrolytic cell (Fig. 5) consisting of platinum electrodes (2 cm x 5 cm in area) and cathode and anode compartments separated by an asbestos divider, each compartment is charged with 17 g (0.4 mol) of lithium chloride and 450 ml of anhydrous methylamine. Isopropylbenzene (12 g, 0.1 mol) is placed in the cathode compartment and a total of 50,000 coulombs (2.0 A, 90 V) is passed through the solution in 7 hours. After evaporation of the solvent the mixture is hydrolyzed by the slow addition of water and extracted with ether the ether extracts are dried and evaporated to give 9.0 g (75%) of product boiling at 149-153° and consisting of 89% of a mixture of isomeric isopropylcyclohexenes and 11% of recovered isopropylbenzene. 

Warm cautiously on a steam bath over a thin sheet of asbestos for 15 mins, breaking up any lumps by very cautious use of a rubber policeman attached to a glass rod. Cool to RT, let settle and decant the ale shellac soln through a small tared, previously ignited and cooled, 30 ml Gooch or Selas crucible. Repeat the extraction with new portions of abs ale until the shellac is completely removed(about 3 times). Transfer... 

ASBESTOS. The tenn asbestos is a generic designation referring usually to six types of naturally occurring mineral fibers which are or have been commercially exploited, These fibers are extracted from certain varieties of hydrated alkaline silicate minerals comprising two families seipe.ntin.es and amphiboles. The serpentine group contains a single fibrous variety chrysotile five fibrous forms of amphiboles are known anthophyllite, amosite, crocidolite. tremolite, and actinolite... 

In either case the dish with the extract is placed on an asbestos sheet and the drying of the extract commenced over a small flame, care being taken to avoid loss. The dish is subsequently heated directly over a flame, the extract being charred, the mass extracted with water, the aqueous extract filtered through a small ashless filter, all the carbon burnt away, and the aqueous extract and filter added to the same dish. 

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