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Sulphur mineralization

Those minerals which are not from mercury, and those salts which are soluble in water, as alums, chalcanthum (sulphates of iron and copper), common salt, sal petrae, and some substances insoluble in water alone, as orpiment, arsenicum, sulphur and other sulphurous minerals, result from the aqueosity of sulphurs mixed with viscous earths firmly united by a fervent heat, whence they are rendered unctuous and afterward solidified by cold. The medieval chemical philosophers generally do not devote so much attention to the fundamental composition of nonmetallic minerals, and the classification here given by Richardus as to their origin is by no means in accord with others, especi-... [Pg.213]

Extraction.—(1) From Pyrites.—In the oxidation of the pyrites (or other sulphur mineral) for the formation of sulphur dioxide in the manufacture of sulphuric acid, foreign elements like arsenic and selenium also undergo oxidation and pass ofC as vapours with the sulphur dioxide. The selenium dioxide produced in this manner their suffers more or less complete reduction by the sulphur dioxide, when finely divided selenium separates, mainly in the lead chambers, as a red, amorphous powder, accompanied possibly by some of the greyish-black form a portion of the dioxide is also found in the Glover tower acid. The amount of selenium in the chamber mud depends, of course, on the nature of the pyrites relatively large quantities of compounds of arsenic, zinc, tin, lead, iron, copper or mercury are always present, arising almost entirely from impurities in the pyrites. [Pg.287]

Edwards K. J., Bond P. L., and Banfield J. E. (2000a) Characteristics of attachment and growth of Thiobacillus caldus on sulphide minerals a chemotactic response to sulphur minerals Environ. Microbiol. 2, 324—332. [Pg.4264]

A new method based on thermomechanical analysis of solid (not dissolved) polymer was used to study the topology and molecular structure of different kinds of sulphur (mineral and two polymeric types), commonly used as vulcanising agents for diene rubbers. It was found that a significant difference existed in their MWDs and in their degrees of crystallinity. Both mineral and polymeric sulphurs had a polymeric nature. 9 refs. EASTERN EUROPE POLAND RUSSIA Accession no. 645667... [Pg.106]

On acetylation it gives acetanilide. Nitrated with some decomposition to a mixture of 2-and 4-nitroanilines. It is basic and gives water-soluble salts with mineral acids. Heating aniline sulphate at 190 C gives sulphanilic add. When heated with alkyl chlorides or aliphatic alcohols mono- and di-alkyl derivatives are obtained, e.g. dimethylaniline. Treatment with trichloroethylene gives phenylglycine. With glycerol and sulphuric acid (Skraup s reaction) quinoline is obtained, while quinaldine can be prepared by the reaction between aniline, paraldehyde and hydrochloric acid. [Pg.35]

If only the monocarboxybc acid is required, the ester after hydrolysis with potash may be strongly acidified with sulphuric acid and the mixture heated under reflux the mineral acid promotes decarboxylation at a temperature just above 100°. The net result is the replacement of the halogen atom of the alkyl halide by —CH COOH thus in the above example ... [Pg.484]

Mix 1 g. of the nitro compound with 4 g, of sodium dichromate and 10 ml. of water in a 50 ml. flask, then attach a reflux condenser to the flask. Add slowly and with shaking 7 ml. of concentrated sulphuric acid. The reaction usually starts at once if it does not, heat the flask gently to initiate the reaction. When the heat of reaction subsides, boil the mixture, cautiously at first, under reflux for 20-30 minutes. Allow to cool, dilute with 30 ml. of water, and filter oflF the precipitated acid. Purify the crude acid by extraction with sodium carbonate solution, precipitation with dUute mineral acid, and recrystaUisation from hot water, benzene, etc. [Pg.529]

NITRATION IN AQUEOUS SOLUTIONS OF MINERAL ACIDS 2.4.1 The state of nitric acid in aqueous sulphuric acid Nitric acid is completely converted into nitronium ions in concentrated sulphuric acid ( 2.3.1) ... [Pg.19]

NaiCOfl or ctileitim hydroxide (Ca(OH)2). i.e. lime water. The basic (alkaline) effluents can be treated with any mineral acid, preferably sulphuric acid (Hi.SOj). until the required pH value is obtained. [Pg.417]

Impurities in mineral fillers can have serious effects. Coarse particles (grit) will lead to points of weakness in soft polymers which will therefore fail under stresses below that which might be expected. Traces of copper, manganese and iron can affect the oxidative stability whilst lead may react with sulphur-containing additives or sulphurous fumes in the atmosphere to give a discoloured product. [Pg.127]

The principal applications of these plastics arose from their very good chemical resistance, as they are resistant to mineral acids, strong alkalis and most common solvents. They were, however, not recommended for use in conjunction with oxidising acids such as fuming nitric acid, fuming sulphuric acid or chlorosulphonic acid, with fluorine or with some chlorinated solvents, particularly at elevated temperatures. [Pg.550]

Neutralization of strong mineral acids from metal finishing trades (sulphide and hypochlorite contamination common) Fierce reaction Possibility of mixing with water or organic materials Chlorine Nitrogen dioxide Sulphur dioxide Hydrogen sulphide... [Pg.500]

Mineral acid Hydrobromic acid Hydrochloric acid Hydrofluoric acid Nitric acid Sulphuric acid... [Pg.506]

Detection T. thio-oxidans is best detected by the strongly acid conditions it generates in a mineral salt solution on which sulphur is floating. [Pg.392]


See other pages where Sulphur mineralization is mentioned: [Pg.33]    [Pg.365]    [Pg.110]    [Pg.8]    [Pg.255]    [Pg.675]    [Pg.190]    [Pg.492]    [Pg.33]    [Pg.365]    [Pg.110]    [Pg.8]    [Pg.255]    [Pg.675]    [Pg.190]    [Pg.492]    [Pg.24]    [Pg.34]    [Pg.111]    [Pg.135]    [Pg.143]    [Pg.175]    [Pg.239]    [Pg.341]    [Pg.377]    [Pg.2777]    [Pg.376]    [Pg.122]    [Pg.379]    [Pg.765]    [Pg.1092]    [Pg.1]    [Pg.48]    [Pg.210]    [Pg.275]    [Pg.339]    [Pg.303]    [Pg.865]    [Pg.501]    [Pg.568]    [Pg.45]    [Pg.103]    [Pg.448]    [Pg.452]    [Pg.453]   
See also in sourсe #XX -- [ Pg.26 , Pg.190 , Pg.230 , Pg.346 , Pg.352 , Pg.384 , Pg.385 ]




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