Chamber acid

Chemical Designations - Synonyms Battery acid Chamber acid Fertilizer acid Oil of vitriol Chemical Formula H2SO4. 

Reactions with sulfides, polysulfides, sulfur oxides and the oxoacids of sulfur are complex and the products depend markedly on reaction conditions (see also p. 745 for blue crystals in chamber acid). Some examples are ... 

Squire and Messel An early process for making oleum from sulfuric acid produced by the Chamber process. The acid was decomposed at red heat to sulfur dioxide, oxygen, and steam the steam was condensed out, and the remaining gases passed over platinized pumice to form sulfur trioxide, which was absorbed in more chamber acid. Invented by W. S. Squire and R. Messel in 1875 in London and first commercialized there. Messel was one of the founders of the Society of Chemical Industry and is still commemorated in that society by the biennial award of a medal. 

The limit of concentration attainable by any of the foregoing methods is about 98 per cent. If acid of higher concentration than this is required, acid of 97 to 98 per cent, strength can be partially frozen,2 when the colourless prisms which separate contain 99-5 to 100 per cent. H2S04 and constitute the frequently so-called, but misnamed, monohydrate. Owing to the success of the contact process for the preparation of sulphur trioxide and of fuming sulphuric acid, the production of highly concentrated sulphuric acid has been rendered so simple a matter that concentration of the lead chamber acid is of diminished importance. The main value of the chamber process lies in its economical production of a not necessarily very concentrated acid. There are indications, however, that by a suitable combination of the two processes, an even more economical production of concentrated acid may be obtainable (see p. 162). 

The dilute sulfuric acid is drained from the chambers it contains 60 to 65% H2S04. This acid is normally used at this concentration. Although there are several inconvenient and somewhat costly processes for concentrating the lead-chamber acid, it is difficult to concentrate this product economically in view of the ease with which concentrated sulfuric acid may be produced directly by the contact process. 

The lead-chamber process is more economical than the contact process, but it produces a more dilute and less pure product. Thus, the chamber process can compete only in the market that can use a relatively impure and dilute acid. Although chamber-acid plants now in use will undoubtedly be operated for many years to come, it seems probable that all sulfuric acid plants constructed in the future will employ the contact process or some still more efficient process. 

The utilization of tricalcium phosphate therefore requires its conversion into a soluble salt. This is accomplished by treating the normal phosphate with dilute sulfuric acid (lead-chamber acid), thereby producing the soluble primary calcium phosphate ... 

Modifications of the process include towers to recover excess nitrogen oxides and to increase the final acid concentration from 65% (chamber acid) to 78% (tower acid). 

Synonyms Battery acid, Chamber acid, Contact acid, Dipping acid, Fortifying acid, Hydrogen sulfate, Oil of Vitriol, Tower acid, Vitriolic acid. 

Sulfuric acid Battery Acid Chamber Acid Fertilizer Acid Oil of Vitriol ... 

SYNONYMS battery acid, chamber acid, fertilizer acid, hydrogen sulfate, oil of vitriol, sulfuric acid (aqueous). 

The acid is allowed to collect in the chambers until it has the sp. gr. 1.55, when it is drawn off. This chamber acid, although used in a few industrial processes, is not yet strong enough for most purposes. It is concentrated, first by evaporation in shallow leaden pans, until its sp. gr. reaches 1.746. At this point it begins to act upon the lead, and is transferred to platinum stills, where the concentration is completed. 

Chamber Acid Charcoal Chem BAM Chinese Tannin Chinoline Chloracetic Acid Chloracetyl Chloride Chlorate of Potash Chlorate of Potassium Chlorate of Soda Chlordan Chlordane 2-Chlorethanol Chlorex... 

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