Arsenic trioxide, production

Antimony and compounds (as Sb) ANTU (a-naphthylthiourea) Arsenic and compounds (as As) Arsenic trioxide production (as As) Arsine Asbestos... 

Arsenic and soluble compounds, as As Arsenic trioxide production Arsine ... 

Including calculated arsenic trioxide equivalent of metallic arsenic and of arsenic compounds other than arsenic trioxide, where inclusion of such materials would not duplicate reported arsenic trioxide production. The table includes data available through May 25,1990. 

The refined arsenic trioxide is analysed for purity and also tested for solubihty, a term referring to its rate of reactivity with nitric acid this test is important if the arsenic is used in the manufacture of insecticides and herbicides. The product is graded for marketing as white soluble having 99% min AS2O2, white insoluble, or cmde having 95% min AS2O2. 

The predominant use of arsenic ia the United States is ia the manufacture of chemicals. During the 1980s, the market for arsenic chemicals had shifted from cotton farming, where its use is now restricted because of environmental considerations, to wood (qv) preservatives for the protection of lumber and other wood products. Arsenic trioxide is the basic commodity of commerce from which a number of important chemicals are manufactured. 

Until the late 1980s the United States was a principal suppHer of arsenic trioxide for domestic use. However, it must now rely entirely on imports. Table 4 gives the annual world production and United States imports of arsenic trioxide for the latter part of the 1980s. 

Table 4. World Production and U.S. Imports of Arsenic Trioxide ...

Arsenic By-product of copper and lead smelters Arsenic trioxide Baghouses or ESPs... 

Gollackner, B. et al., An exploratory investigation of the effect of arsenic trioxide on anti-Gal antibody production in baboons, Xenotransplantation, 10, 80, 2003. 

Iwama, K. et al., Apoptosis induced by arsenic trioxide in leukemia U937 cells is dependent on activation of p38, inactivation of ERK and the Ca2+-dependent production of superoxide, Int. J. Cancer, 92, 518, 2001. 

The product should be readily soluble in cold sodium carbonate solution. Otherwise arsenic trioxide, which can thus be removed, is present. 

The metallic arsenic is obtained primarily from its mineral, arsenopyrite. The mineral is smelted at 650 to 700°C in the absence of air. However, the most common method of production of the metal involves reduction of arsenic trioxide, AsOs with charcoal. Arsenic trioxide is produced by oxidation of arsenic present in the lead and copper concentrates during smelting of such concentrates. The trioxide so formed, readily volatilizes and is collected in a dust flue system where further treatment and roasting can upgrade the trioxide content. The trioxide vapors are then condensed and further purified by pressure leaching and recrystallization techniques. It is then reduced with charcoal to give metallic arsenic. 

Arsenic trioxide is obtained by roasting the mineral arsenopyrite, FeAsS, in air at 650 to 700°C. It is also obtained as a by-product during the smelting of... 

Oxidation in air at elevated temperatures form arsenic along with arsenic trioxide or arsenic pentoxide, the nature of the product depending on the arsine to oxygen ratio ... 

A solution of 7g of arsenic trioxide in 100ml of concentrated hydrochloric acid is mixed with a solution of 35g of potassium iodide in 35ml of water, After standing for 5 minutes tile orange precipitate of product Is filtered off, drained thoroughly, and dried in vacuo over solid alkali. The product is freed from adhering potassium chloride hy... 

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