삼산화 비소 C화학적 특성, 용도, 생산
개요
Arsenic trioxide, often denoted as As
2O
3 butmore correctly stated as As
4O
6, is an inorganic compound mainly
used as the precursor for organoarsenic compounds. It can be obtained by the oxidation of arsenic-containing
minerals in the air, such as roasting of orpiment.
2As
2S
3 + 9O
2 → As
4O
6 + 6SO
2
화학적 성질
WHITE POWDER AND FINE CHUNKS
용도
It is a reductometric standard.
정의
A colorless crystalline solid that is very poisonous (0.1 g would be a lethal dose). Analysis of the solid and vapor states suggests a dimerized structure of As
4O
6. An amphoteric oxide, arsenic(III) oxide is sparingly soluble in water, producing an acidic solution. It is formed when arsenic is burned in air or oxygen.
제조 방법
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 ofcopper and lead concentrates during the extraction of these metals from their ores that contain arsenic. The latter readily oxidizes to arsenic trioxide which is volatilized. The vapors are then condensed and collected. High purity-grade oxide can be obtained by resublimation of the crude trioxide or by pressure leaching and recrystallization. Arsenic trioxide may also be prepared by hydrolysis of arsenic trichloride, -tribromide or -trifluoride.
화학 반응
In the processing of As2O3 the oxide is normally reduced withcarbon:
2As2O3+3C?→As4+3CO2
The reaction is endothermic and is carried out at 500–800℃.The elemental arsenic sublimes and is condensed out of the reaction gas by cooling.
일반 설명
White or transparent, glassy amorphous lumps or crystalline powder. Slightly soluble in water, but dissolves very slowly; more soluble in hot water. Noncombustible. Corrosive to metals in the presence of moisture. Toxic by ingestion.
공기와 물의 반응
Slightly soluble in water, but dissolves very slowly; more soluble in hot water [Merck].
반응 프로필
Arsenic(III) oxide reacts vigorously with fluorine at ordinary temperatures [Mellor 9:34 1946-47]. Dissolves in aqueous acids. Incompatible with tannic acid, infusions of cinchona and other vegetable astringent infusions and decoctions, and with iron in solution [Merck].
위험도
A confirmed carcinogen.
건강위험
Material is considered super toxic; probable oral lethal dose (human) is less than 5 mg/kg, i.e., a taste (less than 7 drops) for a 70kg (150 lb.) person. Material causes acute gastrointestinal and central nervous system symptoms. Renal and hepatic damage have also been observed. Chronic exposure to material has led to nasal septum perforation, dermatological symptoms (lesions, necrosis, etc.) and an increase in the incidence of lung and lymphatic cancers. Appreciable exposure to respiratory irritant promoters such as metal oxide fumes elicits a carcinogenic response from Arsenic(III) oxide .
화재위험
Toxic fumes of Arsenic(III) oxide and arsine may be formed in fire situations. Contact with halide acids will form toxic volatile halides. Reduction in acid solutions will form arsine. Arsenic(III) oxide and excess zinc filings will explode on heating. Avoid sodium chlorate; fluorine; chlorine trifluoride; chromic oxide; aluminum chloride; phosphorus pentoxide; hydrogen fluoride; oxygen difluoride, tannic acid; infusion cinchona and other vegetable astringent infusions and decoctions; iron in solution. Arsenic(III) oxide is stable in air but slowly oxidizes in acid media.
Safety Profile
Confirmed human
carcinogen with experimental neoplastigenic
and tumorigenic data. Poison by ingestion,
subcutaneous, and intravenous routes.
Human systemic effects by ingestion: sleep
changes, muscle weakness, hypermotiltty,
darrhea, cardiac arrhythmias, coma, fatty
degeneration of the liver, depressed renal
function tests. An experimental teratogen.
Other experimental reproductive effects.
Mutation data reported. Reacts vigorously
with Rb2C2, CIF3, F2, Hg, OF2, NaClO3. See
also ARSENIC COMPOUNDS.
잠재적 노출
Arsenic trioxide, a primary raw material
for other arsenic compounds, is used in manufacture of
pesticides, glass, industrial chemicals, and drugs. It is an
intermediate for insecticides, herbicides and fungicides.
The material is used as a wood and tanning preservative
and a decoloring and refining agent in glass manufacture. It
is also used in pharmaceuticals and in the purification of
synthetic gas.
운송 방법
UN1561 Arsenic trioxide, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials
Purification Methods
It crystallises in an octahedral form (common form) from H2O or from dilute HCl (1:2), and is then washed, dried and sublimed (193o/760mm). Analytical reagent grade material is suitable for use as an analytical standard after it has been dried at 105o for 1-2hours or has been left in a desiccator for several hours over conc H2SO4. Alternatively: As2O3 (15g) is dissolved by heating in a mixture of H2O (60mL) and HCl (90g, s.g. 1.1), and crystallisation occurs on cooling, accompanied by brilliant flashes of light [Bandrowski Z Phys Chem 17 234 1895]. The amorphous form is a colourless transparent glass (m 200o) which is obtained when the vapour is slowly condensed below the vaporization temperature, and should be kept in a sealed tube because it changes to the octahedral form (m 275o) in the presence of moisture. [Rushton & Daniels J Am Chem Soc 48 384 1926.] A third monoclinic form, is obtained by heating the oxide in a sealed tube at 400o (the vitreous, amorphous form remains at the bottom of the tube) with the monoclinic form subliming onto the intermediate part of the tube at 200o (m 312o), and the octahedral form deposits at the top of the tube. The transition temperature between the last two forms is ~250o. POISONOUS (particularly the vapour, handle in a ventilated fume cupboard). [Schenk in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 600 1963.]
비 호환성
Sodium chlorate; sodium hydroxide, sulfuric
acid; fluorine; chlorine trifluoride; chromic oxide; aluminum
chloride; phosphorus pentoxide; hydrogen fluoride;
oxygen difluoride; tannic acid; infusion cinchona and other
vegetable astringent infusions and decoctions; iron in solution.
Contact with acids or acid mists releases deadly arsine
gas.
폐기물 처리
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform with EPA regulations governing
storage, transportation, treatment, and waste disposal.
Dissolve in a minimum of concentrated hydrochloric acid.
Dilute with water until white precipitate forms. Add HCl to
dissolve. Saturate with H2S; filter and wash precipitate and
return to supplier. Alternatively, precipitate with heavy
metals, such as lime or ferric hydroxide in lieu of H2S.
If needed, seek professional environmental engineering
assistance from the United States Environmental Protection
Agency Environmental Response Team at (908) 548-8730
(24-hour response line).
삼산화 비소 준비 용품 및 원자재
원자재
준비 용품
