セレン酸 化学特性,用途語,生産方法
解説
H2SeO4(144.98)．セレン酸はIUPAC命名法の許容する慣用名．付加方式命名法による体系名は，構造[SeO2(OH)2]に従ってジヒドロキシドジオキシドセレン(dihydroxidodioxidoselenium)．SeO2の水溶液をH2O2で酸化後，濃縮すると得られる．PbSeO4とH2Sとの反応などでも得られる．斜方晶系の結晶．正四面体型構造のSeO4が存在する．Oは互いにO-H…O結合をしている．Se-O1.61 Å．O-H…O 2.61，2.68 Å．融点58 ℃．260 ℃ で分解して，SeO2，H2O，O2になる．水に易溶．二，四，六水和物もつくる．硫酸に似てpK2 1.75(25 ℃)の強い酸で，脱水，有機物を炭化するなどの作用がある．硫酸より強い酸化剤で，HX(X ＝ Cl，Br，I)，H2S，ギ酸，シュウ酸，S，Pなどを酸化する．Ag，Au，Pdなども溶解する．「セレン及びその化合物」は毒物及び劇物取締法・毒物，化学物質排出把握管理促進法・第一種指定化学物質，労働安全衛生法・名称等を通知すべき危険物及び有害物．[CAS 7783-08-6]
森北出版「化学辞典（第2版）
化学的特性
colourless or white crystals
使用
Selenic acid is used as an oxidizing agent. Its derivative sodium selenate is used in the preparation of glass and animal feeds. It acts as an analytical reagent and also used for the preparation of other selenium salts such as gold(III) selenate. Further, it reacts with fluorosulfuric acid to get selenoyl fluoride.
一般的な説明
A white crystalline solid. Very corrosive to skin, eyes and mucous membranes. Corrosive to metal. Toxic by skin absorption and by ingestion.
空気と水の反応
Very hygroscopic. Soluble in water.
反応プロフィール
Selenic acid, LIQUID reacts exothermically with chemical bases (for example: amines and inorganic hydroxides) to form salts. The reactions can generate dangerously large amounts of heat in small spaces. A good oxidizing agent. May oxidize organic matter such as wood, cotton, fiberboard, etc.. Reacts with active metals, including iron and aluminum, and also less active metals, to dissolve the metal and liberate hydrogen and/or toxic gases. Can initiate polymerization in certain classes of organic compounds. Reacts with cyanide salts and compounds to release gaseous hydrogen cyanide. Flammable and/or toxic gases are also often generated with dithiocarbamates, isocyanates, mercaptans, nitrides, nitriles, sulfides, and weak or strong reducing agents. Additional gas-generating reactions occur with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), and even carbonates: the carbon dioxide gas from the last is nontoxic but the heat and spattering from the reaction can be troublesome. May often catalyze (increase the rate) of chemical reactions.
健康ハザード
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
火災危険
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
安全性プロファイル
Selenium compounds are poisons. A corrosive irritant to skin, eyes, and mucous membranes. When heated to decomposition it emits toxic fumes of Se. See also SELENIUM COMPOUNDS,
セレン酸 上流と下流の製品情報
原材料
準備製品