けいそう土 化学特性,用途語,生産方法
外観
白色～褐色, 粉末
定義
本品は、種々のケイソウの遺ガイから成るケイ酸質の堆積物である。
溶解性
水にほとんど溶けない。
解説
おもにけいそうの殻からなる軟質岩石．けいそう殻はSiO294％，H2O6％ 程度であるが，けいそう土は不純物を含むほか，二次的沈殿物を含む．海成と淡水種があり，後者が良質である．カナダ，オーストラリア，ドイツ，アフリカに産出する．日本では秋田，宮城，石川，岡山，大分の各県に産出する．多孔質で，この特性をいかして，濾過助剤，吸収剤，保温剤などに，また研磨材，れんがに利用される．
森北出版「化学辞典（第2版）
用途
吸着剤、ろ過剤、保温材、研磨剤
用途
断熱材、ろ過助剤
用途
合成反応液の分配抽出、水分除去用。
化粧品の成分用途
不透明化剤、抗ケーキング剤、吸着剤、研磨.スクラブ剤、増量剤
特長
カラム内で液-液抽出が可能な特性を持っているため、従来分液ロート又は試験管等で行っていた抽出操作を短時間にしかも簡単に行うことができる。
化学的特性
white to off-white powder
使用
Diatomaceous earth may be used as an adsorbent for column chromatography.
一般的な説明
Chromosorb
? W is a diatomite which provides solid support for the packed GC columns. It is suitable for use with polar compounds, due to its low surface area and high inertness.
健康ハザード
Amorphous silica, natural
diatomaceous earth, is usually considered to be
of low toxicity; however, pure amorphous silica
is rarely found.
職業ばく露
Amorphous fumed silica is used as a mineral, natural or synthetic fiber. A potential danger to those involved in the production and handling of fumed silica for paint pigments or catalysts. Diatomaceous earth is used in clarifying liquids, in manufacture of fire brick and heat insulators; used as a filtering agent; as a filler in construction materials; pesticides, paints, and varnishes. A potential danger to those involved in mining of diatomaceous earth or fabrication of products there from.
発がん性
Amorphous silica has been tested for carcinogenicity
in a variety of animal studies by a
number of routes. Most of the tests were negative
or were inadequate primarily because of
poorly defined physiochemical characteristics
of the silica. The IARC concluded that evidence
is inadequate to describe amorphous
silica as carcinogenic in either experimental
animals or humans. Crystalline silica, however,
has been designated by IARC as a probable
human carcinogen (category 2A), based on
“sufficient evidence” in experimental animals
and “limited evidence” in humans.Therefore,
although evidence for the carcinogenicity
of crystalline silica in humans is unconvincing,
certainly from exposures insufficient to cause
silicosis, appropriate hazard warnings are
obligatory in the United States. These apply
to all materials containing 0.1% or more of
crystalline silica (quartz, cristobalite, and/or
tridymite).
不和合性
Silica, amorphous is a noncombustible solid. Generally unreactive chemically. Incompatible with fluorine, oxygen difluoride, chlorine trifluoride. Soluble in molten alkalis and reacts with most metallic oxides at high temperature.
廃棄物の処理
Sanitary landfill.
けいそう土 上流と下流の製品情報
原材料
準備製品