New " standard of sanitation of life drinking water " GB5749-2006 project unscra
From;    Author:Stand originally
Keyword: Life drinking water formaldehyde structural formula

1 overview
 

1. 1 fundamentality is qualitative
Americanization learns abstract (CA) number
500-00-0
IUPAC is right of formaldehyde name for " Methanal " .

Structural formula
CH2O
Manage changes character
 

Natural state

Colorless gas

Boiling point ℃

- 19.2

Melting point ℃

- 118

Relative to density

1.04(air is 1)

Vapour pressure

52.6kPa(-33 ℃ )

Water-solubility (G/l)

In 25 ℃ and dissolve of water each other

Xin Chun - the logarithm of the distribution coefficient in water

- 1

Note: Palm  fetterses ǘ like that feng4huang2 is contrary to?ppm=1.2mg / M3(25 ℃ )
 

Formaldehyde stimulates a gender, resemble the odour like hay and wheat stalk stiflingly. Flavour threshold value and smell threshold value are respectively 50 with 25mg/L
 

1. 2 main use
The industrial use with main formaldehyde is to use at Niao one formaldehyde, phenolic kind, 3 get together 4 alcohol mix cyanogen amine, Ji Wu get together shrink aldehyde resinous production: Its the 2nd big utility is to be used in the industrial synthesis of a lot of kinds of organic matter. Formaldehyde still can be used in cosmetic, antiseptic, textile and perfume. Its common weighs aqueous solution of 10 % pH indicator " formalin " . It is animal, floral anticorrosive last agent
1. 3 analysises method
With 2, 2 nitrobenzene hydrazine derive 4- , after solid fluid is extractive, HPLC determines. Detect be restricted 6. L of / of 2 μ G.
 

2 environments level and human body absorb a way
 

2.1 air
Armour is passed plastic reach fluid of synthetic resin glue to enter air. The low content in air also by the carbon that derives from fossil fuel - the smooth oxidation of hydrogenous compound arises. Typical chroma is M3 of / of G of a few μ in air. The person that smoke can absorb formaldehyde of tall pH indicator.

2. 2 water

The origin of the formaldehyde in drinking water basically is industrial waste water discharge and in water natural and organic matter (humus) change in ozone, the child of the oxidation in chloridize process. Organic matter solves the formaldehyde that can produce certain amount through heat in water. The person such as Yamada considers to point out heat can make content of the formaldehyde in water increases, in normally content of the formaldehyde in drinking water is 0, 24. L of / of 0 μ G, the chroma after boil increases for 18. 0- - 73. L of / of 5 μ G, and the exterior water via ozonation, it is before boil 10. O- - 110 μ G/L, add after boil to L of / of 21.O-243 μ G, problem of content of the formaldehyde in concerned mineral water also has news. Formaldehyde also is met from get together shrink dissolve of fittings of aldehyde resinous aqueduct drenchs come down.
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