Nitrates 化学特性,用途語,生産方法
世界保健機関(WHO)
Glyceryl trinitrate (nitroglycerin) and isosorbide dinitrate are
listed in the WHO Model List of Essential Drugs.
农业用途
Nitrates, a combination of nitrogen and oxygen, are salts
of nitric acid and metals. When used as fertilizers,
nitrates are generally salts of ammonium, sodium,
potassium and calcium. Nitrates are monovalent ions
used as fertilizers, either individually or as mixtures.
Most nitrates are water-soluble and when applied to the
soil as a fertilizer, are easily leached out because of their
weak binding to soil particles.
Because nitrate contains nitrogen in its highest
oxidation state (+5), it is a useful oxidizing agent and is
often a constituent of matches and explosives. Leaching
of nitrates causes low efficiency of nitrogen use.
Principal issues relating to nitrates are: (a) surface water
eutrophication, (b) increased production of nitrous
oxide from the received waters, and (c) increased nitrate
concentration in drinking water.
The excess of nitrate in drinking water is harmful.
The allowable limit of nitrates in Europe is 50 mg/liter.
The upper limit is set, particularly, to protect infants
from the possible risk of acute methemoglobinemia (blue
baby syndrome), arising from their consumption of water
containing excess nitrates. If excessive nitrates get
consumed, the nitrite (NO
2-) reacts with food
components in the stomach and can give rise to
carcinogenic nitroso compounds.
A plant gets the required nitrogen for its growth
mostly as nitrate (NO
3-) and partly as ammonium
(NK
4+). The nitrate uptake is high in acidic soil. Under
anaerobic conditions, micro-organisms reduce nitrates to
nitrites, then to ammoniacal salts and finally to gaseous
nitrogen which is lost to the atmosphere.
安全性プロファイル
Large amounts taken by
mouth may have serious or even fatal
effects. The symptoms are dzziness,
abdominal cramps, vomiting, bloody
diarrhea, weakness, convulsions, and
collapse. Small, repeated doses may lead to
weakness, general depression, headache, and
mental impairment. Also, there is some implication of increased cancer incidence
among those exposed.
Flammable by spontaneous chemical
reaction; practically all nitrates are powerful
oxidzing agents. Some nitrates may explode
when shocked, exposed to heat or flame, or
by spontaneous chemical reaction (see also
EXPLOSIVES, HIGH). All the inorganic
nitrates act as oxygen carriers; under proper
condtions, these can give up their oxygen to
other materials which may in turn detonate.
Ammonium nitrate has all the properties of
the other nitrates, but it is also able to
detonate by itself under certain conditions.
It is therefore a high explosive, although
very insensitive to impact and difficult to
detonate. In the pure state, it requires a
combination of an initiator and a high
explosive. It is a relatively safe high
explosive, which, however, must be stored
in a cool, ventilated place away from acute
fire hazards and easily oxidized materials.
Ammonium nitrate must not be confined
because, if a fire should start, confinement
can cause detonation with extremely violent
results.
Violent reaction with Al, BP, cyanide,
esters, PN2H, P, NaCN, SnCl2, sodum
hypophosphte, thocyanates. Dangerous
disaster hazard due to fire and explosion
hazard. When heated to decomposition it
emits toxic fumes of NOx. They are
powerful oxidizing agents that may cause
violent reaction with reducing materials.
Nitrates should be protected carefully in
storage.
Nitrates 上流と下流の製品情報
原材料
準備製品