Nitrification
Concentration
necessary to
Compound
Formula
:\lolecular
inhibit oxidation
weight
of ammonia by 75%
,-----~
mg/1
molarity
Thiourea
(NH2)1CS
76
0·076
x JO-I
Thioacetamide
CH,.CS.NH,
75
0·53
7
x w-1
Thiosemicarbazide
XH(NH,).CS.NH,
91
0·18
2
X I0- 1
:\ CH,.NCS
73
0·8
1·1 x w-•
Allyl isothiocyanatf'
CH 2 :CH.CH2.NCS
99
1·9
1·9 x w-•
Dithio-oxamidP
XH1.CS.CS.NH,
120
l·l
9·2 X J0-1
Potassium thiocyanatP
KCNS
97
30o•
3·1 X J0-10
Sodium methyl
f'H,.NH.CS.S Na
12!1
0·!1
7
X J0-1
rlithiocarbamatf'
Sodium dimethyl
i<'H,),.N.C'S.S Na
143
13·6
!Hi x w-•
dithiocarbamate
Dimethyl ammonium
dimethyldithio(CH,)2.N.CS.S.NH,(CH 3 ),
166
19·3
11·6 x w-•
carbamate
methyleneC,H,.NH.CS.S Na.2H,O
21!1
23
10·5 x w-•
dithiocarbamatf'
pentamethyleneC,H,.NH.CS.S.NH,C,H,,
246
fl7
2·3 x w-•
dithiocarbamat-f"
:\!ethyl thiuronium
[NH,.C(: NH).S.CH,],H,SO,
278
6·5
2·3 x w-•
sulphate
Benzyl thiuronium
[NH,.C(: NH).S.CH 2(C,H,)]HC1
203
49
2·4 x w-•
chloride
Tetramethyl thiuram
(CH,),.N.CS.S.C'S.N(CH,),
208
16
7·5 x w-•
mon011ulphide
Tetramethyl thiuram
(CH1)1.N.CS.S.S.CS.N(CH,),
240
30
1·2 x to-•
disulphide
Mercaptobenzothiazole
C,H,.SC(SH):N
167
3
1·8 x w-•
Benzothiazolp
C10H,N,S,
332
38
1·2 x to-•
dumlphirlP
Pho.nol
C1H 6.0H
94
5·6
6
x w-•
o-cresol
CH,.C1H 1.0H
107
12·8
1·2 x w-•
m-cresol
CH,.C1H,.OH
107
11·4
1·06 x 10·•
p-cresol
CH,.C,H,.OH
107
16·.';
1·53x to-•
Aniline
C,H,.NH,
93
7·7
8·3 x to-•
2-4 dinitrophenol
C,H,(NO,),
184
460
2·5 X I0-3
Allyl alcohol
CH,:CH.CH,OH
58
19·5
3·4 x w-•
Allyl chlori CH,:CH.CH,CI
76·.i
180
2·4 X lQ-3
Di-allyl ether
iCH,:CH.CH,),O
98
100
I
x w-•
Sodium cyanide
NaCN
27
0·6S
2·4 x w-•
Dimethyl p-nitroso(CH,)1N.C,H,.NO
150
19
1·3 x w-•
anilinP
011anirline carbonatR
[(NH1)1.C: NH]H1C0 3
180
16·5
!1·2 x w-•
Diphenyl guanidine
(NH.C,H 6)1.C:NH
211
50°
2·5 xiO-'*
Diguanide
NH,.C(: NH)NH.C(: NH)NH,
101
50
5
x to-•
Dicyandiamide
NH,.C( :NH)NH.CN
84
250
3
X IO-•
Skatole
C,H,NHCH:CCH,
131
7·0
5·3 X IO-•
Strychnine
hydrochloride
2-chloro-6C11H 110 1N 1.HCI.2H,O
407
175
4·3 x w-•
trichloromethylC,H,NCl(CC13)
231
100
o-43 x w-•
pyridine
Ethyl urethane
NH1.CO.OC,H,
89
1,780
2
X IO-•
EDTA
[(COOH.CH,),.N.CH,],
292
350*
1·2 x w-••
Hydrazine
NH1.NH1
32
58
1·8 X to-•
Methylamine
CH1.NH,HC1
67·5 1,550
2·3 x w-•
hydrochloride
Trimethylamine
N(CH,),
59
liS
2
X to-•
Sodium azide
NaN,
65
23
3·6 X 10-•
Methylene blue
C11H 11N 1SCI.3H,O
373-5
too•
3
xlO-'*
Carbon disulphide
cs,
76
35
0·46 X to-•
Ethanol
C,H,OH
46
2,400
5
X to-•
Acetone
CH,.CO.CH,
58
2,000
3·5 X to-•
Chloroform
CHCI,
ll9·4
18
1·5 x w-•
8-hydroxyquinoline
C,H,N.OH
145
72·5
5
x w-•
Streptomycin
c .. H,,N,011
581·6
400*
6·9 X to-••
• Highest concentration tested, but not effective.
Table3.9
Inhibition of nitrification. From /22/.
84