9
86
PAVELKO
created a lower energy load on pyrite than steel balls. In
Another distinctive feature of mechanochemical
a steel reactor, H S and S were detected in the reaction reaction of pyrite with water in a quartz ampoule (run 24)
2
8
2
–
of pyrite with deficient water; S could result from oxi-
8
is the absence of SO in filtrate.
3
dation of activated pyrite after depressurizing the reac-
tor or during extraction of wet pyrite with benzene.
To summarize, having studied mechanochemical
reactions of S and iron sulfides with hydrogen, oxygen,
8
From the results of qualitative analysis of the aque- and water, we discovered three new reactions occurring
ous solution produced by FeS dispersion in excess at room temperature in which H S is generated by
2
water, it follows that FeS virtually did not react with
water in an deoxygenated medium (run 15). After
mechanochemical reaction of pyrite with water (run 24)
under similar conditions, the solution contained the fol-
schemes (1), (2), and (4). We have shown that H S par-
2
ticipates in mechanochemical synthesis of FeS from the
constituent elements in water. We have also shown that
S8 is formed during mechanochemical oxidation of
pyrite by dioxygen during or after dispersion. Pyrite
reacts with water even in the absence of oxygen. FeS
virtually does not react with water under similar condi-
tions. Pyrite reacts with dihydrogen and water in deox-
ygenated media directly, avoiding dissociation by
scheme (5) or (12).
2+
lowing compounds: H (0.02 mL or 0.4 vol %), Fe
2
2
–
2–
3+
(
plenty), Fe (traces), SO (plenty), and S O (lit-
4 3
2
tle). Elementary sulfur and H S were not detected. This
2
means that pyrite reacts with water directly, as with iron
[7] and hydrogen.
Gusev and Molchanov [23] studied the products of
dispersion of iron sulfides in water by means of a plan-
etary mill inside a copper reactor with copper shot,
apparently, in an air atmosphere. They believed that
oxidation of sulfide sulfur can be described as follows:
REFERENCES
1
. Investigations of Oils and Petroleum Products. Col-
lected Works, Ed. by L. A. Potolovskii (Gostoptekhizdat,
Moscow, 1955), p. 264 [in Russian].
2
3
. A. K. Dmitriev, Zh. Obshch. Khimii 18 (7), 1267 (1948).
. F. P. Treadwell, Tables for Qualitative Analysis (Gos.
Izd–vo, Moscow/Leningrad, 1930) [in Russian].
. G. M. Gusev, in Mechanochemical Phenomena in
Ultrafine Milling. Collected Works, Ed. by V. M. Klya-
rovskii andV. I. Molchanov (Nauka, Novosibirsk, 1971),
p. 110 [in Russian].
6
FeS + 29H O
2Fe O
3 4
2
(
(
18)
19)
+
3H SO + 3H SO + 23H ,
2
3
2
4
2
4
3
FeS + 25H O
Fe O
3 4
2
2
+
3H SO + 3H SO + 19H .
2 3 2 4 2
5
6
. F. C. Thompson and N. Tilling, J. Soc. Chem. Ind. 43 (9),
3
7 (1924).
. E. N. Isakov, Zh. Prikl. Khim. 12 (3), 388 (1939).
X-ray powder showed that magnetite was the major
component of the solid phase. After 30-min dispersion
of FeS and pyrite in water, 21.52 and 5.65 vol % hydro-
gen were, respectively, found in the reactor atmosphere.
After FeS dispersion, filtrate contained 0.024 g/L
7. E. G. Avvakumov, O. I. Samarin, and V. G. Kulebakin,
Izv. Sib. Otd. Akad. Nauk SSSR, Ser. Khim., No. 3, 29
(1981).
8. J. J. Berzelius, Pogg. Ann. 7, 393 (1826).
9
2
4
–
. W. F. Hillebrand, G. E. F. Lundel, H. A. Bright, and
J. I. Hoffman, Applied Inorganic Analysis with Special
Reference to the Analysis of Metals, Minerals, and Rocks
SO ; after pyrite dispersion, it contained 0.0074 g/L
2
3
–
2–
SO and 0.032 g/L SO4 were found. The hydrogen
index of these filtrates was definitely acidic.
(Wiley, NewYork, 1953; Goskhimizdat, Moscow, 1967).
1
0. B. I. Chufarov and B. D. Averbukh, Zh. Obshch. Khim.
Thus, a distinctive feature of mechanochemical dis-
19 (5), 857 (1949).
persion of iron sulfides in degassed water in quartz 11. V. I. Samgunov, B. M. Reingol’d, and V. I. Molchanov,
ampoules (runs 15 and 24) is that FeS, unlike pyrite,
virtually does not react with water. Possibly, this is
Izv. Sib. Otd. Akad. Nauk SSSR, Ser. Khim., No. 12, 135
1973).
(
because of the lower energy load on quartz balls as 12. A. N. Buckley and R. Woods, Appl. Surf. Sci. 27 (4), 437
compared to the energy load created by copper shot in
(1987).
a copper reactor. It is noteworthy that FeS in thermo- 13. P. Balaz, T. Havlik, Z. Bastl, and J. Briancin, J. Mat. Sci.
chemical interaction with water vapor was also less
Lett. 14, 344 (1995).
reactive than pyrite [5]. For example, FeS starts to react 14. J. Z. Jiang and R. K. Larsen, R. Lin, et al., J. Solid State
with water vapor at ~900 °ë by the following scenario:
Chem. 138 (1), 114 (1998).
1
5. E. G. Avvakumov, V. V. Boldyrev, and I. D. Kosobudskii,
Izv. Sib. Otd. Akad. Nauk SSSR, Ser. Khim., No. 9, 45
3
FeS + 4H O
Fe é + 3H S + H ,
(20)
2
3
4
2
2
(1972).
FeS reacts at 380°ë:
2
16. E. G. Avvakumov, V. V. Boldyrev, I. D. Kosobudskii, and
Yu. T. Pavlyukhin, Izv. Sib. Otd. Akad. Nauk SSSR, Ser.
Khim., No. 12, 132 (1973).
3
FeS + 2H O
2FeS + 2H S + Sé .
2 2
(21)
2
2
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 53 No. 7 2008