ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 4, pp. 539!543. + Pleiades Publishing, Inc., 2006.
Original Russian Text + V. S. Kolosnitsyn, S. P. Kosternova, O. A. Yapryntseva, A. A. Ivashchenko, S. V. Alekseev, 2006, published in Zhurnal Prikladnoi
Khimii, 2006, Vol. 79, No. 4, pp. 551!555.
AND INDUSTRIAL INORGANIC CHEMISTRY
Recovery of Nickel with Sulfuric Acid Solutions
from Spent Catalysts for Steam Conversion of Methane
V. S. Kolosnitsyn, S. P. Kosternova, O. A. Yapryntseva,
A. A. Ivashchenko, and S. V. Alekseev
Ishimbai Branch of Ufa State Technical University of Aviation, Ishimbai, Bashkortostan, Russia
Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, Ufa, Bashkortostan, Russia
PALLAD NPF, Salavat, Bashkortostan, Russia
Received May 6, 2005; in final form, December 2005
Abstract-Certain fundamental aspects of leaching-out of nickel with sulfuric acid solutions from spent
catalysts for steam conversion of methane under static and dynamic conditions were studied.
At present, a considerable attention is given to
the problem of utilization and processing of solid
wastes containing nonferrous metals. Wastes of this
kind are toxic substances hazardous to the environ-
ment, on the one hand, and a valuable chemical raw
material, on the other.
A widely occurring type of solid wastes from pet-
rochemical and oil refining industries are spent cat-
alysts, including nickel3alumina catalysts for steam
conversion of methane. In the course of operation,
the catalysts lose activity as a result of changes in
their composition and structure. At high temperatures
(6003700oC), the catalyst undergoes sintering and its
active surface area decreases.
In the course of time,
a considerable fraction of nickel cations diffuses from
the catalyst surface deep inside alumina, active nickel
oxide is converted on alumina into inactive nickel
aluminate, and spinel-like compounds, inactive in
catalysis, are formed [1, 2].
In some cases, deactivated catalysts are regenerated,
but this cannot be done for a large number of cat-
alysts. They are removed from the process and re-
Commonly, two methods are suggested for recov-
ery of nickel from ores and raw materials of tech-
nological origin: pyrometallurgical technique, whose
main product is ferronickel obtained at high tempera-
tures, and hydrometallurgical, based on leaching-out
The temperature of steam conversion of methane is 800oC.
of nickel from raw materials with various acids and
solutions of ammonia and ammonium salts.
The use of ammonia for leaching-out of nickel
relies on the fact that nickel hydroxides readily react
with ammonia to give stable complexes of various
compositions. This circumstance serves as a basis
for recovery of nickel from oxidized ores , spent
catalysts , and worked-out electrodes of nickel3iron
batteries [5, 6]:
It was found that addition of ammonium salts to
aqueous solutions improves the efficiency of dissolu-
tion via the buffer action precluding accumulation of
Cl 6 [Ni(NH
It has been suggested to leach-out nickel from ox-
ide raw materials with solutions of (NH
and with mixtures of these at pH 63 8 :
NiO + (NH
OH 6 [Ni(NH
Leaching-out of nickel from ores and raw materials
of technological origin with solutions of mineral acids
was suggested in .
However, the leaching methods described in the lit-
erature have certain disadvantages. For example, the