ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 11, pp. 1869−1878. © Pleiades Publishing, Ltd., 2016.
Catalytic Conversion of Benzene to Phenol
M. K. Al Mesfer
, M. Danish
*, and S. M. Ahmed
Department of Chemical Engineering, King Khalid University, Abha 61411, KSA
Department of Chemistry, College of Science, King Khalid University, Abha 61411, KSA
Received November 6, 2016
Abstract—Phenol is very useful intermediate in the manufacture of petrochemicals, drugs, agrochemicals, and
plastics. Commercially, phenol is produced by a three-step, high-energy consumption process known as the
cumene process. The conversion of a chemical to a value-added product is always economically desirable. More
than 90% of phenol consumption in the world is manufactured by the multistep cumene process, in which ac-
etone is coproduced in 1 : 1 molar ratio with respect to phenol. However, the drawbacks of the three-step cumene
process have spurred the development of more economical routes to decrease energy consumption, avoid the
formation of explosive cumene hydroperoxide, and increase the yield. The objective of this article is to highlight
benzene-to-phenol conversion technologies with emphasis on direct conversion methods. Gas phase and liquid
phase reactions are the two main routes for direct oxidation of benzene to phenol. Indirect methods, such as the
cumene process, and direct methods of benzene-to-phenol conversion are discussed in detail. Also discussed is
the single-step reaction of benzene to phenol using oxidants such as O
O, and H
. Catalytic conversion
of benzene to value-added phenol using a chemically converted graphene-based catalyst, a cost-effective carbon
material, is discussed.
The text was submitted by the authors in English.
Phenol is one of the most valuable intermediates for
manufacturers and is used for the chemical synthesis
of drugs, petrochemicals, agrochemicals, and synthesis
resins. The global production of phenol is about 8 Mt/
year. The conversion of benzene to oxygen-containing
aromatics compounds, such as phenol, is one of the most
active areas in applied and fundamental catalytic research.
In industry, phenol is a crucial bulk commodity
chemical. Its production in the chemical industry is mainly
accomplished through the cumene method: a three-step
process in which acetone is produced as a by-product in a
molar ratio of 1 : 1, along with phenol as the main product.
More than 90% of the phenol consumed in the world
is produced by this three-step conversion process. The
salability of the by-product acetone decides the industrial
application of this multi-step process. However, the
cumene process has drawbacks, for example, high rates
of pollution, safety risks related to the explosive nature
of the intermediate (cumene hydroperoxide), high energy
consumption, expensive separation of the signiﬁ cant
amount of acetone as a by-product, and comparatively
little selectivity of the desired product.
Acetone is produced as a co-product during this three-
step process, which will lead to oversupply in the near
future; furthermore, the intermediate cumene hydroxide
can decompose violently. Because of the intrinsic
environmental and energy issues related to this process,
many attempts have been made to develop new methods
for phenol manufacturing through direct oxidation of
benzene. The transformation of arenes catalytically to
various functional chemicals is of signiﬁ cant interest
to the chemical and allied industries and remains a
challenging task for chemical engineers.
The development of an alternative process to the
cumene method is desirable for multiple reasons, among
them to minimize the formation of intermediate and to
increase the phenol selectivity. Therefore, single-step
conversion of benzene to phenol has been identiﬁ ed as a
potentially attractive alternative over the state of the art
due to economic incentive and environmental concerns.