вход по аккаунту


Book Review Chemicals from Coal New Processes (Series Critical Reports on Applied Chemistry Vol. 14). Edited by K. R

код для вставкиСкачать
An Introduction to Chemisorption and Catalysis by Metals.
By R . P. H . Gasser. Oxford Science Publishers, Clarendon Press, Oxford 1987. xii, 260 pp., paperback,
L 12.95.-ISBN 0- 19-855271-8
To write an introduction to chemisorption and catalysis
by metals at the present time is no easy task, in view of the
rapid developments occurring in this field. The author of
this book avoids these difficulties by confining himself to
an account of long-accepted facts, well established methods, and only one example of a heterogeneously catalyzed
reaction. He deliberately excludes any discussion of the
theory of the bonding of molecules to the surface.
The book begins with a brief description of the interaction between the adsorbate and the surface and the thermodynamics of adsorption (isotherms, isobars and heats of
adsorption), such as one finds in other books of a similar
kind. The reader is then prepared for the chapters which
follow by a useful account of the primary processes that
occur during collision (elastic and inelastic processes, energy exchange). A longer chapter is devoted to the kinetics
of adsorption and desorption, including especially a discussion of sticking probability and of temperature programmed thermal desorption.
Next a short introduction to the structure of metals and
surfaces, the real and reciprocal lattices, the use of the
Ewald sphere, and the behavior of electrons in metals
leads into an essentially qualitative treatment of low energy electron diffraction. Under the heading “Electron emission’’ is given a 31-page account of ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), field electron microscopy and field ion microscopy. This chapter
certainly does not d o justice to the present-day importance
of these techniques. For example, in the treatment of UPS
we find no mention of the important information that can
be obtained by using polarized radiation or by measuring
the angular dependence. Similarly the ways in which XPS
and AES can be used are only briefly touched on. The
most recent developments in field emission are not included.
The treatment of chemisorption concludes with a very
brief section on modification of work functions, infrared
spectroscopy and high resolution electron energy loss
spectroscopy (H REELS).
Heterogeneous catalysis is introduced by referring to the
theory of the transition state, and discussing selectivity and
the relationship between strength of chemisorption bonding and catalytic activity; rate equations are derived for
reactions involving the Langmuir-Hinshelwood and the
Eley-Rideal mechanisms. The principles are illustrated by
reference to the ortho-para interconversion in hydrogen
and to hydrogen-deuterium exchange.
In a concluding chapter, as an example of the application of the methods described in the previous chapters, the
catalytic oxidation of carbon monoxide on palladium and
platinum is discussed with reference to model reactions
under high vacuum conditions.
Anyone working in the area of adsorption and catalysis
will find few new ideas in this book. New techniques
which have been developed in the last few years, such as
those which have become possible by using synchrotron
radiation, inverse photoemission, tunneling microscopy,
Angew. Chem. Inf. Ed. Engl. 27(19U8) No. 10
ion scattering and many others are not mentioned. The bibliography consists mainly of references to monographs
and review articles; it covers publications up to 1981, and
is thus not very up-to-date. However, the readership aimed
at by the author is not the expert one mentioned above.
The book originated from an introductory lecture course,
and is intended for students who have mastered the fundamentals of physical chemistry and now wish to study special topics, in this case that of adsorption as the primary
step in heterogeneous catalysis. These readers will find the
book useful. As a textbook to accompany a course such as
that mentioned it is an appropriate choice, being clearly
presented, adequately illustrated, and concentrating on the
Gerd Wedler [NB 913 IE]
Institut fur Physikalische und Theoretische Chemie
der Universitat Erlangen-Nurnberg (FRG)
Chemicals from Coal: New Processes (Series: Critical Reports on Applied Chemistry, Vol. 14). Edited by K . R .
Payne. Wiley, New York 1987. 114 pp., bound,
$50.30.--ISBN 0-471-91325-1
The book “Chemicals from Coal: New Developments”
appeared in 1985 as Volume 9 in the series “Critical Reports on Applied Chemistry”. That first 122-page volume,
edited by K . R . Payne, contained three articles: J. Schulze
(Technische Universitat Berlin) and H . Gaensslen (Lurgi
GmbH) discussed the economics of coal conversion processes, and in the two following articles J. 0. H . Newman
and G . 0. Dauies of the National Coal Board (Great Britain) reported on possibilities and recent advances in obtaining chemical feedstocks from coal by pyrolysis or direct liquefaction. The same editor (but a different publisher) has now produced the book under review here, as Volume 14 of the series, under the very similar title “Chemicals from Coal: New Processes”. In this volume the discussion of chemical feedstocks from coal is taken further, with
five articles on coal gasification, synthesis gas chemistry,
Fischer-Tropsch syntheses and the production of acetylene from calcium carbide.
In the first chapter, “Syngas via coal gasification”, B.
Cornils, formerly of Ruhrchemie and now with Hoechst,
reviews the present state of the art in coal gasification technology. Starting from the thermodynamic and kinetic relationships, and the existing first-generation gasification
processes (the Lurgi, Winkler, and Koppers-Totzek gasifiers), the discussion proceeds to the modern second-generation processes, some of which are still at the development
stage. The process engineering principles of fixed bed,
fluidized bed and entrained bed gasification processes, as
well as the differences between the many new developments which are competing with each other, are clearly explained. As a possible third-generation process, the allothermal fluidized bed gasification using process heat from
a high temperature nuclear reactor is discussed. This chapter is a concise but successful review of the topic by a competent author who was for some years involved in the advanced development of the Texaco gasification process.
In the second chapter, “Chemicals from coal via the carbide route”, F.- W. Kampmann and W. Portz of Knapsack/
Hoechst describe the production of acetylene via calcium
carbide. Only the manufacture of the carbide is described
in detail. The reader learns that since 1962 the production
of carbide has greatly declined throughout the world; regrettably, though, he is not told about alternative routes to
acetylene, such as by partial combustion of hydrocarbons,
by the Hiils process in which hydrocarbons undergo conversion in a plasma arc torch, or by similar attempts to
produce acetylene in the plasma directly from coal.
Chapter 3, “Catalysis in the conversion of synthesis gas
to chemicals”, by I . Wender, and Chapter 5, “Syngas
chemistry to chemical feedstock: New frontiers”, by B.
Cornils, are the most informative ones for the chemist interested in C1 chemistry. The two chapters overlap to some
extent in the topics covered, but on the other hand they
complement each other through their different viewpoints
and in the literature cited. Wender, formerly at the Pittsburgh Energy Technology Center and now an emeritus
professor at the University of Pittsburgh, generally discusses methods of catalyzing reactions of carbon monoxide and C, compounds. Accordingly the conversion of methanol using zeolites, and the acid catalyzed Koch-Haaf
synthesis of carboxylic acids from carbon monoxide, olefins and water, are addressed as well as the many different
catalytic reactions using heterogeneous and homogeneous
transition metal catalyst systems. Some of the reaction
schemes given here for catalytic cycles do not quite correspond to the presentations found in modern textbooks of
organometallic chemistry, but this does not detract from
the value of the information collected together in the review. Cornils limits his discussion to recent developments
in C , chemistry, such as the production of C, to C, olefins
using modified Fischer-Tropsch syntheses, the dehydration of methanol using zeolites, and methods for directly
synthesizing carboxylic acids, acetaldehyde, ethanol or
ethylene glycol from synthesis gas. As alternatives to such
direct manufacturing routes from synthesis gas, multistage
processes via methanol, acetic acid, formaldehyde or oxalic acid esters as intermediates are also discussed. Further
possibilities for using C, compounds as building blocks in
synthetic routes to methyl methacrylate, vinyl acetate, styrene, heterocyclic compounds, urethanes, acrylonitrile and
long chain unbranched fatty acids are also indicated.
In Chapter 4, “The Fischer-Tropsch synthesis as a
source of raw materials for the chemical industry”, M . E.
Dry describes the South African plants in Sasolburg and
Secunda which operate the Fischer-Tropsch synthesis.
Compared with other similar articles by the same author,
this review emphasizes the different spectrum of products
obtained from the two variants of the Sasol process using
fixed bed reactors and circulating fluid bed reactors, and
the downstream industrial processing of the mixture of
products obtained.
New processes for making chemicals from coal were
promised in the title of the book. The reader learns something of these in Chapters 1,3 and especially 5, but little in
Chapters 2 and 4. Apart from a very few exceptions, the
literature cited does not extend beyond 1984; as is unfortunately so often the case, this appears to be due to the long
delay between the completion of the manuscript and the
publication of the book.
For chemists and chemical engineers who wish to familiarize themselves with synthesis gas and C l chemistry, the
book is quite useful. So long as oil and natural gas continue to be cheaply available in sufficient quantities, processes based on coal will scarcely be economic. However,
the present situation in energy markets cannot blind one to
the fact that eventually it will become necessary to make
greater use of coal. The route via coal gasification and synthesis gas chemistry which is discussed here as a way of
producing chemical feedstocks appears very promising.
Finally, a comment on the short preface by the editor:
This reviewer, who happens to work in the laboratories
where Franz Fischer did his research, was surprised by the
following sentence: “The Fischer-Tropsch process was
originally developed in Germany by BASF before the First
World War, and was improved over the years until, by the
advent of World War 11, it became an important source of
chemicals and fuel for the Third Reich.” The 1913 BASF
patent D.R.P. 293 787, which first described the formation
of saturated and unsaturated hydrocarbons and of oxygencontaining compounds from synthesis gas at high pressure,
was certainly one of the starting points which in 1922
prompted Fischer and Tropsch at the Kaiser-Wilhelm-Institut in Miilheim to carry out their work on “Synthol”, a
mixture consisting mainly of oxygen-containing compounds. Franz Fischer himself confirmed this fact in a controversy with Alwin Mittasch (Angew. Chem. 40 (1927) 164
and 166). Systematic investigation of the reaction conditions led in 1925 to a hydrocarbon synthesis carried out
without increased pressure and at lower temperatures,
which was patented (D.R.P. 484337 and others) and given
the name Fischer-Tropsch synthesis. The history of the
discovery is described by Otto Roelen, one of the research
team involved at the time, in a paper presented and published in 1977 (Erdol, Kohle, Erdgas, Petrochem. 31 (1977)
Matthias W. Haenel [NB 876 IE]
Max-Planck-Institut fur Kohlenforschung,
Miilheirn a. d. Ruhr (FRG)
Multinuclear NMR. Edited by J . Mason. Plenum Press,
New York 1987. 639 pp., bound, $ 115.00.-ISBN 0-30642153-4
The publication of this book has been eagerly anticipated for some time in specialist circles, particularly in
view of the many new and important directions of research
which NMR spectroscopy has helped to stimulate in
nearly every area of chemistry and in interdisciplinary
fields. The 23 chapters of the book have been written by
twelve authors, and the editor is herself a co-author in five
of the chapters.
An explanation of the arrangement of the book’s contents and the scope of the different topics treated (Chapter
1) is followed by a concise account of the fundamentals of
the various NMR parameters (Chapter 2). Chapters 3-5
contain detailed discussions in turn of the chemical shift
(6),spin-spin coupling constants (“J), and relaxation processes. Chapters 1-5 take up about a quarter of the book.
Much of what they contain is, necessarily, familiar ground,
but they also bring out many aspects, especially concerning 6 and J, which could otherwise only be discovered
more laboriously from theoretical treatments, and might
therefore remain unknown to the preparative chemist. As
the title indicates, the book then continues, from Chapter 6
onwards, by dealing with the NMR parameters for the different nuclides, starting with ‘H, ’H, and 3H, and continuing through to the magnetically active isotopes of Cu, Ag,
Au, Zn, Cd, and Hg (Chapter 21). The arrangement of the
subject matter follows the groups of the Periodic System.
Some important nuclides (e.g. ’H, ”B, I3C, I9F, 31P)are
only dealt with briefly, the main emphasis being on inorAngew. Chem. lnt. Ed. Engl. 27 (1988) No. 10
Без категории
Размер файла
294 Кб
report, series, applied, critical, new, chemistry, chemical, book, coal, edited, processes, vol, review
Пожаловаться на содержимое документа