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NMR of Humic Substances and Coal: Techniques, Problems and Solutions
72
BOOK REVIEWS:J.K. HARDIE/E. KAINKA-STANICKE
near nationwide applications, having little regard for economic, topographic, climatic, and geologic variations in different geographic regions. The theme often repeated in the text goes beyond considering only these regional variations and treats reclamation on a site specific basis, with each mine site having a family of common and unique problems requiring tailored procedural remedies. It was apparent after reading this book that successful reclamation must allow for the modification and adaptation of field test procedures, such as those presented in this text. With some regularity throughout much of the book, the need for greater flexibility in reclamation legislation was repeated, Immediately following the 1977 legislation, it was sufficient that regulatory agencies mandated specific reclamation criteria having clear measurable results, because there were comparatively few field tested reclamation options that operators could adapt to their needs. The legislation produced fairly rigid criteria that were simple for state and federal regulatory agencies to monitor and regulate but the criteria have become dated. For example, the mandate to restore post-mined lands to pre-mined topography and land use is not always the best approach, both environmentally and economically. Instead, flexibility in regulations allowing for alternative land use such as wetlands development, would provide wildlife habitat to help replace the destruction of wetlands. Innovations such as that would significant reduce the operators reclamation costs by reducing soil handling and reconstruction, a major expense in reestablishing pre-mining topography and soil productivity. I found it inappropriate and distracting that the author of a paper included in the book was allowed to "plug" a reclamation-oriented product marketed by a company that he manages. In summation, this rather attractively bound book is interesting and will be of great use to those actively involved with reclamation problems ..... the $50.00 cost is money well spent. J.K. H A R D I E (Denver, Colo. )
NMR of Humic Substances and Coal: Techniques, Problems and Solutions, edited by R.L. Wershaw and A. Mikita. Lewis Publishers, Chelsea, 1987, xvii + 236 pp., Price: Lst. 41.05. Hardback. In the last thirty years, nuclear magnetic resonance spectroscopy has become an indispensable instrument of organic chemistry that can be used in a many-sided manner to elucidate chemical and stereochemical problems. In the last ten years, the technique of NMR spectroscopy, and especially the C-13 NMR spectroscopy, has become an established method for analysis of humic
BOOK REVIEW: E. KAINKA-STANICKE/A.D.WALTERS
73
substances and coal. It can be stated that, of the relatively few solid-state analytical techniques which have been applied to solid humic substances and coal, NMR is the one which appears to have found the widest use. But nevertheless too much must not be expected from this technique. Because it is not yet standardized - spectrometer conditions and calculation methods vary intensively - and is affected with errors, at the present stage of development it would probably be best to treat extensively processed NMR data with suspicion, especially if the results are applied to individual samples, for example in the case of the multi-component mixture coals. The most important sources of errors, besides the known insufficiencies of the apparatus, may probably be the complexity and heterogeneity of the feedstock. This may present some of the problems and special difficulties that adhere to a book like this one. It is not a textbook for students but it is a symposium volume which is directed primarily to the working scientist but also to other interested persons. The reader gets a many-sided and intensive insight into the present stage of a still non-uniform method and the interpretation of NMR techniques for humic substances and coal. In this sense, the review character of some chapters and their large bibliography are of much value, making it possible to intensify our knowledge of this topic. Up to now, this one has been the only symposium resulting in a book that deals with the NMR spectroscopy of humic substances and coal. The authors extend to present an introduction, which seems to be rather short here, and guidance in the application of NMR spectroscopy to the study of the chemical structure of humic substances and coal. Indeed, it provides a more or less coherent representation of problems with which the working scientist is confrontet and suggests possible solutions to these problems, though many questions must remain unanswered, as is to be expected. I fed that NMR spectroscopy of coal is not sufficiently covered in this book. Distinctly more emphasis is laid on NMR spectroscopy of humic substances. But worldwide there exists an especially wide interest in coal, and in the results and interpretation of NMR spectroscopy. The editors, R.L. Wershaw (Denver), a geochemist, and M.A. Mikita (Denver ), a chemist, are members of the International Humic Substances Society Communications and eminent scientists in this field. The authors of the particular chapters, likewise experts in their respective fields, are American scientists nearly without exception. The book under consideration is a hard-back. It is conspicuous that the type face changes from chapter to chapter. The figures, mostly representations of spectra, are in general readable, but sometimes so much reduced that the letters melt into one another. The chapters themself are homogeneous, even when there are more authors,
74
BOOKREVIEWS:J.K. HARDIE/E.KAINKA.STANICKE
but differ among each other greatly with regard to the kind of representation, scope, weighing of a theme, theory, reference to praxis, bibliography, etc. Chapters 1-4 provide, partly in the form of reviews, a general discussion of the application of liquid-state and solid-state NMR to humic substances and coal, in the course of which a whole chapter deals with the theme of electric paramagnetic resonance (ESR) spectroscopy. Unfortunately, I miss a similar group of chapters on coal. Instead of this the editors refer to a book by D.E. Axelson (Canada) which provides a profound consideration of this theme. Chapters 5 and 6 deal with a general discussion of the application of twodimensioned N M R techniques for treated humic acid and Illinois coal such as polarisation transfer and selective derivatization. Chapter 7 presents the state of development of the techniques of wideline N M R spectroscopy. The effects of molecular mobility on the solid-state N M R spectra of humic substances and coal are dealt with in chapters 8 and 9. In both of these materials, NMR evidence for relatively mobile zones in apparently solid material has been found. The nature of these zones has not yet been completely cleared up. Chapter 8 ( D.E. Axelson ) seems to be of the most interest to coal scientists. It provides, for example, NMR spectra (C-13 CP MAS) of macerals of subbituminous B Alberta coals and studies of carbon aromaticity fa as a measure of the number of carbons in aromatic ring structures. But here I miss a summary of the representation of such important investigations and a discussion of the results. Chapter 10 deals with an interesting discussion of the NMR evidence for a membrane model of soil humic acid, while Chapter 11 provides a resume of solid-state NMR with an intensive examination of factors affecting reliable interpretation and valueable suggestions for future work. In the last chapter the editors try to give a general resume. They add some good, and, I think, important complements on the NMR spectroscopy of coal. Although the explained aim of this symposium volume could only be conditionally attained, I am absolutely convinced that the book is of great value to the working scientist and of interest to motivated readers. EVA KAINKA-STJ/,NICKE (Heiligenhaus, FRG)
Fine Coal Processing, edited by Surendra K. Mishra and Richard R. Klimpel. Noyes Publications, New Jersey, 1987, 452 pp., US$ 48.00. (hardback). With the desulphurization of coal becoming an increasingly urgent issue, this volume is particularly timely. It may well be that in the future large-scale crushing of high-sulphur thermal coals will be necessary for liberation pur-
BOOK REVIEWS:J.K. HARDIE/E. KAINKA-STANICKE
near nationwide applications, having little regard for economic, topographic, climatic, and geologic variations in different geographic regions. The theme often repeated in the text goes beyond considering only these regional variations and treats reclamation on a site specific basis, with each mine site having a family of common and unique problems requiring tailored procedural remedies. It was apparent after reading this book that successful reclamation must allow for the modification and adaptation of field test procedures, such as those presented in this text. With some regularity throughout much of the book, the need for greater flexibility in reclamation legislation was repeated, Immediately following the 1977 legislation, it was sufficient that regulatory agencies mandated specific reclamation criteria having clear measurable results, because there were comparatively few field tested reclamation options that operators could adapt to their needs. The legislation produced fairly rigid criteria that were simple for state and federal regulatory agencies to monitor and regulate but the criteria have become dated. For example, the mandate to restore post-mined lands to pre-mined topography and land use is not always the best approach, both environmentally and economically. Instead, flexibility in regulations allowing for alternative land use such as wetlands development, would provide wildlife habitat to help replace the destruction of wetlands. Innovations such as that would significant reduce the operators reclamation costs by reducing soil handling and reconstruction, a major expense in reestablishing pre-mining topography and soil productivity. I found it inappropriate and distracting that the author of a paper included in the book was allowed to "plug" a reclamation-oriented product marketed by a company that he manages. In summation, this rather attractively bound book is interesting and will be of great use to those actively involved with reclamation problems ..... the $50.00 cost is money well spent. J.K. H A R D I E (Denver, Colo. )
NMR of Humic Substances and Coal: Techniques, Problems and Solutions, edited by R.L. Wershaw and A. Mikita. Lewis Publishers, Chelsea, 1987, xvii + 236 pp., Price: Lst. 41.05. Hardback. In the last thirty years, nuclear magnetic resonance spectroscopy has become an indispensable instrument of organic chemistry that can be used in a many-sided manner to elucidate chemical and stereochemical problems. In the last ten years, the technique of NMR spectroscopy, and especially the C-13 NMR spectroscopy, has become an established method for analysis of humic
BOOK REVIEW: E. KAINKA-STANICKE/A.D.WALTERS
73
substances and coal. It can be stated that, of the relatively few solid-state analytical techniques which have been applied to solid humic substances and coal, NMR is the one which appears to have found the widest use. But nevertheless too much must not be expected from this technique. Because it is not yet standardized - spectrometer conditions and calculation methods vary intensively - and is affected with errors, at the present stage of development it would probably be best to treat extensively processed NMR data with suspicion, especially if the results are applied to individual samples, for example in the case of the multi-component mixture coals. The most important sources of errors, besides the known insufficiencies of the apparatus, may probably be the complexity and heterogeneity of the feedstock. This may present some of the problems and special difficulties that adhere to a book like this one. It is not a textbook for students but it is a symposium volume which is directed primarily to the working scientist but also to other interested persons. The reader gets a many-sided and intensive insight into the present stage of a still non-uniform method and the interpretation of NMR techniques for humic substances and coal. In this sense, the review character of some chapters and their large bibliography are of much value, making it possible to intensify our knowledge of this topic. Up to now, this one has been the only symposium resulting in a book that deals with the NMR spectroscopy of humic substances and coal. The authors extend to present an introduction, which seems to be rather short here, and guidance in the application of NMR spectroscopy to the study of the chemical structure of humic substances and coal. Indeed, it provides a more or less coherent representation of problems with which the working scientist is confrontet and suggests possible solutions to these problems, though many questions must remain unanswered, as is to be expected. I fed that NMR spectroscopy of coal is not sufficiently covered in this book. Distinctly more emphasis is laid on NMR spectroscopy of humic substances. But worldwide there exists an especially wide interest in coal, and in the results and interpretation of NMR spectroscopy. The editors, R.L. Wershaw (Denver), a geochemist, and M.A. Mikita (Denver ), a chemist, are members of the International Humic Substances Society Communications and eminent scientists in this field. The authors of the particular chapters, likewise experts in their respective fields, are American scientists nearly without exception. The book under consideration is a hard-back. It is conspicuous that the type face changes from chapter to chapter. The figures, mostly representations of spectra, are in general readable, but sometimes so much reduced that the letters melt into one another. The chapters themself are homogeneous, even when there are more authors,
74
BOOKREVIEWS:J.K. HARDIE/E.KAINKA.STANICKE
but differ among each other greatly with regard to the kind of representation, scope, weighing of a theme, theory, reference to praxis, bibliography, etc. Chapters 1-4 provide, partly in the form of reviews, a general discussion of the application of liquid-state and solid-state NMR to humic substances and coal, in the course of which a whole chapter deals with the theme of electric paramagnetic resonance (ESR) spectroscopy. Unfortunately, I miss a similar group of chapters on coal. Instead of this the editors refer to a book by D.E. Axelson (Canada) which provides a profound consideration of this theme. Chapters 5 and 6 deal with a general discussion of the application of twodimensioned N M R techniques for treated humic acid and Illinois coal such as polarisation transfer and selective derivatization. Chapter 7 presents the state of development of the techniques of wideline N M R spectroscopy. The effects of molecular mobility on the solid-state N M R spectra of humic substances and coal are dealt with in chapters 8 and 9. In both of these materials, NMR evidence for relatively mobile zones in apparently solid material has been found. The nature of these zones has not yet been completely cleared up. Chapter 8 ( D.E. Axelson ) seems to be of the most interest to coal scientists. It provides, for example, NMR spectra (C-13 CP MAS) of macerals of subbituminous B Alberta coals and studies of carbon aromaticity fa as a measure of the number of carbons in aromatic ring structures. But here I miss a summary of the representation of such important investigations and a discussion of the results. Chapter 10 deals with an interesting discussion of the NMR evidence for a membrane model of soil humic acid, while Chapter 11 provides a resume of solid-state NMR with an intensive examination of factors affecting reliable interpretation and valueable suggestions for future work. In the last chapter the editors try to give a general resume. They add some good, and, I think, important complements on the NMR spectroscopy of coal. Although the explained aim of this symposium volume could only be conditionally attained, I am absolutely convinced that the book is of great value to the working scientist and of interest to motivated readers. EVA KAINKA-STJ/,NICKE (Heiligenhaus, FRG)
Fine Coal Processing, edited by Surendra K. Mishra and Richard R. Klimpel. Noyes Publications, New Jersey, 1987, 452 pp., US$ 48.00. (hardback). With the desulphurization of coal becoming an increasingly urgent issue, this volume is particularly timely. It may well be that in the future large-scale crushing of high-sulphur thermal coals will be necessary for liberation pur-