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Hydrometallurgy
Minerals Engineering, Vol. 11, No. 8, pp. 789-790, 1998
Pergamon 0892-6875(98)00063-6
© 1998ElsevierScienceLtd All rightsreserved 0892-6875/98/5- see frontmatter
BOOK REVIEW
Hydrometallurgy S. Venkatachalam Narosa Publishing House, New Delhi, 1998. 318 pps. Price £27.50. ISBN 81-7319-116-6
Hydrometallurgy is advancing very rapidly. This is the second book devoted to this subject by Indian authors; the first being by C.K. Gupta and T.K. Mukherjee published in 1990. In the introductory chapter the author outlines the different areas of extractive metallurgy and the composition of the Earth's crust. However, in Figure 1.1 the author gives a distorted flowsheet for a "Generalized hydrometallurgical flow diagram". After regenerating the leaching agent he "bleeds" a part and then uses the other part for "solid wash". It is not clear why he bleeds a regenerated reagent? This cannot be taken seriously. Further, nowhere there is mention of purification of the leach solution. The author then goes on to Chapter two entitled "Pretreatment methods--Roasting". Here he introduces "chloridizing roast" and "carburizing roast". In the first a metal sulfide or oxide is treated with a chloride or chlorine, while in the second, chlorine and carbon are used. Evidently, this terminology is unacceptable since both processes are chlorination reactions. In Chapter 3 entitled "Leaching", the author spends much effort under a heading "principles of Leaching" discussing the systems Zn-H20, Cu-H20, Au-H20, then goes on without any heading to discuss effect of complexing agents and other complex systems as Cu-Fe-S-H20. Under "Kinetics of Leaching" the author relies mainly on old work published in 1957. On page 43 he cites erroneously the Bayer process as leaching of AI203, and not AI(OH)3, in NaOH. Chapter 4 entitled "Pressure Leaching" has a main heading "Thermodynamics" and as sub-headings one finds "Kinetics and Autoclaves" ! ! Chapter 5 entitled "Microbial Leaching" is followed by Chapter 6 "Electrochemical Processes in Leaching" which is based mainly on work published by M.E. Wadsworth in 1970 and 1980's. The next two chapters are entitled "Ion Exchange" and "Solvent Extraction". Here, the reader is confronted for the first time with these topics, nothing was mentioned before why these processes are used. Strangely enough, "Adsorption Using Activated Charcoal" is treated under the heading "Separation of Rare Earths by Ion Exchange" ! (page 143). In the last two chapters, entitled "Metal Recovery from Leach solutions" and "Electrolytic Processes", respectively, the reader finds typical precipitation processes, the electrowinning, and the electrorefining processes. The last two operations are usually found in electrometallurgy and electrochemistry books. Finally, the book ends with five appendices on computer programs and a Table of standard free energies (51 pages). The book is a compilation of numerous Figures taken from the literature with much repetition and no synthesis. The author is certainly unaware of the reviewer's "Textbook of Hydrometallurgy" published in 789
790
Book Review
1993 in 700 pages, and he relied heavily on old references. The reviewer is not in a position to give judgement on the five appendices dealing with computer programs, but certainly, he does not recommend the book for students or engineers.
Fathi Habashi Universit~ Laval, Quebec City Canada
Pergamon 0892-6875(98)00063-6
© 1998ElsevierScienceLtd All rightsreserved 0892-6875/98/5- see frontmatter
BOOK REVIEW
Hydrometallurgy S. Venkatachalam Narosa Publishing House, New Delhi, 1998. 318 pps. Price £27.50. ISBN 81-7319-116-6
Hydrometallurgy is advancing very rapidly. This is the second book devoted to this subject by Indian authors; the first being by C.K. Gupta and T.K. Mukherjee published in 1990. In the introductory chapter the author outlines the different areas of extractive metallurgy and the composition of the Earth's crust. However, in Figure 1.1 the author gives a distorted flowsheet for a "Generalized hydrometallurgical flow diagram". After regenerating the leaching agent he "bleeds" a part and then uses the other part for "solid wash". It is not clear why he bleeds a regenerated reagent? This cannot be taken seriously. Further, nowhere there is mention of purification of the leach solution. The author then goes on to Chapter two entitled "Pretreatment methods--Roasting". Here he introduces "chloridizing roast" and "carburizing roast". In the first a metal sulfide or oxide is treated with a chloride or chlorine, while in the second, chlorine and carbon are used. Evidently, this terminology is unacceptable since both processes are chlorination reactions. In Chapter 3 entitled "Leaching", the author spends much effort under a heading "principles of Leaching" discussing the systems Zn-H20, Cu-H20, Au-H20, then goes on without any heading to discuss effect of complexing agents and other complex systems as Cu-Fe-S-H20. Under "Kinetics of Leaching" the author relies mainly on old work published in 1957. On page 43 he cites erroneously the Bayer process as leaching of AI203, and not AI(OH)3, in NaOH. Chapter 4 entitled "Pressure Leaching" has a main heading "Thermodynamics" and as sub-headings one finds "Kinetics and Autoclaves" ! ! Chapter 5 entitled "Microbial Leaching" is followed by Chapter 6 "Electrochemical Processes in Leaching" which is based mainly on work published by M.E. Wadsworth in 1970 and 1980's. The next two chapters are entitled "Ion Exchange" and "Solvent Extraction". Here, the reader is confronted for the first time with these topics, nothing was mentioned before why these processes are used. Strangely enough, "Adsorption Using Activated Charcoal" is treated under the heading "Separation of Rare Earths by Ion Exchange" ! (page 143). In the last two chapters, entitled "Metal Recovery from Leach solutions" and "Electrolytic Processes", respectively, the reader finds typical precipitation processes, the electrowinning, and the electrorefining processes. The last two operations are usually found in electrometallurgy and electrochemistry books. Finally, the book ends with five appendices on computer programs and a Table of standard free energies (51 pages). The book is a compilation of numerous Figures taken from the literature with much repetition and no synthesis. The author is certainly unaware of the reviewer's "Textbook of Hydrometallurgy" published in 789
790
Book Review
1993 in 700 pages, and he relied heavily on old references. The reviewer is not in a position to give judgement on the five appendices dealing with computer programs, but certainly, he does not recommend the book for students or engineers.
Fathi Habashi Universit~ Laval, Quebec City Canada