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Gas Systems: Applications to Flotation Research
P o w d e r T e c h n o l o g y . 15 ( 1 9 7 6 ) 293 - 294 © Elsevier Sequoia S.A., Lausanne - - Printed in the Netherlands
293
Book Review
Advances in Interfacial Phenomena of Particulate/Solution/Gas Systems: Applications to Flotation Research
P. S o m a s u n d a r a n a n d R. B. Grieves (Eds.), American Institute o f Chemical Engineers, S y m p o s i u m Series 150, 71, 1975, pp. 191, AIChE members S7, n o n m e m b e r s $20. This recent addition to the AIChE Symposium Series maintains the high standards set b y i t s p r e d e c e s s o r s . I t is a n a u t h o r i t a t i v e s e r i e s of papers on the interracial phenomena concerned with flotation as a separation process, drawing attention to the fact that the technique has applications extending beyond ore beneficiation. Among the applications t o u c h e d u p o n are p r e c i p i t a t e d m e t a l i o n removal (currently being developed for alum floc r e m o v a l i n p o t a b l e w a t e r t r e a t m e n t ) , calcium sulphate removal from scrubbing liquors, and the use of high expansion foams to collect sub-micron particles. The 25 papers of this symposium follow an introductory review by Somasundaran and are mainly concerned with the effects of ion and collector adsorption on flotation, using adsorption data and spectroscopic techniques to characterise the nature of the interface. The papers show in general a consolidation and refinement of our present views concerning the interracial phenomena concerned rather than striking off in new directions. Lin and Metzer draw attention to the signific a n c e o f t h e gas p h a s e i n f l o t a t i o n w i t h a s t u d y o f t h e u s e o f h y d r o c a r b o n s as f l o t a t i o n gases, a n d T e r - M i n a s s i a n - S a r a g a p r o p o s e s a m o d e l i n w h i c h n o n - r e v e r s i b l e w e t t i n g is shown to depend only on the adsorption equilibrium at the solid-liquid interface. Among the specific systems considered are haematite/octyl hydroxamate (Raghavan and D. W. F u r s t e n a u ) , p H e f f e c t s o n a l u m i n a (Wakamatsu and Mukai), general discussion of pH effects (Dixit and Biswas), the use of amphoteric collectors (Gupta and Smith), the adsorption of n-alkylamines on calcite and phosphate oolites (Cases et al.), adsorbed
cobalt at the oxide-water interface (Tewari and Mclntyre), the characterisation of sulphide mineral surfaces by electron spectroscopy (Clifford et al.), the adsorption of zinc II a t t h e c i n n a b a r - w a t e r i n t e r f a c e , a n d t h e properties of naturally hydrophobic solid~ ( F i n k e l s t e i n e t a l . , A r b i t e r e t al_, m a d C h a n d e r e t al. ). T h e s y m p o s i u m k e e p s w i t h i n its t e r m s o f reference by not discussing mass transport a n d d y n a m i c w e t t i n g p h e n o m e n a s u c h as t h e hydrodynamic aspects of particle capture by bubbles and the effects of disjoining pressure and other wetting phenomena on flotation. Two exceptions to this are an analysis of the rheology of high expansion foams by M a h a l i n g a m e t al. a n d a d e t e r m i n a t i o n o f s u r face equilibria and mass transfer rates in a co-current flow bubble column by ValdesK r i e g et al. In summary, a useful collection of papers for the worker with a general knowledge of flotation who wishes to bring himself up to date on the interracial factors concerned, particularly those involving the adsorption behaviour of ions and collectors. R. J. A k e r s
SI Units in Chemical Engineering and Technology
By K. D. Chandrasekaran a n d D. ~V-enkateswarlu, Chemical Engineering E d u c a t i o n Centre, Indian Ins t i t u t e o f Technology, 1974; pp. 181 + bibliography and index, £ 2 . 0 0 .
T h i s is a u s e f u l s e l e c t i o n o f c o n v e r s i o n f a c tors and physical properties intended primarily for chemical engineers. The authors have also included a description of the SI system, together with tables giving appropriate SI units and commonly used symbols for the quantities. The conversion tables are well laid out in a l p h a b e t i c a l o r d e r . A n o t a b l e f e a t u r e is t h e space devoted to them, and the form of the
293
Book Review
Advances in Interfacial Phenomena of Particulate/Solution/Gas Systems: Applications to Flotation Research
P. S o m a s u n d a r a n a n d R. B. Grieves (Eds.), American Institute o f Chemical Engineers, S y m p o s i u m Series 150, 71, 1975, pp. 191, AIChE members S7, n o n m e m b e r s $20. This recent addition to the AIChE Symposium Series maintains the high standards set b y i t s p r e d e c e s s o r s . I t is a n a u t h o r i t a t i v e s e r i e s of papers on the interracial phenomena concerned with flotation as a separation process, drawing attention to the fact that the technique has applications extending beyond ore beneficiation. Among the applications t o u c h e d u p o n are p r e c i p i t a t e d m e t a l i o n removal (currently being developed for alum floc r e m o v a l i n p o t a b l e w a t e r t r e a t m e n t ) , calcium sulphate removal from scrubbing liquors, and the use of high expansion foams to collect sub-micron particles. The 25 papers of this symposium follow an introductory review by Somasundaran and are mainly concerned with the effects of ion and collector adsorption on flotation, using adsorption data and spectroscopic techniques to characterise the nature of the interface. The papers show in general a consolidation and refinement of our present views concerning the interracial phenomena concerned rather than striking off in new directions. Lin and Metzer draw attention to the signific a n c e o f t h e gas p h a s e i n f l o t a t i o n w i t h a s t u d y o f t h e u s e o f h y d r o c a r b o n s as f l o t a t i o n gases, a n d T e r - M i n a s s i a n - S a r a g a p r o p o s e s a m o d e l i n w h i c h n o n - r e v e r s i b l e w e t t i n g is shown to depend only on the adsorption equilibrium at the solid-liquid interface. Among the specific systems considered are haematite/octyl hydroxamate (Raghavan and D. W. F u r s t e n a u ) , p H e f f e c t s o n a l u m i n a (Wakamatsu and Mukai), general discussion of pH effects (Dixit and Biswas), the use of amphoteric collectors (Gupta and Smith), the adsorption of n-alkylamines on calcite and phosphate oolites (Cases et al.), adsorbed
cobalt at the oxide-water interface (Tewari and Mclntyre), the characterisation of sulphide mineral surfaces by electron spectroscopy (Clifford et al.), the adsorption of zinc II a t t h e c i n n a b a r - w a t e r i n t e r f a c e , a n d t h e properties of naturally hydrophobic solid~ ( F i n k e l s t e i n e t a l . , A r b i t e r e t al_, m a d C h a n d e r e t al. ). T h e s y m p o s i u m k e e p s w i t h i n its t e r m s o f reference by not discussing mass transport a n d d y n a m i c w e t t i n g p h e n o m e n a s u c h as t h e hydrodynamic aspects of particle capture by bubbles and the effects of disjoining pressure and other wetting phenomena on flotation. Two exceptions to this are an analysis of the rheology of high expansion foams by M a h a l i n g a m e t al. a n d a d e t e r m i n a t i o n o f s u r face equilibria and mass transfer rates in a co-current flow bubble column by ValdesK r i e g et al. In summary, a useful collection of papers for the worker with a general knowledge of flotation who wishes to bring himself up to date on the interracial factors concerned, particularly those involving the adsorption behaviour of ions and collectors. R. J. A k e r s
SI Units in Chemical Engineering and Technology
By K. D. Chandrasekaran a n d D. ~V-enkateswarlu, Chemical Engineering E d u c a t i o n Centre, Indian Ins t i t u t e o f Technology, 1974; pp. 181 + bibliography and index, £ 2 . 0 0 .
T h i s is a u s e f u l s e l e c t i o n o f c o n v e r s i o n f a c tors and physical properties intended primarily for chemical engineers. The authors have also included a description of the SI system, together with tables giving appropriate SI units and commonly used symbols for the quantities. The conversion tables are well laid out in a l p h a b e t i c a l o r d e r . A n o t a b l e f e a t u r e is t h e space devoted to them, and the form of the