Gases In Molten Salts

This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

An element of obvious importance, mercury is also hazardous in the environment and corrosive to many materials. A knowledge of its solubility is inestimable in addressing problems concerning the element's concentration in our surroundings. This volume presents all relevant data published on the solubility of mercury up to June 1986. By combining these data with the mercury equilibrium vapour pressure, Henry's constant and Ostwald coefficients can be calculated.

The first chapter of this volume deals with computer simulation of molten salt behavior by molecular dynamics calculations. The next four chapters are reviews of experimental work: Chapter 2 deals with the solubility of nonre- active gases in molten salts, Chapter 3 with various types of organic reactions in molten tetrachloroaluminates, Chapter 4 with techniques for the study of molten fluorides, and Chapter 5 with the physical and chemical properties of thiocyanate melts. The last chapter is a collection of phase diagrams for binary and ternary fluoride systems. J. B., G. M., G. P. S. v CONTENTS Chapter 1 MOLECULAR DYNAMICS CALCULATIONS ON MOLTEN IONIC SALTS L. V. Woodcock 1. Introduction. . 4 2. Intermolecular Forces in Molten Salts 4 2.1. True and Effective Pair Potentials 2.2. Semiempirical Models 6 3. Computational Techniques 13 3.1. Molecular Dynamics Simulation 13 3.2. The Monte Carlo Method 15 3.3. Electrostatic Summations . . 18 4. Calculation of Physical Properties 23 4.1. Equilibrium Properties . 23 4.2. Transport Coefficients 27 4.3. Spectroscopic Properties 32 5. Applications...35 5.1. Studies of Interionic Forces. 35 5.2. Microstructure and Mechanisms 40 5.3.Interpretation of Experimental Observables 50 5.4. Reappraisal of Molten Salt Theories . 64 70 6. Conclusions 7. References. 72 vii Contents viii Chapter 2 GAS SOLUBILITY IN MOLTEN SALTS P. Field 1. Introduction 75 2. Experimental Techniques 78 3. Solution Thermodynamics.

This second volume carries on the excellent work of its predecessor, ex tending its scope to other melts and to other techniques. It continues to present first-hand understanding and experience of this difficult and demanding field. There is ever present the trade-off or reconciliation between the novel chemistry of systems not dominated by the mediating influence of a supposedly indifferent solvent and the high temperatures required to effect the fluidity of the system. At the limit, the very high temperatures so increase the rates of all reactions as to dissolve the temporal difference between the thermodynamic and the kinetic view of chemistry. What can happen will happen and invariably does happen. Vessels corrode, the apparatus becomes a reactant, and the number of tolerant materials able to withstand the attack shrinks to graphite, boron carbide or, if all else fails, to frozen parts of the molten salt itself. It is probably true that there is no limit to man's ingenuity but I believe that God gave us molten salts just to test that thesis. If there is ever a Molten Salt Club, and Englishmen love clubs, its membership will be exclusive. It would certainly include the authors of this series. Graham Hills University of Strathclyde ix Preface In the first volume of this series, we expressed our contention that a real need existed for practical guidance in the field of molten salt experimentation.

Molten salts and fused media provide the key properties and the theory of molten salts, as well as aspects of fused salts chemistry, helping you generate new ideas and applications for fused salts. Molten Salts Chemistry: From Lab to Applications examines how the electrical and thermal properties of molten salts, and generally low vapour pressure are well adapted to high temperature chemistry, enabling fast reaction rates. It also explains how their ability to dissolve many inorganic compounds such as oxides, nitrides, carbides and other salts make molten salts ideal as solvents in electrometallurgy, metal coating, treatment of by-products and energy conversion. This book also reviews newer applications of molten salts including materials for energy storage such as carbon nano-particles for efficient super capacitors, high capacity molten salt batteries and for heat transport and storage in solar plants. In addition, owing to their high thermal stability, they are considered as ideal candidates for the development of safer nuclear reactors and for the treatment of nuclear waste, especially to separate actinides from lanthanides by electrorefining. Explains the theory and properties of molten salts to help scientists understand these unique liquids Provides an ideal introduction to this expanding field Illustrated text with key real-life applications of molten salts in synthesis, energy, nuclear, and metal extraction