Electrochemistry in Nonaqueous Solutions


Book Description

An excellent resource for all graduate students and researchers using electrochemical techniques. After introducing the reader to the fundamentals, the book focuses on the latest developments in the techniques and applications in this field. This second edition contains new material on environmentally-friendly solvents, such as room-temperature ionic liquids.




Physical Chemistry of Organic Solvent Systems


Book Description

We believe this to be the first monograph devoted to the physicochemical properties of solutions in organic solvent systems. Although there have 1 been a number of books on the subject of non-aqueous solvents - 4, they have been devoted, almost entirely, to inorganic solvents such as liquid ammonia, liquid sulphur dioxide, etc. A variety of new solvents such as dimethylformamide, dimethylsulphoxide and propylene carbonate have become commercially available over the last twenty years. Solutions in these solvents are of technological interest in connection with novel battery systems and chemical synthesis, while studies of ion solvation and transport properties have fostered academic interest. This monograph is primarily concerned with electrolytic solutions although discussion of non-electrolyte solutions has not been excluded. We have deliberately omitted consideration of the important area of solvent extraction, since this has been adequately covered elsewhere. Our contributors were asked to review and discuss their respective areas with particular reference to differences in technique necessitated by use of non-aqueous solvents while not reiterating facts well-known from experience with aqueous solutions. We have striven to build their contributions into a coherent and consistent whole. We thank our con tributors for following our suggestions so ably and for their forebearance in the face of our editorial impositions.




Non-aqueous Solvent Systems


Book Description




The Chemistry of Nonaqueous Solvents V4


Book Description

The Chemistry of Nonaqueous Solvents, Volume IV: Solution Phenomena and Aprotic Solvents focuses on the chemistry of nonaqueous solvents, with emphasis on solution phenomena and aprotic solvents such as tetramethylurea, inorganic acid chlorides, cyclic carbonates, and sulfolane. This book is organized into seven chapters and begins with an overview of the theory of electrical conductivity and elementary experimental considerations, along with some of the interesting research on nonaqueous solvents. It then turns to a discussion on hydrogen bonding phenomena in nonaqueous systems as probed by four spectroscopic techniques; the different methods used in studying redox systems in nonaqueous solvents such as potentiometry and steady state diffusion methods; and the use of tetramethylurea as a nonaqueous medium for chemical reactions and chemical investigations. The reader is also introduced to inorganic acid chlorides of high dielectric constant, with special reference to antimony trichloride, and preparation methods for cyclic carbonates including vinylene carbonate, ethylene carbonate, propylene carbonate, and butylene carbonate. The book concludes with a chapter on sulfolane, focusing on its preparation and purification, physical properties, and toxicology. This book will be of interest to chemists who want to know more about nonaqueous solvents.




Ph Measurements


Book Description

pH Measurements is a seven-chapter simplified text on obtaining a high degree of accuracy in practical pH measurement. The introductory chapter of this book relates the principles of pH measurements to the actual measurement. This chapter specifically tackles the factors involved in the measurement and what magnitude of effect does each factor have on the measurement. These topics are followed by discussions on the components of pH equipment and technique, including the electrodes and buffers. A chapter considers the general approach of pH measurements and illustrates with examples of some common difficult samples. The concluding chapter shows the isolation and correction a pH equipment malfunction. pH equipment operators and users will find this book rewarding.




Enzymes in Nonaqueous Solvents


Book Description

Enzymatic catalysis has gained considerable attention in recent years as an efficient tool in the preparation of natural products, pharmaceuticals, fine chemicals, and food ingredients. The high selectivity and mild reaction con- tions associated with enzymatic transformations have made this approach an attractive alternative in the synthesis of complex bioactive compounds, which are often difficult to obtain by standard chemical routes. However, the maj- ity of organic compounds are not very soluble in water, which was traditi- ally perceived as the only suitable reaction medium for the application of biocatalysts. The realization that most enzymes can function perfectly well under nearly anhydrous conditions and, in addition, display a number of useful properties, e. g. , highly enhanced stability and different selectivity, has d- matically widened the scope of their application to the organic synthesis. Another great attraction of using organic solvents rather than water as a reaction solvent is the ability to perform synthetic transformations with re- tively inexpensive hydrolytic enzymes. It is worth reminding the reader that in vivo, the synthetic and hydrolytic pathways are catalyzed by different enzymes. However, elimination of water from the reaction mixture enables the “reversal” of hydrolytic enzymes and thus avoids the use of the expensive cofactors or activated substrates that are required for their synthetic count- parts.




Buffers for pH and Metal Ion Control


Book Description

This book is intended as a practical manual for chemists, biologists and others whose work requires the use of pH or metal-ion buffers. Much information on buffers is scattered throughout the literature and it has been our endeavour to select data and instructions likely to be helpful in the choice of suitable buffer substances and for the preparation of appropriate solutions. For details of pH measurement and the preparation of standard acid and alkali solutions the reader is referred to a companion volume, A. Albert and E. P. Serjeant's The Determination of Ionization Constants (1971). Although the aims of the book are essentially practical, it also deals in some detail with those theoretical aspects considered most helpful to an understanding of buffer applications. We have cast our net widely to include pH buffers for particular purposes and for measurements in non-aqueous and mixed solvent systems. In recent years there has been a significant expansion in the range of available buffers, particularly for biological studies, largely in conse quence of the development of many zwiUerionic buffers by Good et al. (1966). These are described in Chapter 3.




The Chemistry of Nonaqueous Solvents III


Book Description

The Chemistry of Nonaqueous Solvents, Volume III: Inert, Aprotic, and Acidic Solvents is a compilation of critical surveys of specific solvent systems. The compendium contains discussions on the solution chemistry of sulfur dioxide and acyl halides; the solvent properties of hydrogen sulfide and carboxylic acids; and the Bronsted acid-base behavior in inert organic solvents. Chemists, researchers, and students of chemistry and chemical engineering will find the book a good reference material.




Solvent Systems and Their Selection in Pharmaceutics and Biopharmaceutics


Book Description

Solvent systems are integral to drug development and pharmaceutical technology. This single topic encompasses numerous allied subjects running the gamut from recrystallization solvents to biorelevant media. The goal of this contribution to the AAPS Biotechnology: Pharmaceutical Aspects series is to generate both a practical handbook as well as a reference allowing the reader to make effective decisions concerning the use of solvents and solvent systems. To this end, the monograph was created by inviting recognized experts from a number of fields to author relevant sections. Specifically, 15 chapters have been designed covering the theoretical background of solubility, the effect of ionic equilibria and pH on solubilization, the use of solvents to effect drug substance crystallization and polymorph selection, the use of solvent systems in high throughput screening and early discovery, solvent use in preformulation, the use of solvents in bio-relevant dissolution and permeation experiments, solvents and their use as toxicology vehicles, solubilizing media and excipients in oral and parenteral formulation development, specialized vehicles for protein formulation and solvent systems for topical and pulmonary drug administration. The chapters are organized such that useful decision trees are included together with the scientific underpinning for their application. In addition, trends in the use of solvent systems and a balance of current views make this monograph useful to both the novice and experienced researcher and to scientists at all developmental stages from early discovery to late pharmaceutical operations.