Extraction, emerging developments

Timothy C. Frank, Ph.D. Research Scientist and Sr. Technical Leader, The Dow Chemical Company Member, American Institute of Chemical Engineers (Section Editor, Introduction and Overview, Thermodynamic Basis for Liquid-Liquid Extraction, Solvent Screening Methods, Liquid-Liquid Diversion Fundamentals, Process Fundamentals and Basic Calculation Methods, Dual-Solvent Fractional Extraction, Extractor Selection, Packed Columns, Agitated Extraction Columns, Mixer-Settler Equipment, Centrifugal Extractors, Process Control Considerations, Liquid-Liquid Phase Separation Equipment, Emerging Developments)... 

T. K. Mukherjee and C. K. Gupta, Flowsheets Development for Recovery of Nonferrous Metal values from Secondary Resources by Solvent Extraction, Proceed, of a Symposium - Emerging Separation Technologies for Metals II Sponsored by the Engineers Foundation Conference and the National Science Foundation held at Kona, Hawaii, June 16-21,1996. 

It is of interest to examine the development of the analytical toolbox for rubber deformulation over the last two decades and the role of emerging technologies (Table 2.9). Bayer technology (1981) for the qualitative and quantitative analysis of rubbers and elastomers consisted of a multitechnique approach comprising extraction (Soxhlet, DIN 53 553), wet chemistry (colour reactions, photometry), electrochemistry (polarography, conductometry), various forms of chromatography (PC, GC, off-line PyGC, TLC), spectroscopy (UV, IR, off-line PylR), and microscopy (OM, SEM, TEM, fluorescence) [10]. Reported applications concerned the identification of plasticisers, fatty acids, stabilisers, antioxidants, vulcanisation accelerators, free/total/bound sulfur, minerals and CB. Monsanto (1983) used direct-probe MS for in situ quantitative analysis of additives and rubber and made use of 31P NMR [69]. 

Imperial Smelting A process for simultaneously extracting zinc and lead from sulfide ores, developed and commercialized by the Imperial Smelting Corporation at Avonmouth, UK, after World War II, and now widely used. Based on an invention by L. J. Derham in which the vapors emerging from a reducing kiln are rapidly quenched in a shower of droplets of molten lead. The first trial was made in 1943 but most of the development work was done from 1945 to 1947. Eleven plants were operating in 1973. 

A major emerging area of research activity in interfacial electrochemistry concerns the development of in-situ surface spectroscopic methods, especially those applicable in conventional electrochemical circumstances. One central objective is to obtain detailed molecular structural information for species within the double layer to complement the inherently macroscopic information that is extracted from conventional electrochemical techniques. Vibrational spectroscopic methods are particularly valuable for this purpose in view of their sensitivity to the nature of intermolecular interactions and surface bonding as well as to molecular structure. Two such techniques have been demonstrated to be useful in electrochemical systems surface-enhanced Raman spectroscopy... 

Soybeans have been used as food in the Orient since ancient times and various methods have been developed to make soybeans as palatable as possible. In recent years, a large number of these simply processed soyfoods are emerging in the West. Tofu and tempeh are the most popular and have the fastest growth rate of any soyfood in America. Tofu is made by coagulating the protein with a calcium or magnesium salt from a hot-water extracted, protein-oil emulsion of whole soybeans. 

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