Extraction and separation processes

Another extraction and separation process is described in U.S. Patent 2,992,162. 

Many of the waste streams from U.S. process industries are water containing small quantities of metal ions that the law requires be removed before the wastewater is disposed of There is an economic incentive to recoup at least some of the cost of wastewater treatment by recovering and selling the metal content instead of merely disposing of the metals as sludge. Because the waste streams are dilute in desired materials, research is needed to devise efficient extraction and separation processes. 

Supercritical fluids also find application in the areas of pollution prevention and remediation, and supercritical carbon dioxide is used as a replacement solvent for many hazardous solvents in both extraction and separation processes and also as a reaction medium and in materials processing. Although carbon dioxide is considered as a greenhouse gas , there is actually no net increase in the amount of the gas if it is removed from the environment, used as the solvent instead of a hazardous substance, and returned to the environment. In this way, most of the uses of supercritical carbon dioxide may be considered as environmentally friendly. Because the solubilities of oils and greases in carbon dioxide are high, it is particularly suited to the cleaning of machinery 47 and, as discussed in the literature 48, it is used as a solvent in textile dyeing operations where it is used to treat any dye-laden... 

In the last years supercritical fluid (SCF) technology has occupied a significant place in the high pressure chemical engineering. Due to their specific properties as liquid-like densities, gas-like viscosities and diffusivities intermediate between gas and liquid values, SCF have large potential in extraction and separation processes, polymer science and technology and in elaboration of new materials [1-4], In these last cases, to control the size of particles, we have to deal with the kinetics of their formation. ... 

Distribution of a Single Species between Immiscible Phases Extraction and Separation Processes... 

Extraction and separation processes are basic industrial operations applied in many areas with considerable economic relevance. Supercritical fluids, especially carbon dioxide, are of increasing interest for new separation processes in the fields of foodstuffs, cosmetics and pharmaceuticals. 

Extraction and separation processes using chemomechanical systems... 

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