Conventional methods for extraction of the active constituents from herbal plants, in addition to their high processing costs, are harmful to the environment owing to their time and energy consumption, uncontrollable parameters, use of toxic and dangerous solvents, loss of the extract, thermal instability, the contamination of the product with organic solvents and the loss of water-soluble comp...

The structure and properties of supercritical water is investigated in relation to the energy and environmental issues of the 21 century. Molecular interpretations are given to the temperature dependence of the hydrogen-bonding structure, dynamics, and chemical reactions of supercritical water. The three-dimensional network structure, characteristic of ambient water, is broken down in hot expan...

Supercritical fluid extraction (SFE), which has received much interest in its use and further development for industrial applications, is a method that offers some advantages over conventional methods, especially for the palm oil industry. SC-CO₂ refers to supercritical fluid extraction (SFE) that uses carbon dioxide (CO₂) as a solvent which is a nontoxic, inexpensive, nonflammable, and nonpoll...

With high pressures, supercritical fluids can be studied over a very wide range of density. Fluids with strongly interacting polar molecules for example water are of particular interest. Results for several thermophysical properties are discussed. Density, dielectric constant and self—ionization of water have been determined or predicted to 1000 °C. Beyond 20 GPa very hot water appears to becom...

Palladium nanoparticles, simply and briefly generated in commercial and cheap onium salts using supercritical carbon dioxide, have been found to be an effective catalytic system for additive free N-alkylation reaction using alcohols via cascade oxidation/condensation/reduction steps.

Triterpene compounds like betulin, betulinic acid, erythrodiol, oleanolic acid and lupeol are known for many pharmacological effects. All these substances are found in the outer bark of birch. Apart from its pharmacological effects, birch bark extract can be used to stabilise semisolid systems. Normally, birch bark extract is produced for this purpose by extraction with organic solvents. Employ...

Supercritical carbon dioxide (scCO2) could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs). Unfortunately, carbon dioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of ca...

Knutson (Last Name) Brian (First Name) D. (Middle Initial) The Use of a Supercritical Carbon Dioxide-Based Solvent as a Cost Effective and (Title) Environmentally Sound Alternative to Current Photoresist Stripping Solvents M.S. in Risk Control Elbert Sorrell, Ph.D. 5/2002 25 (Graduate Major) (Research Advisor) (Month/Year) (Pages) American Psychological Association Style Manual (Name of Style M...

The seed lipid of Nitraria tangutorum was extracted by supercritical carbon dioxide extraction, microwaveassisted reflux extraction, ultrasound-assisted extraction, or solvent reflux extraction. The experimental parameters of supercritical carbon dioxide extraction including pressure, temperature, particle size, and extraction time were investigated. A facile and sensitive method for the simult...

Air-starved combustion of biomass and fossil fuels releases aerosols, including airborne carbonaceous particles, causing negative climatic and health effects. Radiocarbon analysis of the elemental carbon (EC) fraction can help apportion sources of its emission, which is greatly constrained by the challenges in isolation of EC from organic compounds in atmospheric aerosols. The isolation of EC u...