The invention discloses a method for producing bio-fuel (BF) from a high-viscosity biomass using thermo-chemical conversion of the biomass in a production line (10) with pumping means (PM), heating means (HM) and cooling means (CM). The method has the steps of 1) operating the pumping means, the heating means and the cooling means so that the production line is under supercritical fluid conditions (SCF) to induce biomass conversion in a conversion zone (CZ) within the production line, and 2) operating the pumping means so that at least part of the production line is in an oscillatory flow (OF) mode. The invention is advantageous for providing an improved method for producing biofuel from a high-viscosity biomass. This is performed by an advantageous combination of two operating modes: supercritical fluid (SCF) conditions and oscillatory flow (OF).

Described herein are methods, systems, and techniques relating to clathrate hydrate formation processes and, particularly, involving reactive metal nucleation substrates for promoting clathrate hydrate formation. The disclosed methods, systems, and techniques allow for improved nucleation rate and yield of clathrate hydrates. In some cases, the disclosed methods, systems, and techniques can also improve or reduce the amount of time needed for obtaining a given quantity of clathrate hydrate phase, for example, in desalination, gas separation and/or gas sequestration processes. The reactive metal nucleation substrate may include reactive metals from Group II, Group I, or Group XIII of the periodic table, for example, in alloyed form with other metals and/or nonmetal elements.

Described herein are methods, systems, and techniques relating to clathrate hydrate formation processes and, particularly, involving reactive metal nucleation substrates for promoting clathrate hydrate formation. The disclosed methods, systems, and techniques allow for improved nucleation rate and yield of clathrate hydrates. In some cases, the disclosed methods, systems, and techniques can also improve or reduce the amount of time needed for obtaining a given quantity of clathrate hydrate phase, for example, in desalination, gas separation and/or gas sequestration processes. The reactive metal nucleation substrate may include reactive metals from Group II, Group I, or Group XIII of the periodic table, for example, in alloyed form with other metals and/or nonmetal elements.

Some variations provide a system for producing a functionalized powder, comprising: an agitated pressure vessel; first particles and second particles contained within the agitated pressure vessel; a fluid contained within the agitated pressure vessel; an exhaust line for releasing the fluid from the agitated pressure vessel; and a means for recovering a functionalized powder containing the second particles disposed onto surfaces of the first particles. A preferred fluid is carbon dioxide in liquefied or supercritical form. The carbon dioxide may be initially loaded into the pressure vessel as solid carbon dioxide. The pressure vessel may be batch or continuous and is operated under reaction conditions to functionalize the first particles with the second particles, thereby producing a functionalized powder, such as nanofunctionalized metal particles in which nanoparticles act as grain refiners for a component ultimately produced from the nanofunctionalized metal particles. Methods for making the functionalized powder are also disclosed.

Some variations provide a system for producing a functionalized powder, comprising: an agitated pressure vessel; first particles and second particles contained within the agitated pressure vessel; a fluid contained within the agitated pressure vessel; an exhaust line for releasing the fluid from the agitated pressure vessel; and a means for recovering a functionalized powder containing the second particles disposed onto surfaces of the first particles. A preferred fluid is carbon dioxide in liquefied or supercritical form. The carbon dioxide may be initially loaded into the pressure vessel as solid carbon dioxide. The pressure vessel may be batch or continuous and is operated under reaction conditions to functionalize the first particles with the second particles, thereby producing a functionalized powder, such as nanofunctionalized metal particles in which nanoparticles act as grain refiners for a component ultimately produced from the nanofunctionalized metal particles. Methods for making the functionalized powder are also disclosed.

A valve assembly wherein the inner wall of the valve body comprises at least one opening for the entry of a liquid under pressure following output of a slurry or liquid from a tube or pipe. The valve assembly is particularly useful in maintaining a semi-continuous or continuous pressurized flow of biomass from an extruder and extending the reaction zone downstream from the extruder. An advantage of having an extended reaction zone allows for a complete treatment of materials without further wear on the extruder and also allows manipulation of the upstream treatment of materials in the tube or pipe.

A high-efficiency, low-energy consumption and environmental-friendly recycling technology for PETE plastic waste is disclosed. The degradation of PETE plastic waste includes a method for attacking the —O— ester linkage in the repeat unit of PETE plastic with water in saturated pressure and CO.sub.2 in supercritical (Sc) conditions.

A high-efficiency, low-energy consumption and environmental-friendly recycling technology for PETE plastic waste is disclosed. The degradation of PETE plastic waste includes a method for attacking the —O— ester linkage in the repeat unit of PETE plastic with water in saturated pressure and CO.sub.2 in supercritical (Sc) conditions.

An autoclave comprises an elongate chamber enclosing an interior atmosphere, a floor configured to support one or more objects, and a plenum extending through a portion of the elongate chamber. The plenum includes an inlet as well as a plurality of outlets. The inlet is configured to receive a plenum flow of the interior atmosphere, while each of the plurality of outlets is configured to release a portion of the plenum flow to a different locus of the elongate chamber.

An autoclave comprises an elongate chamber enclosing an interior atmosphere, a floor configured to support one or more objects, and a plenum extending through a portion of the elongate chamber. The plenum includes an inlet as well as a plurality of outlets. The inlet is configured to receive a plenum flow of the interior atmosphere, while each of the plurality of outlets is configured to release a portion of the plenum flow to a different locus of the elongate chamber.