A process for isolating lignin from an alkaline process stream of thickened black liquor which is introduced continuously into a lower region of at least one circulation reactor having two reactor zones in concentric arrangement, liquid level of the alkaline process stream in the interior of the reactor is at a level with an upper end of an inner tubular reactor zone, a CO.sub.2-containing gas is blown continuously from the bottom into the inner tubular reactor zone of the reactor, wherein the CO.sub.2-containing gas is absorbed by the alkaline process stream in the inner circulation reactor zone and offgas is drawn off with residual amounts of the CO.sub.2 at the top of the reactor, the process is run at 1 atm, and thickened black liquor with a reduced lignin content together with precipitated lignin present are drawn off optionally after settling at the base of the reactor.

A textile recycling method receives textile-waste-to-be-recycled, sorts the waste to isolate cellulose-containing articles from non-cellulose-containing articles, and re-sizes at least some of the cellulose-containing articles to create feedstock. The feedstock is processed in a cellulose solvent reactor, which has at least one ionic liquid. The ionic liquid dissolves intermolecular cellulose bonds of the feedstock to create a spinning dope. Cellulose fibers dissolved in the cellulose-bearing spinning dope solution are extruded in a cellulose coagulation bath reservoir to reconstitute at least some of the cellulose fibers, and the reconstituted fibers are wet-spun to form a continuous cellulose thread that is commercially indistinguishable from virgin fiber thread. Synthetic fiber material is vacuum-extracted or mechanically extracted from the cellulose-bearing solution and recycled into a continuous synthetic thread. Original color of textile-waste-to-be-recycled can be retained or removed, and new color can be added.

A reactor arrangement for pre-hydrolysis of biomass material. The reactor arrangement comprises a reactor vessel arranged substantially horizontally, wherein the vessel comprises an inlet for receiving the biomass material arranged at an upper portion of the vessel. The inlet may be arranged at a first longitudinal end of the vessel. The vessel may furthermore comprise an outlet at a second longitudinal end of the vessel. The reactor arrangement further comprises a set of steam injection orifices arranged to inject or supply steam into the reactor vessel. The set of steam injection orifices comprises at least two orifices arranged below the inlet at a distance from each other. The at least two orifices may be arranged at a distance from each other in the lateral direction of the reactor vessel. Furthermore, a method for pre-hydrolysis treatment of biomass in a substantially horizontal reactor vessel is provided.

The present invention involves an environmentally friendly process and apparatus for the delignification of lignin-containing materials, such as cardboard newspaper or agricultural or tree pruning wastes. This process produces cellulose using low temperatures and low concentrations of hydrogen peroxide. It can be performed using a column fitted with a semipermeable gasket that pressurizes the column by retaining oxygen released by action of the hydrogen peroxide on a lignin-containing material.

The present invention involves an environmentally friendly process and apparatus for the delignification of lignin-containing materials, such as cardboard newspaper or agricultural or tree pruning wastes. This process produces cellulose using low temperatures and low concentrations of hydrogen peroxide. It can be performed using a column fitted with a semipermeable gasket that pressurizes the column by retaining oxygen released by action of the hydrogen peroxide on a lignin-containing material.

A bale of sheets made of virgin cellulose fibers and cellulose ester (CE) staple fibers can be fed to a hydropulper. The CE staple fibers have: i. a denier per filament (DPF) of less than 3, or ii. a cut length of less than 6 mm, or iii. crimping, or iv. a combination of any two or more of (i)-(iii). The bales can be fed and dropped in as entire bales to a hydropulper, or a blend tank directly or indirectly in fluid communication with a hydropulper, using the same feed system employed for feeding cellulose to the hydopulper and avoiding having to defiberize by pulling or drawing fibers from a box container into a hydropulper.

The present invention involves an environmentally friendly process and apparatus for the delignification of lignin-containing materials, such as cardboard newspaper or agricultural or tree pruning wastes. This process produces cellulose using low temperatures and low concentrations of hydrogen peroxide. It can be performed using a column fitted with a semipermeable gasket that pressurizes the column by retaining oxygen released by action of the hydrogen peroxide on a lignin-containing material.

The present invention involves an environmentally friendly process and apparatus for the delignification of lignin-containing materials, such as cardboard newspaper or agricultural or tree pruning wastes. This process produces cellulose using low temperatures and low concentrations of hydrogen peroxide. It can be performed using a column fitted with a semipermeable gasket that pressurizes the column by retaining oxygen released by action of the hydrogen peroxide on a lignin-containing material.

A process for isolating lignin from an alkaline process stream of thickened black liquor which is introduced continuously into a lower region of at least one circulation reactor having two reactor zones in concentric arrangement, liquid level of the alkaline process stream in the interior of the reactor is at a level with an upper end of an inner tubular reactor zone, a CO.sub.2-containing gas is blown continuously from the bottom into the inner tubular reactor zone of the reactor, wherein the CO.sub.2-containing gas is absorbed by the alkaline process stream in the inner circulation reactor zone and offgas is drawn off with residual amounts of the CO.sub.2 at the top of the reactor, the process is run at 1 atm, and thickened black liquor with a reduced lignin content together with precipitated lignin present are drawn off optionally after settling at the base of the reactor.

A method and system to produce treated Cellulose Filaments (CF) and CF products are provided. Feedstock comprising CF in a water solution are mixed with a debonder to produce a mixed stream. The mixed stream is filtered yielding separate filtered and filtrate streams. The filtrate stream comprises at least a portion of the debonder. The filtered stream is dried to produce treated CF. The debonder is one of an alcohol, glycol ether, ester-containing quaternary ammonium salt, amido amine quaternary ammonium salt, disubstituted amide or a mixture thereof. The filtrate stream may be recycled. The mixed stream may be washed before filtering to remove debonder. A thermoplastic polymer-treated Cellulose filament composite material is formable by associating the treated CF with a thermopolymer such as polyolefin, polyurethane (PU), polypropylene (PP), polyester (PE), polylactic acid (PLA), polyhydroxyalkanoates (PHA), polyamide (PA), and ethylene vinyl acetate (EVA) or a mixture.