Abstract: Conductive coating compositions and methods of preparation and application thereof are provided, whereby a mixture of conductive polymer encapsulated particles and non-encapsulated particles are employed to provide a conductive surface coating with controllable viscosity and conductivity. The particles may be filler and/or pigment particles such as calcium carbonate or clay, a portion of which are coated with a conductive polymer such as polypyrrole. Encapsulated particles are prepared and filtered, mixed with non-encapsulated particles, and subsequently combined with a binder for application to a surface or substrate such as paper. A dispersant may be included to obtain a suitable viscosity of the mixture prior to application. The relative concentrations of the encapsulated and non-encapsulated particles may be selected to tailor the resulting conductivity of the coating.

Abstract: The present disclosure relates to an antenna, comprising (a) substrate; and (b) a composition, comprising, (i) an electrically conductive material; and (ii) a binder; wherein the composition is adjacent to the substrate.

Abstract: The present disclosure relates to anti-static articles and multi-layered materials comprising an electrically conductive layer and a support layer.

Abstract: A method of preparing dissolving pulp. The method includes physically separating a kraft pulp or a kraft hydrolysis pulp into first and second fractions, the first fraction having a relatively low lignin content and the second fraction having a relatively high lignin content.

Abstract: Systems and methods are provided for refining and reclaiming rejects in a sulfite pulping process. Wood chips and sulfite cooking liquor are provided to a digester for delignification. The slurry obtained from the digester is screened to obtain a reject portion containing sulfite rejects. The sulfite rejects are disintegrated in a refiner, such that the rejects are refined to a freeness suitable for digestion in a subsequent re-cooking step. Refined rejects are then returned to the digester for re-cooking with wood chips.

Abstract: Systems and methods are provided for refining and reclaiming rejects in a sulfite pulping process. Wood chips and sulfite cooking liquor are provided to a digester for delignification. The slurry obtained from the digester is screened to obtain a reject portion containing sulfite rejects. The sulfite rejects are disintegrated in a refiner, such that the rejects are refined to a freeness suitable for digestion in a subsequent re-cooking step. Refined rejects are then returned to the digester for re-cooking with wood chips.

Abstract: A process for improving optical properties of high-yield pulp (HYP) for producing paper products with superior brightness. Optical brightening agents (OBAs) can effectively improve the optical properties of high-yield pulp (HYP). The present process involves incorporating the OBAs into the alkaline peroxide bleaching process. By combining peroxide bleaching with an optical brightening agent, one can decrease the bleaching cost to reach the same brightness target. Some key advantages of adding OBA to HYP at the pulp mill over the conventional wet-end addition of OBA include: i) the quenching effect on OBA by the wet-end cationic polymers such as PEI is decreased by fixing OBA on HYP fibers; ii) the negative impact of metal ions in the white water system on the OBA performance is minimized when OBA is pre-adsorbed and fixed on HYP fibers; iii) the photo-yellowing (color reversion) of HYP and HYP-containing paper sheets is decreased when more OBA is on HYP fibers to protect them from harmful UV radiation.

Abstract: Methods are provided for the recovery of dissolved organics, such as hemicelluloses, lignin, and acetic acid, from a lignocellulosic feedstock or process liquor, where the dissolved organics are recovered via an adsorbent. The adsorbent may include activated carbon, modified activated carbon, precipitated calcium carbonate, and lime and/or lime mud. The dissolved organics may be adsorbed from a pre-hydrolysis liquor of a pulping process such as the Kraft-based dissolving pulp production process. Other methods include a combined (or integrated) process of adsorption, ion exchange resin treatment, and membrane filtration for the treatment of a lignocellulosic liquor, such as a pre-hydrolysis liquor of kraft-based dissolving pulp production process, such that dissolved organics such as lignin, acetic acid, and hemicellulose-derived sugars may be extracted and optionally concentrated.

Abstract: The present invention provides electrically conductive paper composites prepared from cellulose fibers modified to bind a conducting polymer to a surface of the cellulose fibers and mixing these with unmodified cellulose fibers and forming paper products from the composite. Conducting paper composites so formed were investigated for their conductivity and strength properties as a function of monomer dosage or percentage of modified fibers in the mixture and for the composites it was found that less monomer (i.e. conductive polymer) was needed to achieve the same conductivity obtained from conducting paper made from only the modified cellulose. A higher tensile strength was obtained with the composite conducting paper than was attained with conducting paper made from only the modified cellulose. The electrically conductive paper composites may also be prepared from cellulose fibers mixed with particulate fillers modified to bind a conducting polymer to a surface of the particulate fillers.

Abstract: The present invention provides an improved process for chlorine dioxide bleaching of chemical pulps in an aqueous suspension, which uses magnesium hydroxide or magnesium oxide. The process involves the addition of magnesium hydroxide or magnesium oxide to the pulp, in addition to chlorine dioxide, maintaining the mixture at a pH between about 2.5 to 7.5 for about 1 or more hours, most suitably between about 1-4 hours. This process can be used in the D1 or D2 stage of a typical D0EopD1E2D2 bleaching sequence, as well as in the chlorine dioxide brightening stage of other three, four, five, and six-stage bleaching sequences of either the so-called ECF process, or those containing elemental chlorine (Cl2). The temperature is between about 40 to about 90° C., and the pulp consistency is between about 1 to about 16%.

Abstract: A process for improving optical properties of high-yield pulp (HYP) for producing paper products with superior brightness. Optical brightening agents (OBAs) can effectively improve the optical properties of high-yield pulp (HYP). The present process involves incorporating the OBAs into the alkaline peroxide bleaching process. By combining peroxide bleaching with an optical brightening agent, one can decrease the bleaching cost to reach the same brightness target. Some key advantages of adding OBA to HYP at the pulp mill over the conventional wet-end addition of OBA include: i) the quenching effect on OBA by the wet-end cationic polymers such as PEI is decreased by fixing OBA on HYP fibers; ii) the negative impact of metal ions in the white water system on the OBA performance is minimized when OBA is pre-adsorbed and fixed on HYP fibers; iii) the photo-yellowing (color reversion) of HYP and HYP-containing paper sheets is decreased when more OBA is on HYP fibers to protect them from harmful UV radiation.

Abstract: The present invention provides electrically conductive paper composites prepared from cellulose fibers modified to bind a conducting polymer to a surface of the cellulose fibers and mixing these with unmodified cellulose fibers and forming paper products from the composite. Conducting paper composites so formed were investigated for their conductivity and strength properties as a function of monomer dosage or percentage of modified fibers in the mixture and for the composites it was found that less monomer (i.e. conductive polymer) was needed to achieve the same conductivity obtained from conducting paper made from only the modified cellulose. A higher tensile strength was obtained with the composite conducting paper than was attained with conducting paper made from only the modified cellulose. The electrically conductive paper composites may also be prepared from cellulose fibers mixed with particulate fillers modified to bind a conducting polymer to a surface of the particulate fillers.

Abstract: There is provided a new and useful process for peroxide bleaching of mechanical or high yield pulp, the process comprising adding to a pulp slurry at least one stabilizer for stabilizing low valency states of transition metal ions in the slurry; subsequently adding caustic soda to said slurry simultaneously with or subsequent to adding said at least one stabilizer; adding hydrogen peroxide to the slurry at a preselected point; and subjecting the slurry to preselected conditions to complete the bleaching process.

Abstract: A process for peroxide bleaching of mechanical or high yield pulp, the process comprising adding to a pulp slurry at least one stabilizer for stabilizing low valency states of transition metal ions in the slurry; subsequently adding caustic soda to said slurry simultaneously with or subsequent to adding said at least one stabilizer; adding hydrogen peroxide to the slurry at a preselected point; and subjecting the slurry to preselected conditions to complete the bleaching process.

Abstract: The present invention relates to a method for bleaching mechanical and chemithermomechanical pulp including that an advancing pulp suspension obtained after that the fibres are laid free is prebleached by adding reductive bleaching agent to the pulp suspension in a location just after the fibres are laid free and that the bleaching is carried out under given conditions in the form of high temperature and minimized oxygen access in respect of said adding location and immediately downstream of said location, characterized in, that the in the described manner prebleached pulp is subjected to at least one further bleaching treatment including that the pulp is bleached with an oxidizing bleaching agent, preferably peroxide bleaching agent, reinforced with borohydride.

Abstract: There is provided a new and useful process for peroxide bleaching of mechanical or high yield pulp, the process comprising adding to a pulp slurry at least one stabilizer for stabilizing low valency states of transition metal ions in the slurry; subsequently adding caustic soda to said slurry simultaneously with or subsequent to adding said at least one stabilizer; adding hydrogen peroxide to the slurry at a preselected point; and subjecting the slurry to preselected conditions to complete the bleaching process.

Abstract: A single stage method delignification process for pulps, preferably sulphite pulps. The improvement to conventional oxygen delignification process comprises in situ addition of a reducing agent substantially non-reactive with oxygen. The end result is a pulp having enhanced strength properties and higher viscosity. Sodium borohydride is the preferred reducing agent, and MgO is the preferred alkali source. Similar results can be obtained with a two-stage oxygen delignification wherein the pulp is treated with the reducing agent in the first stage, and then washed and pressed conventionnally before proceeding with the oxygen delignification in a second stage.

Abstract: A bleached pulp having a high viscosity for a given permanganate number is formed by pretreating never dried pulp with an organic solvent medium to produce a treated pulp composed of said never dried pulp in the medium and then bleaching that treated pulp using ozone at a pH of 1.5-5 to provide a bleached pulp while reducing the viscosity loss during the ozone bleaching step significantly compared to that what would occur if the medium used in the ozone bleaching were water.

Abstract: A method of bleaching a chemical pulp with a gaseous bleaching agent by uniformly impregnating the pulp with a solvent for lignin and that is fully miscible with water but does not significantly swell cellulose so that the availability, of lignin to the bleaching agent is significantly improved, then subjecting the impregnated pulp to the action of the bleaching agent to preferentially attack the lignin for its subsequent solubilization and separation from the pulp.