Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/64—Alkaline compounds
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C1/00—Pretreatment of the finely-divided materials before digesting
  • D21C1/06—Pretreatment of the finely-divided materials before digesting with alkaline reacting compounds
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C3/00—Pulping cellulose-containing materials
  • D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
  • D21C9/10—Bleaching ; Apparatus therefor
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/38—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing crosslinkable groups
  • D21H17/39—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing crosslinkable groups forming ether crosslinkages, e.g. alkylol groups
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/53—Polyethers; Polyesters
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
  • D21H21/22—Agents rendering paper porous, absorbent or bulky
  • D21H21/24—Surfactants

Definitions

• Embodiments of the present disclosure relate generally to compositions useful for bleaching and methods of preparation and uses thereof.
• Bleaching compositions are generally introduced into pulp derived from wood or other lignocellulosic material during pulp processing to increase the brightness and/or whiteness of the pulp, and to remove lignin and other undesired materials.
• Bleaching compositions may be used to treat mechanical pulp, e.g. wood pulp, or chemical pulps.
• Bleaching is typically conducted with hydrogen peroxide under alkaline conditions.
• certain bleaching conditions are associated with negative effects such as high chemical oxygen demand (COD) and biochemical oxygen demand (BOD), e.g., given the causticity of chemicals used during bleaching.
• the present disclosure includes compositions useful in bleaching applications, including pulp processing, and methods of use thereof.
• the present disclosure includes a method for preparing a composition by combining a basic solution with a first slurry comprising an alkaline earth metal hydroxide and a dispersant; wherein the basic solution comprises from about 30% by weight to about 50% by weight, or from about 40% by weight to about 50% by weight of an alkali hydroxide; wherein the first slurry comprises from about 30% by weight to about 65% by weight, from about 35% by weight to about 55% by weight, or from about 35% by weight to about 45 % by weight of the alkaline earth metal hydroxide; and/or wherein the composition is in the form of a second slurry having a Brookfield viscosity below about 1000 mPa ⁇ s at least 24 hours after adding the basic solution to the first slurry.
• the alkaline earth metal hydroxide may comprise Mg(OH) 2 , Ca(OH) 2 , or a mixture thereof.
• the alkali hydroxide may comprise NaOH, KOH, or a mixture thereof.
• the weight ratio of alkaline earth metal hydroxide to alkali hydroxide in the composition may range from about 5:1 to about 20:1, from about 6:1 to about 12:1, or from about 8:1 to about 10:1.
• the basic solution may comprise from about 45% to about 50% by weight NaOH
• the first slurry may comprise from about 35% to about 45% by weight Mg(OH) 2 .
• the first slurry may comprise from about 0.5% by weight to about 2.5% by weight, or from about 1.0% by weight to about 1.5% by weight of the dispersant.
• An exemplary dispersant may comprise a polyether carboxylate, maleic acid-acrylic acid copolymer, or mixture thereof.
• the basic solution may be added to the first slurry over period of time ranging from about 0.005 g alkali hydroxide/min per g alkaline earth metal hydroxide to about 0.250 g alkali hydroxide/min per g alkaline earth metal hydroxide. Additionally or alternatively, the basic solution may be added to the first slurry over a period of time of greater than about 1 minute, greater than about 2 minutes, greater than about 3 minutes, greater than about 5 minutes, or a period of time ranging from about 1 minute to about 10 minutes or from about 5 minutes to about 10 minutes.
• the composition may be a second slurry having a total solids content ranging from about 40% to about 60% by weight.
• the composition may have a Ford cup emptying time of less than about 40 seconds, less than about 35 seconds, or less than about 30 seconds at least 24 hours after adding the basic solution to the slurry.
• the Brookfield viscosity of the composition may change by less than about 20% within 24 hours of adding the basic solution to the slurry.
• the pH of the composition may range from about 12.0 to about 14.0, or from about 13.0 to about 13.5.
• the present disclosure may also include a composition prepared according to any of the methods described above, or elsewhere herein.
• the composition may comprise water, a dispersant, Mg(OH) 2 , and NaOH, wherein the composition has a total solids content ranging from about 40.0% to about 60.0% by weight.
• the composition may be in the form of a slurry.
• the composition may have a Brookfield viscosity below about 1000 mPa ⁇ s. Additionally or alternatively, the Brookfield viscosity of the composition may range from about 500 mPa ⁇ s to about 800 mPa ⁇ s. In at least one example, the Brookfield viscosity of the composition may change by less than about 20% within 24 hours.
• the weight ratio of Mg(OH) 2 to NaOH in the composition may range from about 6:1 to about 12:1, or from about 8:1 to about 10:1.
• the composition may have a Ford emptying time of less than about 40 seconds, less than about 35 seconds, or less than about 30 seconds.
• the composition may have a pH ranging from about 12.0 to about 14.0.
• the present disclosure may also include use of the composition described above, or elsewhere herein, in a pulp bleaching process.
• the terms “comprises,” “comprising,” or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, composition, article, or apparatus that comprises a list of elements does not include only those elements, but may include other elements not expressly listed or inherent to such process, method, composition, article, or apparatus.
• the term “exemplary” is used in the sense of “example” rather than “ideal.”
• compositions useful for bleaching applications including, e.g. compositions comprising an alkaline slurry.
• the compositions herein may help to brighten and/or whiten pulp from wood or other lignocellulosic material during pulp processing.
• methods for preparation of such compositions e.g., having a relatively high solids content and a viscosity and stability suitable for use in pulp processing.
• the compositions herein may be in the form of an aqueous slurry.
• compositions according to the disclosure may be alkaline.
• the compositions herein may be prepared from a basic solution.
• the basic solution may comprise a strong base.
• the basic solution may comprise an alkali hydroxide, such as, e.g., NaOH, KOH, LiOH, or a mixture thereof.
• the basic solution may comprise from about 25% by weight to about 50% by weight of at least one alkali hydroxide, such as from about 35% by weight to about 45% by weight, or from about 40% by weight to about 50% by weight of the alkali hydroxide.
• the basic solution may have a concentration ranging from about 5.5 M to about 19.0 M, such as from about 7.0 M to about 15.0 M, from about 12.0 M to about 17.0 M, or from about 12.0 M to about 19.0 M.
• the basic solution comprises NaOH having a concentration ranging from about 10.0 M to about 19.0 M, from about 6.5 M to about 12.0 M, from about 7.0 M to about 11 M, from about 8.0 M to about 12.0 M, from about 10.0 M to about 16.0 M, or from about 10.0 M to about 12.5 M.
• the basic solution comprises KOH having a concentration ranging from about 5.5 M to about 12.0 M, from about 7.0 M to about 10.0 M, or from about 10.0 M to about 12.0 M.
• the basic solution is free from sodium silicate.
• the composition may further comprise an alkaline earth metal hydroxide and/or an alkaline earth metal oxide, which may be present as an aqueous slurry.
• the basic solution may be combined with a first slurry comprising the alkaline earth metal hydroxide and/or oxide to produce a composition in the form of a second slurry having a pH higher than the first slurry.
• the first slurry (comprising alkaline earth metal(s)) may have a relatively high solids content.
• the amount of alkaline earth metal hydroxide and/or oxide in the first slurry may range from about 30% by weight to about 65% by weight, from about 35% by weight to about 55% by weight, or from about 35% by weight to about 45 % by weight of the first slurry.
• Exemplary alkaline earth metal hydroxides and oxides include, but are not limited to, Mg(OH) 2 , Ca(OH) 2 , MgO, CaO, and mixtures thereof.
• the first slurry is an aqueous slurry comprising from about 30% to about 65% by weight Mg(OH) 2 .
• the first slurry may further comprise at least one dispersant.
• the dispersant may be cationic, anionic, or nonionic.
• Exemplary dispersants include, but are not limited to, polyether carboxylates, polyether polycarboxylates, and acrylate polymers and copolymers (e.g., maleic acid-acrylic acid copolymers, maleic acid copolymers, etc.).
• the first slurry may comprise from about 0.5% by weight to about 2.5% by weight of the at least one dispersant, such as, e.g., from about 0.75% by weight to about 1.75% by weight, or from about 1.0% by weight to about 1.5% by weight of the dispersant(s).
• the first slurry comprises Mg(OH) 2 and a dispersant chosen from a polyether carboxylate or maleic acid acrylic acid copolymer.
• compositions herein may be prepared by adding, or otherwise combining, the first slurry (comprising alkaline earth metal(s)) with the basic solution to produce a second slurry. Due to the relatively high solids content of the first slurry, the manner in which the basic solution and the first slurry are combined can result in mixtures with different rheological properties. In some cases, the resulting rheological properties of the mixture may be unsuitable for bleaching, such as mixtures having the consistency of a gel rather than a liquid.
• the basic solution may be combined with the first slurry at a controlled rate, e.g., to avoid gelling of the liquid.
• the rate at which the basic solution is added may be selected based at least partially on the concentration of the first slurry, the concentration of the basic solution, or both.
• the basic solution may be added more slowly to slurries with a relatively higher solids content.
• the rate may be generally described as "very fast” when the full volume of basic solution is added in less than 10 seconds, “fast” when the full volume of basic solution is added in a time period ranging from 10 seconds to 30 seconds, “slow” when the full volume of basic solution is added in a time period ranging from 30 seconds to 2 minutes, and “very slow” when the full volume of basic solution is added over a period of time greater than about 2 minutes, or greater than about 3 minutes, or greater than about 5 minutes, or greater than about 10 minutes.
• the basic solution may be added to the first slurry at a rate ranging from about 0.1 g alkali hydroxide/min to about 5.0 g alkali hydroxide/min, such as from about 0.5 g alkali hydroxide/min to about 4.0 g alkali hydroxide/min, from about 1.5 g alkali hydroxide/min to about 3.0 g/min, or from about 0.8 g alkali hydroxide/min to about 4.0 g alkali hydroxide/min.
• 16 g of a 50% by weight solution of NaOH may be added to a slurry comprising 30-60% Mg(OH) 2 by weight over a period of time ranging from about 30 seconds to about 10 minutes at a rate of about 1.6-32.0 g NaOH solution/min.
• the basic solution may be added to the first slurry at a rate at least partially dependent on the amount of alkaline earth metal hydroxide in the first slurry.
• the basic solution may be added to the first slurry at a rate ranging from about 0.005 g to about 0.250 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry, such as from about 0.010 g to about 0.200 g alkali hydroxide/min per g alkaline earth metal hydroxide, from about 0.050 g to about 0.150 g alkali hydroxide/min per g alkaline earth metal hydroxide, or from about 0.010 g to about 0.050 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry.
• the basic solution may be added at a rate ranging from about 0.010 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry to about 0.100 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry, from about 0.011 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry to about 0.070 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry, from about 0.012 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry to about 0.060 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry, from about 0.014 g alkali hydroxide/min per g alkaline earth metal hydroxide in the first slurry to about 0.056 g alkali hydrox
• the basic solution may be added to the first slurry at a rate based on the content of the produced composition (e.g., a second slurry).
• the second slurry may comprise from about 5% by weight to about 15% by weight of alkali hydroxide, such as, e.g., from about 7% by weight to about 13% by weight, from about 8% by weight to about 12% by weight, or from about 9% by weight to 11% by weight of alkali hydroxide.
• the basic solution may be added to the first slurry over a period of time ranging from about 30 seconds to about 10 minutes, from about 40 seconds to about 9 minutes, from about 1 minute to about 7 minutes, from about 2 minutes to about 5 minutes, or from about 2 minutes to about 10 minutes.
• the basic solution may be added to the first slurry over a period of time greater than 1 minute, e.g.
• composition comprises from about 5% by weight to about 15% by weight of alkali hydroxide, e.g., from about 7% by weight to about 13% by weight, from about 8% by weight to about 12% by weight, or from about 9% by weight to 11% by weight of alkali hydroxide.
• the basic solution may be added to the first slurry over a certain period of time.
• the basic solution may be added to the first slurry over a period of time ranging from about 30 seconds to about 10 minutes, from about 40 seconds to about 9 minutes, from about 1 minute to about 7 minutes, from about 2 minutes to about 5 minutes, or from about 2 minutes to about 10 minutes.
• the basic solution may be added to the first slurry over a period of time greater than 1 minute, e.g. greater than 2 minutes, greater than 3 minutes, greater than 5 minutes, or greater than 10 minutes.
• the rate at which the basic solution and the slurry of alkaline earth metal hydroxide and/or oxide are combined may assist in maintaining rheological properties suitable for bleaching processes.
• the resulting composition may maintain a viscosity suitable for combination with other agents (e.g., oxidizing/bleaching agents) during bleaching.
• the Brookfield viscosity of the resulting composition (second slurry) may be less than or equal to 1000 MPa ⁇ s, e.g., the composition having a sufficiently liquid-like consistency for use in a bleaching process.
• Such compositions may be beneficial in efficiently producing paper with a desired brightness.
• Agitation may be used to incorporate the basic solution and the first slurry.
• the first slurry may be stirred, e.g., with a stirrer bar or other suitable agitation, during the addition of the basic solution.
• the basic solution and first slurry may be combined at a temperature ranging from about 10°C to about 35°C, such as at or near room temperature (e.g., from about 20°C to about 25°C).
• Adding the basic solution to the first slurry may raise the pH of the first slurry such that the resulting composition (second slurry) exhibits a pH above 10.2.
• the pH of the second slurry may range from about 12.0 to about 14.0, from about 12.2 to about 13.8, from about 12.5 to about 13.7, or from about 13.0 to about 13.5.
• the higher pH may result in a faster bleaching process and consequently also in improved brightness/whiteness as compared to a pH of 10.2 or less.
• the weight ratio of alkaline earth metal hydroxide to alkali hydroxide in the composition may range from about 5:1 to about 20:1, such as from about 6:1 to about 12:1, or from about 8:1 to about 10:1.
• the composition may comprise NaOH and Mg(OH) 2 having a weight ratio of Mg(OH) 2 to NaOH ranging from about 6:1 to about 12:1, or from about 8:1 to about 10:1.
• the composition may have a total solids content ranging from about 30% by weight to about 65% by weight, about 40% by weight to about 60% by weight, or about 45% by weight to about 55% by weight.
• the composition may optionally comprise one or more additives such as, e.g., pH buffering agents, bleaching agents, chelating agents, and/or surfactants.
• the composition does not include stabilizing agents such as silicate.
• the composition does not comprise sodium silicate.
• the rheological properties of the composition may be characterized by its Brookfield viscosity and Ford cup emptying time. Brookfield viscosity may be determined according to ISO 2884-2: 2003. For example, the composition may be allowed to stabilize at room temperature and then poured into a glass cell with a spindle. Then a Brookfield viscometer may rotate the spindle at 100 rpm within the second slurry to measure a maximum torque. The maximum torque may be used to calculated the Brookfield viscosity. In some examples, the composition may have a Brookfield viscosity less than or equal to about 1000 mPa ⁇ s at least 24 hours after adding the basic solution to the first slurry.
• the Brookfield viscosity may range from about 450 mPa ⁇ s to about 900 mPa ⁇ s, from about 500 mPa ⁇ s to about 800 mPa ⁇ s, or from about 650 mPa ⁇ s to about 750 mPa ⁇ s at least 24 hours after adding the basic solution to the first slurry.
• the Brookfield viscosity of the composition may be steady or change relatively little over time. In some examples, the Brookfield viscosity of the composition changes by less than about 25%, less than about 20%, or less than about 15% within 24 hours of adding the basic solution to the first slurry. In certain examples, the Brookfield viscosity of the composition may increase or decrease by less than about 20%, less than about 15%, or less than about 10% within 24 hours of adding the basic solution to the first slurry. In at least one example, the Brookfield viscosity of the composition does not increase within 24 hours of adding the basic solution to the first slurry.
• the Ford cup emptying time provides another indication of the viscosity of the composition and may be measured according to ASTM D1200.
• ASTM D1200 ASTM D1200.
• the composition is added to a Ford cup No. 4, having an opening in the bottom of the cup that allows the composition to flow out of the cup under the force of gravity.
• the composition may have a Ford cup emptying time of less than 40 seconds, less than 35 seconds, or less than 30 seconds at least 24 hours after adding the basic solution to the first slurry.
• the composition may have a Ford cup emptying time ranging from 5 seconds to 40 seconds, from 5 seconds to 25 seconds, or from 10 seconds to 15 seconds.
• the composition may be an aqueous slurry having a solids content of at least 30% that is prepared and stored in a container before use in a bleaching process.
• the composition may be stored in a container ranging from 1 L to 200 L in volume, e.g., from about 1 L to about 10 L, or from about 25 L to about 200 L.
• the composition may be stored in intermediate bulk containers (IBL's) or bulk containers of 500 L or more, e.g., ranging from about 500 L to about 2000 L, or from about 1000 L to about 1250 L in volume.
• the composition may be stored in shipping containers; e.g. tank cars, sea containers, or other intermodal containers.
• compositions herein may be useful for a number of applications, including the pulp bleaching and the papermaking process.
• the compositions herein may fully or partially replace other alkaline agents as part of the bleaching process.
• compositions A, B, and C were prepared from a slurry comprising Mg(OH) 2 and a dispersant that was combined with NaOH solution as summarized in Table 1.
• a stock slurry comprising 53% by weight Mg(OH) 2 and about 1% polyether-polycarboxalate dispersant was used.
• the stock slurry was diluted to a concentration of 39.1% by weight Mg(OH) 2 with water.
• NaOH solution (12.5% or 50% by weight) was added to each slurry in a beaker over a certain period of time (greater than 2 minutes or less than 1 minute) to produce the respective compositions.
• compositions D, E, and F were then prepared to test the effects of dilution. These compositions were prepared as discussed above with respect to compositions A-C, except for compositions D and E, water was added after mixing the slurry and NaOH solution, and for composition F, water was added to the slurry before adding NaOH. See Table 2 below.
• compositions A-E were sufficiently liquid-like (as opposed to gel-like) for use in bleaching applications, e.g., exhibiting viscosities less than 1000 mPa ⁇ s. While compositions D and E initially had a higher viscosity, the respective values decreased over the 24-hour period following preparation. Composition F had the highest viscosity, and likely would not be suitable for use in a bleaching process or cause problems in handling the slurry such as pumping or stirring. Moreover, comparison of compositions B and C, which had the same amounts of NaOH and Mg(OH) 2 , suggests that the rate at which NaOH is added to Mg(OH) 2 has an effect since NaOH was added at a slower rate for composition B.
• composition B exhibited a lower viscosity than composition C, and the viscosity of composition B did not increase within the 24-hour period. Further compositions A-C maintained relatively stable viscosities over time as compared to compositions D-F prepared with a dilution step.
• compositions G, H and I are prepared with MgO in place of, or in addition to, Mg(OH) 2 .
• MgO is added to water in a beaker and mixed to form a slurry.
• MgO is slightly soluble in water ( ⁇ 0.009 g per 100 mL water) to produce Mg(OH) 2 .
• Mg(OH) 2 is also added to form the slurry.
• a 50% by weight NaOH solution is slowly added with agitation.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Detergent Compositions (AREA)
• Paper (AREA)

Priority Applications (1)

Applications Claiming Priority (1)

Publications (1)

Family

ID=62217908

Family Applications (1)

Country Status (1)

Citations (2)

• 2018
  • 2018-05-10 EP EP18305577.1A patent/EP3567158A1/fr not_active Ceased

Patent Citations (2)

Similar Documents

Legal Events