EP0855995A2 - Adjuvants du beton a base de lignine sulfomethylolatee - Google Patents

Adjuvants du beton a base de lignine sulfomethylolatee

Info

Publication number
EP0855995A2
EP0855995A2 EP96938620A EP96938620A EP0855995A2 EP 0855995 A2 EP0855995 A2 EP 0855995A2 EP 96938620 A EP96938620 A EP 96938620A EP 96938620 A EP96938620 A EP 96938620A EP 0855995 A2 EP0855995 A2 EP 0855995A2
Authority
EP
European Patent Office
Prior art keywords
lignin
admixture
sulfomethylolated
concrete
composition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96938620A
Other languages
German (de)
English (en)
Other versions
EP0855995A4 (fr
Inventor
Theodore Bremner
Jiri Zhor
Gopal C. Goyal
Jairo H. Lora
Albert Creamer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alcell Technologies Inc
Original Assignee
Alcell Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alcell Technologies Inc filed Critical Alcell Technologies Inc
Publication of EP0855995A2 publication Critical patent/EP0855995A2/fr
Publication of EP0855995A4 publication Critical patent/EP0855995A4/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
    • C04B24/16—Sulfur-containing compounds
    • C04B24/18—Lignin sulfonic acid or derivatives thereof, e.g. sulfite lye
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates

Definitions

  • Cement compositions are brought into a workable form by mixing the solid components with an amount of water which is greater than that required to hydrate the cement components therein.
  • the mixed mineral binder composition is poured into a form and allowed to harden at atmospheric temperature. During the hardening, some of the excess water remains, leaving cavities in the formed structural unit and, thus, reduces the mechanical strength of the resultant unit. It is well known that the compressive strength of the resultant structure generally bears an inverse relationship to the water-cement ratio of the starting mix. The need to use smaller quantities of water is limited by the required flow and workability properties of the fresh mixture.
  • Concrete admixtures refer to compounds and compositions added to concrete mixtures to alter their properties.
  • Water-reducing agents have been used as concrete admixtures. They are generally used to improve workability while decreasing water addition so that a stronger and more durable concrete is obtained. Water-reducing agents are classified by their ability to reduce water content as superplasticizers or high-range water reducers and plasticizers or normal-range water reducers. Plasticizers and superplasticizers are made using chemicals with surface-active characteristics.
  • One of the traditional resources for the manufacture of water-reducing admixtures for concrete are the waste products from the pulp and paper industry, namely lignin and its derivatives.
  • Lignin-type water-reducing agents are well known for use in preparing concrete mixes. Such agents serve to reduce the amount of water that would ordinarily be required to make a pourable mix, without however disturbing most of the other beneficial properties of the mix. On various occasions, however, the use of such water-reducing agents may entrain air into the mix. Entrained air (from any source) tends to reduce compressive strength. As a general rule, with every one volume percent air in the concrete, 5% of strength is lost. Thus, 5o air means about 25% strength loss. However, air entrainment may be desirable in certain applications such as the manufacture of concrete blocks. Lignosulfonates are also known to slow down the curing of concrete thus causing what is known in the art as set retardation. Set retardation is particularly increased when the lignosulfonate contains impurities such as wood sugars.
  • Lignosulfonates are classified as anionic surfactants since the hydrophilic groups associated with the organic polymers are sulfonates. It has been reported that when absorbed onto cement particles, these surfactants impart a strong negative charge which lowers the surface tension of the surrounding water and greatly enhances the fluidity of the system. Lignosulfonates also exhibit set retarding properties. Lignosulfonates, when used in an amount sufficient to furnish the desired water reduction in a mix, normally entrain more air than desired and retard the setting time of concrete far beyond the ranges for a high-range water-reducing admixture.
  • Lignosulfonate-based concrete admixtures are usually prepared from the waste liquor formed by the production of sulfite pulp. By neutralization, precipitation and fermentation of this liquor a range of lignosulfonates of varying purity, composition and molecular weight distribution is produced. A number of researchers have reported several attempts to enhance the lignosulfonates so that they would meet the requirements of a superplasticizer as a h gh range water-reducing admixture. To date no purely lignosulfonate based superplasticizer for concrete has been placed on the market.
  • U.S. Pat. No. 4,239,550 is disclosed a flowing agent for concrete and mortar based on lignin sulfonate and on ⁇ ng-sulfonated or sulfo ethylolated aromatic substances.
  • the flowing agent imparts to concrete or mortar high fluidity without leading to undesirably long setting times.
  • 4,460,720 is disclosed a superplasticizer cement admixture for portland cement based compositions formed from a low molecular weight alkali metal poly-acrylate in combination with an alkali metal or alkaline earth metal poly-naphthalene sulfonate-formaldehyde or an alkali metal lignosulfonate or an alkaline earth metal lignosulfonate or mixtures thereof.
  • a superplasticizer cement admixture for portland cement based compositions formed from a low molecular weight alkali metal poly-acrylate in combination with an alkali metal or alkaline earth metal poly-naphthalene sulfonate-formaldehyde or an alkali metal lignosulfonate or an alkaline earth metal lignosulfonate or mixtures thereof.
  • 4,623,682 is disclosed cement mixes having extended workability without substantial loss in rate of hardening when containing an admixture combination of a sulfonated naphtalene-formaldehyde condensate and fractionated sulfonated lignin such as ultra-filtered lignosulfonate.
  • a sulfonated naphtalene-formaldehyde condensate and fractionated sulfonated lignin such as ultra-filtered lignosulfonate.
  • U.S. Pat. No. 4,351,671 is disclosed an additive for lignin type water-reducing agent which reduces air entrainment in the concrete mix
  • U.S. Pat. No. 4,367,094 is disclosed an agent for preventing deterioration in the slump properties of mortar concrete, containing as a mam ingredient a lignin sulfonate.
  • an environmentally friendly organosolv lignin-based superplasticizing and water-reducing admixture composition By the methods of the present invention is provided an environmentally friendly organosolv lignin-based superplasticizing and water-reducing admixture composition.
  • the superplasticizer admixture compositions of the invention can impart a high degree of fluidity to cement compositions, can cause retention of the fluidity over extended time and can achieve these results at low dosages.
  • By manipulation of the conditions for the manufacture of the admixture it is possible to obtain products that do not have an adverse effect on set retardation.
  • the lignin-based admixtures of this invention are high in purity and free of sugar contamination.
  • the invention provides for a novel lignin-based admixture produced from derivatized organosolv lignin.
  • This lignin-based admixture uses a coproduct from an environmentally friendly process while fulfilling a need in the construction industry.
  • the novel lignin-based admixture is produced by derivatizing organosolv lignin by treating the lignin in a sulfomethylolation step.
  • the derivatized lignin can be formulated with an air detrainer and the resulting admixture when added to concrete mixes effectively functions as a superplasticizer and as a high-range water reducer.
  • the lignin which can be employed in this invention is a high purity lignin, particularly an organosolv lignin.
  • the purity of the lignin in the present invention is from about 85 to about 100 p o.
  • the lignin is separated as a by-product of the pulping and chemical delignification of plant biomass with organic solvents, for example ethanol.
  • Organosolv lignin is a nontoxic, free-flowing powder. It is soluble in aqueous alkali and in selected organic solvents. It is generally characterized by its hydrophobicity, high purity, melt flow and a low level of carbohydrates and inorganic contaminants.
  • organosolv lignins such as regular ALCELL® lignin or low molecular weight ALCELL ⁇ lignin.
  • the regular ALCELL® lignin can be characterized by a number average molecular weight of about 700 to 1500 g/mol and the low molecular weight ALCELL® lignin can be characterized by a low average molecular weight in the range of less than 600 g/mol.
  • organosolv lignins Alternatively to organosolv lignins, it is believed that high purity lignins such as steam explosion or soda lignins can be suitable to accomplish the objectives of the invention.
  • the organosolv lignins of the invention can be derivatized using a sulfomethylolation procedure. Before carrying the sulfomethylolation procedures described below, the lignin is solubilized into an alkaline solution.
  • the amount of alkali used can vary depending on the type of lignin and the reaction conditions. For example, with ALCELL® lignin or low molecular weight ALCELL® lignin, from about 8% to about 20% caustic based on lignin solids can be used. The amount of water used was adjusted to obtain a solids content in the final admixture of from about 30% to about 45%.
  • the molecular weight of the lignin can be increased by crosslinking reactions. This can be accomplished by heating the lignin in alkaline solution for from about 1 to about 4 hours at from about 60°C to about 95°C.
  • An alternative crosslinking approach consists in taking lignin in alkaline solution and reacting it with an aldehyde. When formaldehyde is used, the reaction between the lignin and formaldehyde is a methylolation reaction.
  • the aldehyde can be added in a range of from about 0.3 to about 0.8 moles of aldehyde per lignin C-9 unit or of from about 5% to about 13; on a lignin weight basis.
  • the methylolation reaction can be carried out at from about 60°C to about 95°C for from about 1 to about 3 hours.
  • a sulfomethylolated lignin can be prepared in various alternative methods including the following.
  • the lignin can be reacted with a salt of hydroxymethane sulfonic acid such as its sodium salt.
  • the latter is also known as "adduct" and is available commercially. It is the addition product resulting from the reaction of formaldehyde with either sodium bisulfite or sodium sulfite.
  • the amount of adduct used for sulfomethylolation can be from about 8% to about 30% adduct solids based on a weight basis with the lignin and the sulfomethylolation reaction time is from about 2 to about 6 hours.
  • Sulfomethylolation is generally performed at from about 70°C to about 100°C.
  • the lignin can also be sulfomethylolated in a two-step process by initially reacting the lignin solution with excess of an aldehyde such as formaldehyde to methylolate the lignm thus introducing reactive aliphatic hydroxyl groups. This is done by following a similar procedure as described above to increase molecular weight but using higher levels of aldehyde such as, for example' of from about 10 to about 30% formaldehyde on lignm weight. This methylolation step is generally followed by reaction with from about 10 to about 25% sodium sulfite on a weight basis with lignm, at from about 120°C to about 160°C for from about 1 to about 4 hours.
  • an aldehyde such as formaldehyde
  • An alternative method to modify the molecular weight of the concrete admixtures of the present invention consists of crosslinking a sulfomethylolated product with a crosslinking agent such as epichlorohydrin.
  • the epichlorohydrin can be added in a range from about 0.05 to about 0.5 moles of epichlorohydrin per sulfomethylolated lignm C-9 unit or of from about 1.5 r to about 16.5% on a sulfomethylolated lignm weight basis.
  • the crosslinking reaction can be carried out at from about 60°C to about 100°C for from about 1 to about 4 hours.
  • the lignm-based admixtures can be mixed with a concrete mix in a range of from about 0.2% to about 1% on a weight basis with the cement in the concrete.
  • the admixture causes a water reduction of from about 5% to about 15% resulting in higher concrete strength and improved resistance to freeze and thaw.
  • An air detrainer such as tributyl phosphate, dibutyl phthalate, octyl alcohol, water-insoluble esters, carbonic and boric acids and silicones can be used.
  • Tributyl phosphate (TBP) can be added to the derivatized lignin in a range of from about 0.3% to about 5 ⁇ weight basis based on lignin solids resulting in a reduction in the air content of from about 9% to about 32% to as low as from about 2% to about 3% while maintaining reasonably high slump values.
  • the adduct can be prepared by addition of about 60 grams of 50% formaldehyde to a solution of about 126 grams sodium sulfite in about 700 milliliters of water.
  • a series of lignm-based admixtures were prepared by sulfomethylolation using as starting materials low molecular weight organosolv lignm, organosolv lignm and their methylolated counterparts.
  • the lignins were dissolved in an aqueous solution of sodium hydroxide containing the alkali levels specified in Table 1. The amount of water used was adjusted to obtain a solids content in the final admixture of approximately 35o by weight.
  • Those samples that were methylolated were treated with 0.5 moles of formaldehyde per lignm C-9 unit for 2 hours at 70°C.
  • the sulfomethylolation was carried out at a temperature of about 95°C and for 6 hours with adduct prepared as in Example I and using the levels described in Table 1.
  • the sulfomethylolated organosolv lignin-based admixtures were tested in cement slurries.
  • the mixes were prepared by mixing together the following ingredients:
  • Table 2 shows the initial set retardation on cement slurries. In general, the retardation decreases when the molecular weight increases and the level of adduct used decreases.
  • Sulfolmethylolated lignins were prepared using as startmg materials low molecular weight organosolv and organosolv lignm as outlined in Example II. The sulfomethylolation reaction took place at a temperature of about 95°C and for about 6 hours using the levels described in Table 4. The regular sulfomethylolated organosolv lignm was further crosslinked by reacting the sulfomethylolated lignm with 12.6 by weight of epichlorohydrin at about 95°C for 140 minutes. Upon cooling, the resultmg solution had a pH of 11.89, contained 41% solids by weight and had a viscosity of 3,600 cps. Table 4
  • Example IV The crosslinked sulfomethylolated lignins in Example IV were incorporated into cement slurries in the quantities set forth in Example III (with the exception of the fact that only 1,750 grams of water were used in this case) and the slurries were tested for torque decrease and set retardation. The results of those tests are provided in Table 5.
  • Table 6 demonstrates the beneficial plasticizing effect of the low molecular weight sulfomethylolated organosolv lignm of Example VI on concrete mixes as shown by the high slump numbers of such mixes relative to a concrete mix containing no admixture; see the first entry of Table 6.
  • the second entry of that table further reveals that if an air detrainer is not used, a high air content can be observed which causes a decrease in concrete strength.
  • Tributyl phosphate (TBP) can be added to reduce the air content while maintaining a high slump and high strength.
  • a low molecular weight lignin-based admixture prepared as in Example II with a 0.31 moles of adduct per lignin C-9 unit and an air-entrained reference mix were subjected to superplasticizing admixture qualification tests.
  • the admixture contained about 1.5% TBP as an air detrainer.
  • the reference mix was prepared without the superplasticizer admixture and included 147mL of air entraining agent per m " .
  • the following concrete mix proportions were used.
  • Standard CAN3-A266.6-M85 Fresh concrete was tested for workability by measuring the slump in accordance with ASTM specification C-143-90a. The time of setting was determined by measuring the penetration resistance on mortar extracted from the concrete mixture in accordance with ASTM specification C403- 92. The compressive strength of hardened concrete was measured in accordance with ASTM specification C-192-90a, ASTM specification C-39-86 and ASTM specification C-617-87. Length change was measured in accordance with CAN/CSA-A23.2-3C and CAN/CSA-A23.2-14A. Durability factor was calculated from relative dynamic modulus of elasticity changes in concrete prisms exposed to repeated cycles of freezing and thawing in accordance with ASTM specification C666-92.
  • Table 8 is a summary of the superplasticizing admixture qualification tests for the non-air-entrained and the air-entrained reference mix compositions. Table 8
  • admixtures formulated in accordance with the present invention can be classified as a superplasticizer.
  • Control 8 100 Control 15 100 Mix 1 8 115 Mix 2 15 98 Mix 3 15 107 Mix 4 15 108 Mix 5 15 118

Abstract

L'invention concerne un adjuvant permettant de diminuer la teneur en eau d'un mélange de béton. L'adjuvant comprend une solution alcaline d'une lignine sous forme sulfométhylolatée. La lignine sulfométhylolatée contenue dans l'adjuvant peut également être réticulée par un agent de réticulation. L'adjuvant comprend en outre un entraîneur d'air. L'invention concerne également des compositions de ciment originales contenant ledit adjuvant.
EP96938620A 1995-10-11 1996-10-11 Adjuvants du beton a base de lignine sulfomethylolatee Withdrawn EP0855995A4 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
WOPCT/US95/13836 1995-10-11
PCT/US1995/013836 WO1997013733A1 (fr) 1995-10-11 1995-10-11 Melanges pour betons a base de lignines
PCT/US1996/016232 WO1997013732A2 (fr) 1995-10-11 1996-10-11 Adjuvants du beton a base de lignine sulfomethylolatee

Publications (2)

Publication Number Publication Date
EP0855995A2 true EP0855995A2 (fr) 1998-08-05
EP0855995A4 EP0855995A4 (fr) 2000-01-12

Family

ID=22250050

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96938620A Withdrawn EP0855995A4 (fr) 1995-10-11 1996-10-11 Adjuvants du beton a base de lignine sulfomethylolatee

Country Status (6)

Country Link
EP (1) EP0855995A4 (fr)
JP (2) JPH11513358A (fr)
CN (1) CN1219921A (fr)
CA (2) CA2231641A1 (fr)
NO (2) NO981626L (fr)
WO (2) WO1997013733A1 (fr)

Cited By (1)

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CN111333358A (zh) * 2020-05-08 2020-06-26 中建西部建设西南有限公司 一种混凝土防冻剂及其制备方法和应用

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WO2001036344A2 (fr) * 1999-11-04 2001-05-25 Lignotech Usa, Inc. Dispersant a base de lignine assurant au beton une haute fluidite et un faible retard de prise
DE10313937A1 (de) 2003-03-27 2004-10-14 Wacker Polymer Systems Gmbh & Co. Kg Dispergiermittel
CN100400458C (zh) * 2005-01-04 2008-07-09 华南理工大学 木质素系地铁盾构注浆外加剂及其制备方法
CN101575418B (zh) * 2009-06-19 2011-06-22 华南理工大学 一种高磺化度高分子量木质素基高效减水剂及其制备方法
BR112012032999B1 (pt) 2010-06-26 2022-11-29 Virdia, Llc Hidrolisado lignocelulósico e métodos de hidrólise ácida e desacidificação para gerar misturas de açúcar a partir de lignocelulose
IL206678A0 (en) 2010-06-28 2010-12-30 Hcl Cleantech Ltd A method for the production of fermentable sugars
WO2012000773A1 (fr) 2010-06-29 2012-01-05 Construction Research & Technology Gmbh Couche de recouvrement semi-rigide
IL207329A0 (en) 2010-08-01 2010-12-30 Robert Jansen A method for refining a recycle extractant and for processing a lignocellulosic material and for the production of a carbohydrate composition
IL207945A0 (en) 2010-09-02 2010-12-30 Robert Jansen Method for the production of carbohydrates
PT106039A (pt) 2010-12-09 2012-10-26 Hcl Cleantech Ltd Processos e sistemas para o processamento de materiais lenhocelulósicos e composições relacionadas
US9512495B2 (en) 2011-04-07 2016-12-06 Virdia, Inc. Lignocellulose conversion processes and products
CN102627673A (zh) * 2012-03-23 2012-08-08 辽宁岩砂晶建材有限公司 木质素降解磺甲基化的方法

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US3689296A (en) * 1971-11-29 1972-09-05 Jean Guy Landry Cement composition containing alkanolaminolignosulfonate - formaldehyde setting retarder
US4764597A (en) * 1987-06-15 1988-08-16 Westvaco Corporation Method for methylolation of lignin materials

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US3689296A (en) * 1971-11-29 1972-09-05 Jean Guy Landry Cement composition containing alkanolaminolignosulfonate - formaldehyde setting retarder
US4764597A (en) * 1987-06-15 1988-08-16 Westvaco Corporation Method for methylolation of lignin materials

Non-Patent Citations (1)

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Title
See also references of WO9713732A2 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111333358A (zh) * 2020-05-08 2020-06-26 中建西部建设西南有限公司 一种混凝土防冻剂及其制备方法和应用

Also Published As

Publication number Publication date
WO1997013732A2 (fr) 1997-04-17
NO981626L (no) 1998-06-05
NO981625D0 (no) 1998-04-08
CN1219921A (zh) 1999-06-16
JPH11513653A (ja) 1999-11-24
EP0855995A4 (fr) 2000-01-12
JPH11513358A (ja) 1999-11-16
CA2231630A1 (fr) 1997-04-17
WO1997013733A1 (fr) 1997-04-17
NO981625L (no) 1998-06-05
NO981626D0 (no) 1998-04-08
WO1997013732A3 (fr) 1997-05-15
CA2231641A1 (fr) 1997-04-17

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