WO1994000382A1 - Charbon actif ameliore par le traitement des lignites au moyen d'hydroxyde ou sels de potassium et/ou de sodium et destine a l'adsorption - Google Patents

Charbon actif ameliore par le traitement des lignites au moyen d'hydroxyde ou sels de potassium et/ou de sodium et destine a l'adsorption Download PDF

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Publication number
WO1994000382A1
WO1994000382A1 PCT/US1993/005804 US9305804W WO9400382A1 WO 1994000382 A1 WO1994000382 A1 WO 1994000382A1 US 9305804 W US9305804 W US 9305804W WO 9400382 A1 WO9400382 A1 WO 9400382A1
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WO
WIPO (PCT)
Prior art keywords
activated carbon
set forth
lignite
potassium
brown coal
Prior art date
Application number
PCT/US1993/005804
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English (en)
Inventor
Toan P. Vo
Original Assignee
Calgon Carbon Corporation
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 Calgon Carbon Corporation filed Critical Calgon Carbon Corporation
Priority to CA002138376A priority Critical patent/CA2138376A1/fr
Priority to JP6502455A priority patent/JPH07508215A/ja
Publication of WO1994000382A1 publication Critical patent/WO1994000382A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/30—Active carbon
    • C01B32/312—Preparation
    • C01B32/342—Preparation characterised by non-gaseous activating agents

Definitions

  • the present invention relates to improved activated carbon for adsorption of organic vapors, gases or vapors, using potassium and sodium hydroxide or potassium and sodium salts so as to achieve an activated carbon with increased working capacity, lower apparent density and increased capacity for the removal of gases, vapors and liquids.
  • the present invention ⁇ involves the manufacture of activated carbons from inexpensive lignite (brown coal) to achieve superior adsorptive working capacity and other desirable attributes in the improved adsorptive material.
  • activated carbons are useful in removing, adsorbing or storing organic gases, vapors and liquids; specific uses include, but are not limited to, evaporative loss control canisters on automobiles, in-line filters, solvent recovery filters and other applications.
  • evaporative loss control canisters on automobiles
  • solvent recovery filters and other applications.
  • the activated carbon should have the highest possible hydrocarbon working capacity and the lowest possible apparent density.
  • SUBSTITUTE SHEET formulations that include the use of potassium impregnation before activation for these purposes are known; however, known formulations lack desirable (working) adsorptive capacity, may require the use of more adsorptive material than is desirable in many applications, and/or may be expensive to produce. In the case of carbon filters or beds to be used in evaporative control devices in vehicular fuel systems, the drawbacks associated with such known fuel vapor control carbons can be significant.
  • the activated carbons of the present invention may also involve the further use of special impregnants to remove gases, vapors and liquids that would not otherwise be removed through the use of unimpregnated activated carbons.
  • the present invention results in activated carbons having an improved and unique pore structure which yields superior working capacity resulting in a more effective carbon that results in cost, weight and space savings.
  • lignite lower cost feed stock
  • the present invention is intended to provide a more effective, more compact, and less expensive activated carbon that is effective in removing and/or storing gases and/or vapors, and liquids for use in automotive and industrial applications.
  • the potassium and/or sodium hydroxides and salts thereof used for the treatment of the lignites (brown coals) of the present invention are applied prior to charring and activation in an efficient, reliable and cost-effective manner.
  • the present invention comprises an activated carbon manufactured from lignite (brown coal) by impregnating a lignite with a solution of potassium and/or sodium hydroxide or salt thereof followed by charring and thereafter activation.
  • lignite brown coal
  • the terms "lignite” and "brown coal” are low-rank coals having an oxygen content greater than from about 15 to 17% up to about 30%.
  • the present invention solves the problem of the required use of more expensive carbons, as it achieves improved performance by using
  • the carbons of the present invention attain greater hydrocarbon working capacities, lower apparent densities and increased hydrocarbon capacities.
  • the activated carbons of the present invention have improved and unique pore structures, which yield superior working capacities; these carbons yield cost savings, environmental benefits and superior performance.
  • the carbons of the present invention can be significantly less expensive to produce, and have greater working capacities than known carbons produced from known KOH impregnated carbonaceous materials, to include known steam activated wood-based pellet carbons, or brown coals and pit-wet lignites impregnated with KOH before activation.
  • One commercial wood-base carbon was found to have a gasoline working capacity of 34 g/1.
  • a brown coal carbon was found to have a gasoline working capacity of 29.4 g/1.
  • the carbon present invention can achieve gasoline working capacities greater than 57.0 g/1.
  • the activated carbons of present invention can therefore achieve an increase in working capacity of at least 91% over the aforementioned ' brown coal carbon and at least 67% over the aforementioned wood-base carbon.
  • the wood-based carbon is a more expensive material and is less effective than the lignite (brown coal) based carbons of the present invention.
  • the known brown coal or pit-wet lignite substitute on the other hand, is "heavy" to ship due to its high water content and produces less effective activated carbon.
  • the activated carbons of the present invention also avoid unnecessary excess weight of pit-wet material, and provides for processing equipment advantages.
  • the product of the present invention may be granulated, pelletized or "shaped" into other forms without a binder via (most desirably) pressure formation, or prepared with a binder.
  • the process of the present invention is effective in an expanded range of carbonaceous material compositions, treated prior to charring and activation with potassium or sodium.
  • the amount (by weight) of potassium or sodium hydroxide or salts thereof present on the carbon after charring and activation can increase, for example double, due to carbon shrinkage following activation.
  • the formulations may be varied, depending on the particular application and/or performance characteristics desired.
  • preferred embodiments of the present invention comprise a low-rank coal, preferably a lignite, treated prior to charring and activation to provide a composition containing, by weight, up to about 30% potassium (as KOH or an equivalent potassium salt). Up tc about 120% water may also be used.
  • This potassium or sodium hydroxide or salt thereof can be effectively dispersed over agglomerated lignite granules (8x30, 6x20, 12x30, and other mesh sizes), or any similar carbonaceous media.
  • the apparent density of the carbons of the present invention are desirably less than 370 g/1, and have a high hexane working capacity (defined hereinafter) of at least 5.4%.
  • SUBSTITUTE SHEET A specific preferred embodiment of the present invention comprises lignite (brown coal) treated with about 5% potassium (KOH) and 25% water prior to charring and activation.
  • the activated carbons of the present invention have a wide-range of utility and provide balanced performance. For certain applications, such as in automotive applications, the activated carbons provide high working capacities which can be regenerated by passage of ambient air over the carbon. Other advantages of the activated carbons of the present invention will become apparent from a perusal of the following detailed description of presently preferred embodiments taken in connection with the accompanying drawings.
  • Figure 1 is a flow diagram of the process of the present invention for manufacturing pelletized activated carbon
  • Figure 2 is a flow diagram of the process of the present invention for manufacturing a nonagglomerated granular activated carbon
  • Figure 3 is a flow diagram of the process of the present invention for manufacturing an agglomerated granular activated carbon.
  • the present invention is directed to the manufacture of activated carbons from lignites (brown
  • SUBSTITUTE SHEET coals having increased surface area and superior working capacities for the adsorption of hydrocarbons and other gases, vapors and liquids.
  • Activated carbons prepared according to the present invention are superior adsorbents for evaporative loss control canisters, solvent recovery and other applications.
  • the process of the present invention is effective in using a broad range of potassium or sodium hydroxides and/or salts thereof treatment compositions. These formulations may be varied, depending on the particular application and/or performance characteristics desired for the activated carbon.
  • a number of process parameters have been found to affect the performance of the carbon product. These parameters include: (1) the particular potassium or sodium hydroxide or salt used, the level of these hydroxides and salts, and the source from which these hydroxides or salts are obtained; (2) the method of hydroxide and salt treatment of the lignite (brown coal); (3) the process used to char the lignite (brown coal); (4) the process used to activate the carbon; (5) the procedure used to dry and/or wash the activated carbon; (6) the amount of moisture present or added at each step; and (7) the activity of the starting lignite (brown coal). Other parameters also affect the final characteristics of the activated carbon of the present invention, but to a lesser extent.
  • Initial preparation comprises pulverizing the dry lignite (brown coal) and then treating it with a solution of KOH and, thereafter, forming it into two-millimeter pellets.
  • This procedure maximizes the advantages of the potential interaction between KOH and oxygenated surface groups of lignite (brown coal) for the present invention.
  • These pellets were charred in an inert atmosphere and activated in steam. This preferred method of treating the lignite with KOH prior to charring yielded surprisingly desirable results.
  • Hexane capacity and working capacity of pellets that were activated in the range of 870-900°C reached approximately 42-45% and 13-14%, respectively.
  • Butane capacity and working capacity reached approximately 36-46% and 22-24%, respectively.
  • KOH loading of 5.2% in the char feedstock produced the activated product with hexane capacity reaching approximately 45% at activation temperatures of 870-900°C.
  • the hexane working capacity of these products reached approximately 13-14%.
  • the hexane capacity and hexane working capacity are approximately 32% and 17%, respectively for a first commercially used carbon and 44% and 20%, respectively for a second commercially used carbon) .
  • the activated carbon of the present invention using lignites has an apparent density as low
  • Methods of preparation may include one, two or more treatment cycles with the selected hydroxide or salt(s) by spraying, wetting or other process.
  • the constituents should preferably be applied to the lignite (brown coal) using a single application.
  • the resulting mixture may thereafter be, as desired or necessary, thermally processed by charring and steam activation into the desired activated carbon product.
  • a method involving a second application can also be used to achieve the desired hydroxide or salt loadings.
  • This two-step application can also be used to achieve uniform high hydroxide or salt loadings, or application of different liquids than those applied during the first loading.
  • Formulations containing various loadings of potassium or sodium hydroxide or salts thereof on granular, pelletized, and other shaped carbonaceous particles of differing mesh sizes will likewise desirably perform.
  • Low-moisture content e.g. , less than 20% by weight
  • lignite brown coal
  • Prior art sample 1 a wood-char-based pellet impregnated with KOH, steam activated
  • Prior art sample 2 Karl Fischer
  • present invention sample 1 activated carbon has a gasoline working capacity of 49.7 g/1.
  • present invention sample 1 achieves an increase in gasoline working capacity of at least 69% over prior art sample 1 and at least 46% over prior art sample 2.
  • the favorable results achieved with the present invention sample 2 activated carbon are even more remarkable, demonstrating an increase in working capacity of at least 91% over prior art sample 2 and at least 67% over prior art sample 1.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Carbon And Carbon Compounds (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

L'invention se rapporte à des charbons actifs destinés à l'adsorption de vapeurs, de gaz et de liquides dans une variété d'applications et qui sont préparés à partir d'une lignite sèche ou charbon brun traités avec au moins un hydroxyde et/ou des sels de potassium et/ou de sodium qui sont carbonisés et ensuite activés. Ces charbons actifs possèdent des capacités de travail d'hexane accrue d'au moins 5,4 %.
PCT/US1993/005804 1992-06-19 1993-06-17 Charbon actif ameliore par le traitement des lignites au moyen d'hydroxyde ou sels de potassium et/ou de sodium et destine a l'adsorption WO1994000382A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CA002138376A CA2138376A1 (fr) 1992-06-19 1993-06-17 Charbon active par le traitement de lignites avec de l'hydroxyde de potassium et (ou) de sodium ou des sels et leur adsorption
JP6502455A JPH07508215A (ja) 1992-06-19 1993-06-17 水酸化カリウムおよび／または水酸化ナトリウムまたはその塩で亜炭を処理することによる活性炭およびそれによる吸着

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US90135892A 1992-06-19 1992-06-19
US07/901,358 1992-06-19

Publications (1)

Publication Number Publication Date
WO1994000382A1 true WO1994000382A1 (fr) 1994-01-06

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Application Number Title Priority Date Filing Date
PCT/US1993/005804 WO1994000382A1 (fr) 1992-06-19 1993-06-17 Charbon actif ameliore par le traitement des lignites au moyen d'hydroxyde ou sels de potassium et/ou de sodium et destine a l'adsorption

Country Status (3)

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JP (1) JPH07508215A (fr)
CA (1) CA2138376A1 (fr)
WO (1) WO1994000382A1 (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2176120A1 (es) * 2001-04-17 2002-11-16 Universidasd De Alicante Procedimiento para la obtencion de carbones activados mediante activacion quimica con hidroxido sodico, hidroxido potasico o sus mezclas.
ES2176121A1 (es) * 2001-04-17 2002-11-16 Univ Alicante Procedimiento para la obtencion de carbones activados mediante mezcla fisica de precursores carbonosos con hidroxido sodico, hidroxido potasico o sus mezclas.
RU2449948C1 (ru) * 2010-10-29 2012-05-10 Российская Федерация, от имени которой выступает Министерство промышленности и торговли Российской Федерации (Минпромторг России) Способ получения активного угля
KR20120083909A (ko) * 2009-10-15 2012-07-26 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
WO2014099422A1 (fr) * 2012-12-18 2014-06-26 Cabot Corporation Élimination de siloxanes contenus dans des gaz à l'aide de charbons actifs améliorés à base de lignite et milieu adsorbant utilisé à cette fin
CN105664892A (zh) * 2016-01-20 2016-06-15 昆明理工大学 利用褐煤与黄磷水淬渣制备砷吸附材料的方法
CN113233462A (zh) * 2021-03-15 2021-08-10 河南省冶金研究所有限责任公司 一种高比表面积褐煤基活性炭的制备方法
CN113880083A (zh) * 2021-10-27 2022-01-04 中冶集团武汉勘察研究院有限公司 一种利用丝瓜络制备生物质活性炭的方法
US11603315B2 (en) * 2019-12-09 2023-03-14 Carbonxt, Inc. Water-resistant and high strength carbon products

Citations (7)

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Publication number Priority date Publication date Assignee Title
US3492244A (en) * 1965-10-13 1970-01-27 Takeda Chemical Industries Ltd Method for the production of coke
US3544263A (en) * 1967-01-13 1970-12-01 Takeda Chemical Industries Ltd Method of removing sulfur dioxide from gases
US3764561A (en) * 1971-03-09 1973-10-09 Takeda Chemical Industries Ltd Activated carbon from admixture of coking coal and inorganic potassium salts
DE2230527A1 (de) * 1972-06-22 1974-01-10 Bosch Gmbh Robert Geblaese mit einem elektromotor und einem von diesem angetriebenen luefterrad
US4039473A (en) * 1975-03-18 1977-08-02 Commonwealth Scientific And Industrial Research Organization Active carbon by potassium ion exchange and leaching of carbonaceous material
DD227946A1 (de) * 1984-07-03 1985-10-02 Freiberg Bergakademie Verfahren zur herstellung abriebfester, koerniger aktivkohle
US4769359A (en) * 1985-09-24 1988-09-06 The British Petroleum Company P.L.C. Process for the production of adsorbent carbon

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3492244A (en) * 1965-10-13 1970-01-27 Takeda Chemical Industries Ltd Method for the production of coke
US3544263A (en) * 1967-01-13 1970-12-01 Takeda Chemical Industries Ltd Method of removing sulfur dioxide from gases
US3764561A (en) * 1971-03-09 1973-10-09 Takeda Chemical Industries Ltd Activated carbon from admixture of coking coal and inorganic potassium salts
DE2230527A1 (de) * 1972-06-22 1974-01-10 Bosch Gmbh Robert Geblaese mit einem elektromotor und einem von diesem angetriebenen luefterrad
US4039473A (en) * 1975-03-18 1977-08-02 Commonwealth Scientific And Industrial Research Organization Active carbon by potassium ion exchange and leaching of carbonaceous material
DD227946A1 (de) * 1984-07-03 1985-10-02 Freiberg Bergakademie Verfahren zur herstellung abriebfester, koerniger aktivkohle
US4769359A (en) * 1985-09-24 1988-09-06 The British Petroleum Company P.L.C. Process for the production of adsorbent carbon

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2176120A1 (es) * 2001-04-17 2002-11-16 Universidasd De Alicante Procedimiento para la obtencion de carbones activados mediante activacion quimica con hidroxido sodico, hidroxido potasico o sus mezclas.
ES2176121A1 (es) * 2001-04-17 2002-11-16 Univ Alicante Procedimiento para la obtencion de carbones activados mediante mezcla fisica de precursores carbonosos con hidroxido sodico, hidroxido potasico o sus mezclas.
KR20160005796A (ko) * 2009-10-15 2016-01-15 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
US9309176B2 (en) 2009-10-15 2016-04-12 Mexichem Amanco Holding S.A. De C.V. Process for purifying (hydro)fluoroalkenes
US20120203037A1 (en) * 2009-10-15 2012-08-09 Mexichem Amanco Holding S.A. De C.V. Process for purifying (hydro) fluoroalkenes
CN102695692A (zh) * 2009-10-15 2012-09-26 墨西哥化学阿玛科股份有限公司 用于纯化（氢）氟烯烃的方法
KR101827917B1 (ko) * 2009-10-15 2018-02-09 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
CN102695692B (zh) * 2009-10-15 2015-02-25 墨西哥化学阿玛科股份有限公司 用于纯化(氢)氟烯烃的方法
US9012703B2 (en) 2009-10-15 2015-04-21 Mexichem Amanco Holdings S.A. De C.V. Process for purifying (hydro) fluoroalkenes
US9790152B2 (en) 2009-10-15 2017-10-17 Mexichem Amanco Holding S.A. De C.V. Process for purifying (hydro)fluoroalkenes
US9624148B2 (en) 2009-10-15 2017-04-18 Mexichem Amanco Holding S.A. De C.V. Process for purifying (hydro)fluoroalkenes
KR20120083909A (ko) * 2009-10-15 2012-07-26 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
KR101721598B1 (ko) * 2009-10-15 2017-03-30 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
KR101698073B1 (ko) * 2009-10-15 2017-01-19 멕시켐 아만코 홀딩 에스.에이. 데 씨.브이. (하이드로)플루오로알켄 정제 방법
RU2449948C1 (ru) * 2010-10-29 2012-05-10 Российская Федерация, от имени которой выступает Министерство промышленности и торговли Российской Федерации (Минпромторг России) Способ получения активного угля
US9023755B2 (en) 2012-12-18 2015-05-05 Cabot Corporation Siloxane removal from gases using lignite-enhanced activated carbons and adsorbent media used therefor
WO2014099422A1 (fr) * 2012-12-18 2014-06-26 Cabot Corporation Élimination de siloxanes contenus dans des gaz à l'aide de charbons actifs améliorés à base de lignite et milieu adsorbant utilisé à cette fin
CN105664892A (zh) * 2016-01-20 2016-06-15 昆明理工大学 利用褐煤与黄磷水淬渣制备砷吸附材料的方法
US11603315B2 (en) * 2019-12-09 2023-03-14 Carbonxt, Inc. Water-resistant and high strength carbon products
CN113233462A (zh) * 2021-03-15 2021-08-10 河南省冶金研究所有限责任公司 一种高比表面积褐煤基活性炭的制备方法
CN113880083A (zh) * 2021-10-27 2022-01-04 中冶集团武汉勘察研究院有限公司 一种利用丝瓜络制备生物质活性炭的方法
CN113880083B (zh) * 2021-10-27 2023-06-16 中冶集团武汉勘察研究院有限公司 一种利用丝瓜络制备生物质活性炭的方法

Also Published As

Publication number Publication date
CA2138376A1 (fr) 1994-01-06
JPH07508215A (ja) 1995-09-14

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