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  Porous carbonsUSPTO Application #: 20080090924Title: Porous carbons Abstract: A method is provided for making mesoporous resin. It comprises: (a) providing a nucleophilic component which comprises a phenolic compound or a phenol condensation prepolymer optionally with one or more modifying reagents selected from hydroquinone, resorcinol, urea, aromatic amines and heteroaromatic amines; (b) dissolving the nucleophilic component in a pore former selected from the group consisting of a diol, a diol ether, a cyclic ester, a substituted cyclic ester, a substituted linear amide, a substituted cyclic amide, an amino alcohol and a mixture of any of the above with water, together with at least one electrophilic cross-linking agent selected from the group consisting of formaldehyde, paraformaldehyde, furfural and hexamethylene tetramine; and (c) condensing the nucleophilic component and the electrophilic cross-linking agent in the presence of the pore former to form a porous resin. The resin may be formed in situ by pouring the partially cross-linked resin into hot oil. Mesoporous resin beads are obtained which can be carbonised into mesoporous carbon beads. (end of abstract) Agent: Bartlett & Sherer - New Freedom, PA, US Inventors: Stephen Robert Tennison, Oleksundr Prokopovych Kozynchenko, Volodymyr Vasyljovych Strelko, Andrew John Blackburn USPTO Applicaton #: 20080090924 - Class: 521180000 (USPTO) Related Patent Categories: Synthetic Resins Or Natural Rubbers -- Part Of The Class 520 Series, Synthetic Resins Or Natural Rubbers, Ion-exchange Polymer Or Process Of Preparing, Cellular Product Derived From A Phenol, Phenol Ether, Or Inorganic Phenolate Reactant The Patent Description & Claims data below is from USPTO Patent Application 20080090924. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional application of U.S. patent application Ser. No. 10/344,248 filed 29 May 2003 now pending, which was derived from International Application No. PCT/GB01/03560 filed 7 Aug. 2001. The entire disclosures of these earlier related applications are incorporated herein by reference. FIELD OF THE INVENTION [0002] The present invention relates to improved phenolic resin structures which can be used as ion exchange resins and can be used to prepare porous carbon materials and to a methods for making these. BACKGROUND TO THE INVENTION [0003] Sulphonated phenolic resins were first used as ion exchange resins in the 1930's (Adams et al, J Soc Chem Ind. 54, (1935) I-GT) and relatively stable cation and anion exchange resins were used extensively for the softening and demineralisation of water. Other phenolic based resins include the weak base anion exchange resins that have been primarily used in food processing applications (Cristal M J, Chem and Ind, 814, (1983) Nov. 7) and chelation resins which can be produced to give remarkable selectivity for the adsorption of metal ions such as cesium (U.S. Pat. No. 4,423,159, 1983 and U.S. 5,441,991, 1995). The ion exchange powders, can be produced by either bulk curing of the resin followed by milling (e.g. WO91/09891) to produce a low porosity powder or by reversed phase condensation (Unitaka Ltd U.S. Pat. No. 4,576,969 1986). One of the limitations of these materials was limited internal porosity and they were rapidly replaced by the highly porous sulphonated styrene divinyl benzene copolymer based ion exchange resins when these became available. However, although the phenolic based resins have largely disappeared, specific applications do still exist in food related industries based on their underlying performance characteristics. [0004] The phenolic resins can be carbonised to form mesoporous carbons. Mesoporous carbons are used as adsorbents or catalysts supports and can be used in spherical, granular of thin film form. Existing production methods use gas phase and chemical activation routes to produce mesoporous carbons but, activated carbon, as conventionally produced, is normally microporous (<2 nm pore diameter--IUPAC definition) with little or no pore volume in the mesopore (2-50 nm) and macropore (>50 nm) range. For some critical adsorption processes such as evaporative emission control, and when used as a catalyst support, particularly in liquid phase applications, this is a major drawback. [0005] Conventional activated carbons can be made mesoporous through severe activation but this seriously degrades their mechanical properties and the materials are generally then only available as fine powders. U.S. Pat. No. 4,677,086 discloses the use of chemical activation to produce mesoporous carbons without such severe mechanical degradation and which also can be produced as extrudates. These are however still produced as powders and must then be bound to produce, for instance, extrudate for use in fixed bed gas phase processes. In most cases the binders that can be used are polymeric or ceramic which then restricts the conditions under which the carbons can be used. [0006] Chemical activation can also be used to directly produce mesoporous carbons by pelleting or extruding a plasticised acidic lignin base char and then directly carbonising and activating the mixture as disclosed in U.S. Pat. No. 5,324,703. The production route also leads to a low macroporosity, which can have disadvantages in catalytic and liquid phase processes. The route also has the disadvantage of requiring compounds such as phosphoric acid and zinc chloride as the activating agents, which can cause severe environmental problems and have a major impact on the materials of construction of the process plant. [0007] An alternative route is to carbonise sulphonated styrene--divinylbenzene co-polymers as disclosed in U.S. Pat. No. 4,040,990 and U.S. Pat. No. 4,839,331. These produce carbons directly by pyrolysis with meso/microporosity without recourse to further activation. The materials therefore have good mechanical properties. They are, however, limited to relatively small particle sizes, fixed by the polymer production route, and have a limited range of mesopore structures. They are also very expensive reflecting the high cost of the precursor polymer, the low carbon yields and environmental problems associated with processing polymers containing large amounts of sulphur. The resultant carbons are also contaminated with sulphur, which restricts their use as catalysts supports. [0008] A further route has also been disclosed in U.S. Pat. No. 5,977,016 whereby sulphonated styrene--divinylbenzene co-polymer particles can be formed into pellets in the presence of large volume of concentrated sulphuric acid and then carbonised to give structured materials with both meso- and macroporosity. The route is however complex and expensive with significant environmental problems [0009] A further route is disclosed in U.S. Pat. No. 4,263,268 where a mesoporous silica with the desired macroshape (i.e. spheres) is impregnated with a carbon forming polymer, such as phenolic or polyfurfuryl resin and then dissolving the silica template in an alkali. This again is a highly expensive route and is only capable of producing the carbon material in a limited range of shapes and forms SUMMARY OF THE INVENTION [0010] We have now devised an improved method of producing porous resin structures which can be used to form porous carbons such as mesoporous carbon without, gas phase or chemical activation. [0011] According to the invention there is provided a method for forming a porous resin structure which method comprises the condensation of a nucleophilic component with an electrophilic cross-linking agents in solution in the presence of a pore former. [0012] The condensation can be catalysed or non catalysed. [0013] The invention also provides a method for forming a porous carbon structure in which the porous resin is carbonised to form the porous carbon structure. BRIEF DESCRIPTION OF THE DRAWINGS [0014] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: [0015] FIG. 1 shows pore former content in the resin composition on the porosity of derived carbonized material with reaction system Phenol- Formaldehyde- Ethylene Glycol-Sulphuric Acid; [0016] FIG. 2 shows the effect of aniline content in resin composition of the reaction system Phenol-Aniline-Formaldehyde-Ethylene Glycol-Suphuric Acid on the porosity of derived carbons; [0017] FIG. 3a shows the effect of the pore former content on the porosity of phenolic resins with reaction system Novolac-Hexamine-Ethylene Glycol; [0018] FIG. 3b shows the effect the effect of the pore former in resin composition on the porosity of corresponding carbonized materials with reaction system Novolac-Hexamine-Ethylene Glycol; [0019] FIG. 4 shows the effect of additions of Aniline or Urea to the resin compositions of Novolac-Hexamine-Ethylene Glycol reaction system on the porosity of resulting carbons; Continue reading... Full patent description for Porous carbons Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Porous carbons patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Porous carbons or other areas of interest. ### Previous Patent Application: Container, methods and components involving multi-use bio-based materials Next Patent Application: Color forming compositions Industry Class: Synthetic resins or natural rubbers -- part of the class 520 series ### FreshPatents.com Support Thank you for viewing the Porous carbons patent info. 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