200418558 Π) 玖、發明說明 【發明所屬之技術領域】 本發明係有關於一種製備多孔纖維素體的方法，一種 多孔纖維素體及其用途’以及一種熱解該纖維素體而得到 之多孔碳體及其用途。 本發明之多孔體即所謂的氣凝膠。 【先前技術】 依據第六版工業化學Ullmann百科全書之2002年電 子版，氣凝膠是一種具有極低密度的高孔隙度固體。在更 精確的定義中，氣凝膠是一種當凝膠的孔隙流體被空氣取 代時’其孔隙及網絡結構仍可保持完全或絕大部份完整的 材料。 凝膠是由似海棉的三維網絡所組成，其孔隙充滿流 體。相對於在乾燥期間網絡結構仍可維持實質不變的氣凝 膠’凝膠可利用習用的乾燥方法（提高溫度及/或降低壓力） 而得到稱爲乾凝膠（xero gels)的高度縮皺體。凝膠的縮皺 是由於孔隙流體蒸發時在流體-蒸汽的界面受到毛細力所 致。 如何乾燥凝膠的方法因此是製造高孔隙度氣凝膠的決 定步驟。其可利用下列技術： -超臨界乾燥 -在宥機溶劑中 -在二氧化碳中（於下文中，『超臨界溶劑』一詞同 -6 - (2) (2)200418558 時使用於超臨界有機溶劑及超臨界二氧化碳） -冷凍乾燥 -在常壓下乾燥，然而此法僅可能用於極其穩定之網 絡結構。 氣凝膠特定的光、熱、聲和機械性質是固體基質與奈 米範圍內的空氣塡充孔隙的結合結果。 主要的工業生產氣凝膠產品具有無機性質，並由矽酸 與金屬氧化物所組成。然而有機氣凝膠亦爲習知者（例如 美國能源部之US 4 873 218)。 對於纖維素，高孔隙度的模製體已爲習知，但是在專 利文獻中很少例外地只述及濕式狀態的製造，在那些案例 中並未涉及氣凝膠。 大體上，係由經水解的黃原酸纖維素溶液或乙酸纖維 素起始。 依據US 4,05 5,5 10的黏膠方法，該製備步驟爲： -黏膠（在已稀釋苛性鈉中的黃原酸纖維素溶液）被分 散在不與水溶混的有機溶劑，例如氯苯’ -已分散的黏膠藉由熱引致的溶膠-凝膠-交換（加熱該 混合物至90°C )而固化， -分離出纖維素珠粒’ -在水性介質中再生成酸’及 _淸洗。 因此得到之纖維素體具有9 0 %之孔隙度（水的體積含 量）。其中的水（參見·· J· Stamberg 等人，Acta Polymerica (3) (3)200418558 30( 1 979) 12輯，734- 73 9)可被很多不同種類的有機溶劑取 代，而且如此做幾乎不改變孔隙度程度。 乾燥之後，得到數値爲〇 %至70 %孔隙度的產品’但 係依據乾燥之前纖維素最後是與何種溶劑作用而定。然 而，由此可得到的結論是即使在最謹慎的乾燥條件下’對 孔隙度仍會產生相當的損失。 對經乾燥纖維素體的最高孔隙度數値，本案申請人目 前所知者爲 83.6%，該數値揭示於 Peska等人，Cd Chem. Techn. 21(1978) pp. 419-428 。 製備纖維素體的進一步實例述於： •Stamberg，J.，『珠粒纖維素』，分離及純化方法 17(2) (1988) 155-183 •US 2,543,928 •DE 1，792,230，相對應案 US 3,5 97,350 •DE 1 18,887，相對應案 US 4,055,5 10 •GB 1,575,700 •US 4,312,980 •US 4,946,953 •WO 91/00142 •WO 9 1/09878，相對應案 US 5,5 27,902 •US 5,328,603 •EP 850,979 D D 1 1 8，8 8 7所包含之敘述爲僅含有低於3 0 %的低孔 隙體積纖維素珠粒是屬於尺寸穩定並可乾燥而無需任何特 -8- (4) (4)200418558 別措施來維持孔隙度。 在 GB 1，5 75,700中，將可水解纖維素衍生物，例如 乙酸纖維素，溶解於水可溶混有機溶劑中，溶液被分散成 爲小液滴並導入沈澱浴（例如水），分離出珠粒並淸洗，纖 維素衍生物因此水解爲纖維素，及再次淸洗。因此得到濕 式產物，其所使用如實施例1中所述地以超臨界二氧化碳 的乾燥可獨特地用於藉助電子顯微鏡鑑定的製備方法。 熟於此藝者所習知的諸多方法均伴隨著與生態問題有 關的缺點，例如使用氯化的有機溶劑、在膠黏方法期間釋 出有毒的硫化合物、及纖維素需使用含銅溶劑。至目前爲 止，使用替代性纖維素溶劑，例如二甲基乙醯胺和氯化鋰 組合，的製備方法仍無法提供証據足以適用於工業的溶劑 回收。 由黏膠或由氫氧化鈉起始的方法由於低聚合度纖維素 的溶解作用而受到限制。 除了簡述至目前爲止用來製備纖維素珠粒的方法， WO 99/3 1141亦揭示包含下列步驟之方法： -製備纖維素溶液（聚合度150至2000，纖維素濃度 0.5至25重量％ )， -細微分散纖維素溶液與具有與溶液不溶混分散劑的 分散液， -溶液粒子的固化，其係利用a)將分散液冷卻至低於 纖維素溶液的熔融溫度，並分離分散劑與固化粒子，或b) 利用與分散劑易溶混的沈澱劑進行粒子的沈澱， -9 - (5) 200418558 -由流體中分離出珠粒。 爲了製造具有粒度範圍由50微米至1000微米的粒 子，可將溶液置入具有半徑範圍由40微米至1000微米的 噴射器進行成形，該噴射器可藉助於旋轉切割板而分隔成 數區段。200418558 Π) 发明 Description of the invention [Technical field to which the invention belongs] The present invention relates to a method for preparing a porous cellulose body, a porous cellulose body and uses thereof, and a porous carbon obtained by pyrolyzing the cellulose body Body and its uses. The porous body of the present invention is a so-called aerogel. [Prior art] According to the 2002 electronic edition of the sixth edition of the Ullmann Encyclopedia of Industrial Chemistry, an aerogel is a highly porous solid with extremely low density. In a more precise definition, an aerogel is a material whose pores and network structure can remain completely or mostly intact when the gel's pore fluid is replaced by air. The gel is composed of a three-dimensional network like sponge, and its pores are filled with fluid. Compared to aerogels that maintain a substantially constant network structure during drying, gels can be highly wrinkled, called xero gels, using conventional drying methods (elevating temperature and / or reducing pressure). body. Gel wrinkling is caused by capillary forces at the fluid-vapor interface when the pore fluid evaporates. The method of how to dry the gel is therefore a decisive step in making a high porosity aerogel. It can use the following techniques:-Supercritical drying-in organic solvents-in carbon dioxide (hereinafter, the term "supercritical solvent" is the same as -6-(2) (2) 200418558 when used in supercritical organic solvents And supercritical carbon dioxide)-freeze-drying-drying at atmospheric pressure, however this method is only possible for extremely stable network structures. The specific optical, thermal, acoustic and mechanical properties of aerogels are the result of the combination of a solid matrix with air-filled pores in the nanometer range. The main industrially produced aerogel products are inorganic in nature and consist of silicic acid and metal oxides. However, organic aerogels are also known (eg US Department of Energy US 4 873 218). For cellulose, high-porosity molded bodies are well known, but few exceptions in the patent literature only refer to wet-state manufacturing, and aerogels are not involved in those cases. In general, it starts with a solution of hydrolyzed cellulose xanthate or cellulose acetate. According to the viscose method of US 4,05 5,5 10, the preparation steps are:-the viscose (a solution of xanthan cellulose in diluted caustic soda) is dispersed in an organic solvent that is not miscible with water, such as chlorine Benzene '-the dispersed viscose is cured by heat-induced sol-gel-exchange (heating the mixture to 90 ° C),-the cellulose beads are separated--the acid is regenerated in an aqueous medium and _ Wash. The cellulose body thus obtained had a porosity (volume content of water) of 90%. The water in it (see J. Stamberg et al., Acta Polymerica (3) (3) 200418558 30 (1 979) 12th edition, 734-73 9) can be replaced by many different kinds of organic solvents, and it is almost impossible to do so Change the degree of porosity. After drying, a product with a porosity of 0% to 70% is obtained, but it depends on what kind of solvent the cellulose has finally reacted with before drying. However, the conclusion that can be drawn from this is that even under the most cautious drying conditions, a considerable loss of porosity will still occur. The highest porosity number 经 of the dried cellulose body is 83.6% known to the applicant of the present case, and this number is disclosed in Peska et al., Cd Chem. Techn. 21 (1978) pp. 419-428. Further examples of the preparation of cellulose bodies are described in: • Stamberg, J., “Bead Cellulose”, Method of Separation and Purification 17 (2) (1988) 155-183 • US 2,543,928 • DE 1,792,230, corresponding US 3,5 97,350 • DE 1 18,887, corresponding US 4,055,5 10 • GB 1,575,700 • US 4,312,980 • US 4,946,953 • WO 91/00142 • WO 9 1/09878, corresponding US 5,5 27,902 • US 5,328,603 • EP 850,979 DD 1 1 8, 8 8 7 contains a description that contains less than 30% of low pore volume cellulose beads that are dimensionally stable and dry without any special requirements. 8- (4) (4) 200418558 Other measures to maintain porosity. In GB 1,5 75,700, a hydrolyzable cellulose derivative, such as cellulose acetate, is dissolved in a water-miscible organic solvent, and the solution is dispersed into small droplets and introduced into a precipitation bath (such as water) to separate the beads. The granules were washed and washed, the cellulose derivative was hydrolyzed to cellulose, and washed again. Thus, a wet product was obtained, which was dried using supercritical carbon dioxide as described in Example 1, and could be used uniquely for the preparation method identified by means of an electron microscope. Many methods known to the artist are accompanied by ecological issues, such as the use of chlorinated organic solvents, the release of toxic sulfur compounds during the gluing process, and the use of copper-containing solvents for cellulose. To date, preparation methods using alternative cellulose solvents, such as a combination of dimethylacetamide and lithium chloride, have not provided evidence sufficient for industrial solvent recovery. Processes starting from viscose or from sodium hydroxide are limited due to the dissolution of low-polymerization cellulose. In addition to briefly describing the method used to prepare cellulose beads so far, WO 99/3 1141 also discloses a method comprising the following steps:-preparing a cellulose solution (degree of polymerization 150 to 2000, cellulose concentration 0.5 to 25% by weight) -Micro-dispersed cellulose solution and dispersion with immiscible dispersant,-Solidification of solution particles, which uses a) to cool the dispersion to below the melting temperature of the cellulose solution, and separate the dispersant from solidification Particles, or b) Precipitation of particles using a precipitant that is miscible with the dispersant. -9-(5) 200418558-Separation of beads from the fluid. In order to produce particles with a particle size ranging from 50 to 1000 microns, the solution can be shaped by placing it in an ejector with a radius ranging from 40 to 1000 microns, which can be divided into sections by rotating a cutting plate.
所得到之濕式狀態粒子具有孔隙體積5 %至95 %。纖 維素珠粒進行乾燥的可能性於其中提及，但在 WO 9 9/3 1141中缺乏進一步例証因此猜測僅形成低孔隙度產 物。在實施例中，纖維素所使用的溶劑爲N -甲基-嗎啉-N -氧化物（NMMO)。 製備多孔纖維素珠粒的進一步方法揭示於 WO 0 2/05 73 19。在此文獻中同樣地未含有所生成纖維素珠粒 可能進行乾燥的進一步詳情。The obtained wet-state particles have a pore volume of 5% to 95%. The possibility of drying the cellulose beads is mentioned therein, but further examples are lacking in WO 9 9/3 1141 so it is speculated that only low porosity products are formed. In the examples, the solvent used for cellulose is N-methyl-morpholine-N-oxide (NMMO). A further method for preparing porous cellulose beads is disclosed in WO 0 2/05 73 19. This document likewise does not contain further details on the possible drying of the resulting cellulose beads.
在一個實施例（實施例2)中，得到具有平均直徑2.2 釐米的珠粒。接著對亦含有Al2〇3的這些珠粒進行熱解， 然後燒結’則珠粒顯示具有i . i釐米的直徑。在進一步實 施例（實施例4 )中，未乾燥的珠粒平均具有3 · 1 3釐米的直 徑。乾燥之後（此部份並未進一步詳細解釋），直徑不高於 〇 · 8釐米。因此，可假設那些珠粒的孔隙度在乾燥期間顯 著地降低。 【發明內容】 本發明製備多孔纖維素體方法所包含之步驟爲 -製備於三級胺氧化物，特別爲N -甲基-嗎啉-N -氧化 -10 - (6) (6)200418558 物，中的纖維素溶液， -所使用之纖維素具有由150至2000之平均聚合 度， -溶液顯不之纖維素濃度爲0.1至5重量％， -由纖維素溶液製造本體 -本體於沈澱劑中沈澱出，藉此得到已沈澱纖維素 體， -該沈澱劑爲用於沈澱纖維素之水性介質或水可溶 混非水性介質，其中非水性介質可溶解三級胺氧化物且與 超臨界溶劑可溶混，及 其特徵在於 -當使用水性介質爲沈澱劑時 -以水性介質洗出包含在已沈澱纖維素體中的三級 胺氧化物， -水性介質以與超臨界溶劑可溶混的液態交換介質 取代， -利用超臨界溶劑處理經交換介質濕潤的纖維素 體’藉此得到多孔纖維素體， -或當使用非水性介質爲沈澱劑時 -以非水性介質洗出包含在已沈澱纖維素體中的三 級胺氧化物， -利用超臨界溶劑處理經非水性介質濕潤的纖維素 體，藉此得到多孔纖維素體。 在本發明目的中，『纖維素』一詞意爲可溶解於三級 -11 > (7) (7)200418558 胺氧化物的纖維素、纖維素衍生物，及得自纖維素及/或 可溶解纖維素衍生物及溶解於Ν Μ Μ Ο中的其中聚合物， 例如聚醯胺樹脂，的混合物。 纖維素在三級胺氧化物，例如Ν Μ Μ Ο，的溶解作用爲 熟於此藝者所習知者，通常纖維素溶液係纖維素在水性三 級胺氧化物，較佳爲Ν -甲基-嗎啉-Ν -氧化物（Ν Μ Μ Ο )，的 懸浮液被蒸發出過量水而得。 在發明方法中，較佳爲使用二氧化碳爲超臨界溶劑。 使用超臨界二氧化碳處理纖維素已揭示在： -ΕΡ-Α 1，205,5 98(由漿泥中萃取出樹脂以改良吸收力） -PCT WO 2000/015668(藉由蒸氣爆炸蒸煮纖維素材 料）。 兩篇專利中均由乾燥纖維素開始，因此高度孔隙度濕 式凝膠網絡並非其中的主題。 適於於本發明目的做爲沈澱劑的有機溶劑爲可與水溶 混、在胺-氧化物溶液中做爲纖維素的沈澱劑、足以溶解 NMMO、會造成纖維素初級凝膠的儘可能地高度溶脹，及 應該易於與超臨界二氧化碳溶混。特別適合者爲包含I-4 個C原子的醇類，例如乙醇。丙酮亦可分別使用爲非水性 介質或做爲液體交換介質。 可做用爲沈澱劑的水性介質可包含水或水與其他溶劑 的混合物（但需維持纖維素進行沈澱的活性。 除此之外，沈澱劑（水性介質或非水性介質）可含有進 一步的成分，例如高體積溶劑（氧化胺）。 -12- (8) (8)200418558 當使用超臨界溶劑處理時，即爲進行所謂的超臨界乾 燥。在超臨界乾燥期間，孔隙中的液體-蒸汽界面會消 失。 在一個利用二氧化碳進行超臨界乾燥的較佳案例中， 利如經醇或丙酮濕潤的凝膠在壓熱器中使用過量的醇/丙 酮覆蓋（以避過早乾燥），然後緩緩增高溫度和co2-壓力， 及將該數値保持在高於C02臨界點（31 .l°c /73.8巴）一段時 間直至位於纖維素體內的溶劑被定量移除。接著，調整壓 力和溫度使C02爲氣態地緩緩移除。 至於與C〇2超臨界乾燥技術有關的一般性常識可參見 p. H. Tewari，A. J. Hunt， K.D. Lofftus 揭示於 J· Fricke(編輯）：氣凝膠（Springer Proc· Phys· 6)，Spinger， 柏林 1986 ， p. 31 。 在本發明的一個較佳具體實例中，纖維素溶液依本身 習知的方式成形爲模製體，例如利用模塑工具擠出或利用 f譯造成爲個別的模體。 這類模製體可例如爲纖維，薄膜，塊狀物或板片。 由纖維素溶液中亦可利用滴注該溶液而製成球形或珠 粒形粒子，例如述於W0 99/3 1 14 1的技術。更甚者，粒 子亦可能由噴射-切割（Jet-Cutter)技術（Messrs. Genialab) 以及振動噴嘴方式由溶劑中製得。 經由本發明方法，亦可能由多數個多孔纖維素粒子製 造出粉末。 在本發明方法中，一個進一步較佳具體實例的特徵在 -13- 200418558 Ο) 於纖維素體在利用超臨界溶劑處理之前，以交聯劑進行處 理，例如於w Ο 9 1 /0 9 8 7 8中所述者。 此外，依據本發明方法所製得之多孔纖維素體可進行 熱解作用。 本發明方法方可能是首次得到在乾燥態時具有孔隙度 爲 85 %或更高的多孔纖維素體。因此，經過超臨界溶劑 處理而得的本體是一種高孔隙度氣凝膠。本發明之纖維素 體具有之孔隙度較佳爲90%或更高，特別佳爲95%或更 高。 依據本發明目的，孔隙度之測定如下：所得到的纖維 素體在顯微鏡下測量，並由之計算出體積。稱重纖維素 體，由此生成本體密度（質量/體量）。依據方程式ί(1 —本 體密度/1.6) * 1〇〇，由所測得之纖維素體密度衍生出本體 之孔隙度，亦即本體內中空空間的百分率。由於眾多的本 體數（例如珠粒），可由數次度量中取得平均値。 此外’本發明係有關於一種得自本發明方法之多孔纖 維素體。該本體相較於由胺·氧化物方法所製得之習知多 孔纖維素體，例如分別述於 WO 99/31141或 WO 0 2/0573 19 ’其差異性在於於乾燥態的孔隙度顯著地更 高。 由於本發明纖維素體的低密度，它們可特別地使用爲 絕緣材料’例如用於熱或聲音的絕緣。此外，本發明的纖 維素體亦可在電子和光電工業中做爲介電材料、用於聲學 應用中阻抗匹配、做爲吸收及純化氣體的元件、做爲催化 -14- (10) (10)200418558 劑載體及/或做爲儲存能量載體，例如氫，的元件。 更甚者，本發明係有關於一種由本發明纖維體經由熱 解而得到的多孔碳體。 對於碳體的應用領域已特別地引起注意。得自於纖維 素內容物熱解的碳氣凝膠可適用爲電極材料而應用於電 池’蓄電池，冷凝器和燃料電池，以及應用於高溫絕緣。 同時，這些碳-氣凝膠與碳奈米管類似地可做爲有效率的 氫儲存器。 【實施方式】 實施例： 依據本身所習知之方式製備出纖維素溶液，淇包含1 重量％之纖維素（具有依據SCAN CM 15:88 500黏度之 Solucell漿泥）/82重量％之NMMO/17重量％H20。將該溶 液滴注至做爲沈澱劑之水中，溶劑以水淸洗出，接著以乙 醇取代水。 經乙醇濕潤之本體（直徑約3釐米的球粒）被置入壓熱 器內’以額外的乙醇覆蓋，加熱至50°C並注入130巴的 C ◦ 2達2 · 5小時。循環C 0 2，使得在循環中的壓力在兩個 階段下分別降至60或4〇巴，其中每種情況下均利用到液 體分離器，然後C02再壓縮回到130巴。在上述的二個半 小時之後，C02在50°C下釋出。 得到與起始濕潤產物相同直徑（約3釐米）的纖維素球 粒。纖維素球粒的密度爲0.042 g/cm3，依據上文所示的 -15- (11) 200418558 計算方程式，這表示孔隙體積數量爲9 7.4%。 -16-In one example (Example 2), beads having an average diameter of 2.2 cm were obtained. These beads, which also contain Al203, are then pyrolyzed and then sintered ', and the beads show a diameter of 1.1 cm. In a further embodiment (Example 4), the undried beads have an average diameter of 3.13 cm. After drying (this section is not explained in further detail), the diameter is not higher than 0.8 cm. Therefore, it can be assumed that the porosity of those beads decreases significantly during drying. [Summary of the Invention] The method for preparing a porous cellulose body of the present invention includes the steps of-preparing from a tertiary amine oxide, especially N-methyl-morpholine-N-oxidizing-10-(6) (6) 200418558 Cellulose solution in,-the cellulose used has an average degree of polymerization from 150 to 2000,-the cellulose concentration of the solution is 0.1 to 5% by weight,-the body is made from the cellulose solution-the body is in a precipitant Precipitated cellulose, thereby obtaining a precipitated cellulose body, the precipitating agent is an aqueous medium or a water-miscible non-aqueous medium for precipitating cellulose, wherein the non-aqueous medium can dissolve tertiary amine oxides and is Solvent miscible, and is characterized by-when using an aqueous medium as a precipitant-washing out the tertiary amine oxide contained in the precipitated cellulose body in an aqueous medium,-the aqueous medium is miscible with the supercritical solvent Replacement of the liquid exchange medium,-treating the wetted cellulose body with the exchange medium with a supercritical solvent to thereby obtain a porous cellulose body,-or when using a non-aqueous medium as a precipitant-washing out with a non-aqueous medium Precipitation fiber The tertiary amine oxide in the body,-The cellulose body wetted with a non-aqueous medium is treated with a supercritical solvent, thereby obtaining a porous cellulose body. For the purposes of the present invention, the term "cellulose" means cellulose, cellulose derivatives which are soluble in tertiary -11 > (7) (7) 200418558 amine oxides, and derived from cellulose and / or A mixture of soluble cellulose derivatives and polymers therein, such as polyamide resins, dissolved in NM MO. The solubility of cellulose in tertiary amine oxides, such as NM Μ Ο, is known to those skilled in the art. Generally, the cellulose solution is cellulose in aqueous tertiary amine oxides, preferably N-formaldehyde. A suspension of propyl-morpholine-N-oxide (NM M 0) was obtained by evaporation of excess water. In the inventive method, it is preferable to use carbon dioxide as a supercritical solvent. Treatment of cellulose with supercritical carbon dioxide has been revealed in: -EP-A 1,205,5 98 (resin extracted from pulp to improve absorption)-PCT WO 2000/015668 (cooking cellulose material by steam explosion) . Both patents start with dried cellulose, so a highly porous wet gel network is not the subject of it. Organic solvents suitable as precipitants for the purposes of the present invention are precipitants that are miscible with water and act as cellulose in an amine-oxide solution, sufficient to dissolve NMMO and cause the cellulose primary gel to be as high as possible Swell and should be easily miscible with supercritical carbon dioxide. Particularly suitable are alcohols containing 1 to 4 C atoms, such as ethanol. Acetone can also be used separately as a non-aqueous medium or as a liquid exchange medium. The aqueous medium that can be used as a precipitant can include water or a mixture of water and other solvents (but it is necessary to maintain the activity of cellulose to precipitate. In addition, the precipitant (aqueous or non-aqueous medium) can contain further ingredients , Such as high-volume solvents (amine oxides). -12- (8) (8) 200418558 When supercritical solvent treatment is used, so-called supercritical drying is performed. During supercritical drying, the liquid-vapor interface in the pores In a preferred case of supercritical drying using carbon dioxide, gels moistened with alcohol or acetone are covered with an excess of alcohol / acetone in an autoclave (to avoid premature drying), then slowly Increase the temperature and co2-pressure, and keep the number above the C02 critical point (31.l ° c / 73.8 bar) for a period of time until the solvent in the cellulose is quantitatively removed. Then, adjust the pressure and temperature so that C02 is slowly removed in the gaseous state. For general knowledge about the C02 supercritical drying technology, see p. H. Tewari, AJ Hunt, and KD Lofftus. Revealed in J. Fricke (edition): Gas condensation Glue (Springer Proc. Phys. 6), Spinger, Berlin 1986, p. 31. In a preferred embodiment of the present invention, the cellulose solution is formed into a molded body in a manner known per se, such as by using a molding tool Extrude or use f to produce individual mold bodies. Such molded bodies can be, for example, fibers, films, lumps or plates. From cellulose solutions, spherical solutions or beads can be made by dripping the solution. Granular particles, such as the technology described in WO 99/3 1 14 1. Furthermore, the particles may also be made from a solvent by Jet-Cutter technology (Messrs. Genialab) and a vibrating nozzle method. In the method of the present invention, it is also possible to make a powder from a plurality of porous cellulose particles. In the method of the present invention, a further preferred embodiment is characterized by -13-200418558 0) before the cellulose body is treated with a supercritical solvent, Treatment with a cross-linking agent, such as described in w 0 9 1/0 9 8 7 8. In addition, the porous cellulose body produced according to the method of the present invention can be pyrolyzed. The method of the present invention may be the first time that a porous cellulose body having a porosity of 85% or more in a dry state is obtained. Therefore, the body obtained by supercritical solvent treatment is a high-porosity aerogel. The cellulose body of the present invention preferably has a porosity of 90% or more, particularly preferably 95% or more. According to the purpose of the present invention, the porosity is measured as follows: The obtained fibrous body is measured under a microscope, and the volume is calculated therefrom. The cellulosic body is weighed, thereby generating bulk density (mass / mass). According to the equation ί (1—body density / 1.6) * 100, the porosity of the body is derived from the measured cellulose body density, that is, the percentage of hollow space in the body. Due to the large number of bodies (such as beads), the average radon can be obtained from several measurements. Furthermore, the present invention relates to a porous cellulose body obtained from the method of the present invention. Compared with the conventional porous cellulose body prepared by the amine-oxide method, this body is described in WO 99/31141 or WO 0 2/0573 19 ', the difference is that the porosity in the dry state is significantly higher. Due to the low density of the cellulose bodies of the present invention, they can be used in particular as insulation materials', e.g. for heat or sound insulation. In addition, the cellulose body of the present invention can also be used as a dielectric material in the electronics and optoelectronic industries, used for impedance matching in acoustic applications, as an element for absorbing and purifying gases, and as a catalyst-14- (10) (10 ) 200418558 Dosage carrier and / or element for storing energy carrier, such as hydrogen. Furthermore, the present invention relates to a porous carbon body obtained by pyrolyzing the fibrous body of the present invention. Special attention has been paid to the field of application of carbon bodies. Carbon aerogels derived from pyrolysis of cellulose content are applicable as electrode materials for batteries' accumulators, condensers and fuel cells, and for high temperature insulation. At the same time, these carbon-aerogels act like carbon nanotubes as efficient hydrogen reservoirs. [Embodiment] Example: A cellulose solution is prepared according to a manner known per se. Qi contains 1% by weight of cellulose (with Solucell sludge according to SCAN CM 15:88 500 viscosity) / 82% by weight of NMMO / 17 Wt% H20. This solution was dripped into water as a precipitant, the solvent was washed out with water, and then water was replaced with ethanol. The body moistened with ethanol (spheres with a diameter of about 3 cm) was placed in an autoclave 'and covered with additional ethanol, heated to 50 ° C and injected with 130 bar of C ◦ 2 for 2.5 hours. Cycling C 0 2 reduces the pressure in the cycle to 60 or 40 bar in two stages, in each case using a liquid separator, and then CO 2 is compressed back to 130 bar. After two and a half hours, CO2 was released at 50 ° C. Cellulose pellets of the same diameter (about 3 cm) as the starting wet product were obtained. The density of cellulose pellets is 0.042 g / cm3. According to the equation shown above, -15- (11) 200418558 shows that the number of pore volumes is 9 7.4%. -16-