山東埃爾派 | 點擊(ji)量(liang):0次 | 2019-11-17
活性碳
活性碳(tan)(tan),又稱活性炭。是黑色粉(fen)末狀(zhuang)或塊狀(zhuang)、顆粒狀(zhuang)、蜂窩狀(zhuang)的(de)(de)無定形碳(tan)(tan),也有排列規整的(de)(de)晶體(ti)碳(tan)(tan)。活性炭中(zhong)除碳(tan)(tan)元素(su)(su)外,還包含(han)兩類摻和(he)物:一類是化學(xue)結(jie)合(he)的(de)(de)元素(su)(su),主要是氧(yang)和(he)氫,這些元素(su)(su)是由于未完(wan)全炭化而殘留在炭中(zhong),或者(zhe)在活化過程中(zhong),外來(lai)的(de)(de)非碳(tan)(tan)元素(su)(su)與活性炭表面化學(xue)結(jie)合(he)。
物料介紹
活(huo)(huo)性(xing)(xing)碳(tan),又稱活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)。是(shi)黑色(se)粉末(mo)狀(zhuang)或塊狀(zhuang)、顆粒狀(zhuang)、蜂窩狀(zhuang)的(de)(de)無(wu)定形碳(tan),也有排列規整的(de)(de)晶體碳(tan)。活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)中除碳(tan)元素外(wai),還包含兩類摻(chan)和物(wu):一(yi)類是(shi)化(hua)(hua)(hua)學(xue)結合的(de)(de)元素,主要是(shi)氧(yang)和氫,這些元素是(shi)由(you)于未完(wan)全(quan)炭(tan)(tan)(tan)化(hua)(hua)(hua)而殘留在(zai)炭(tan)(tan)(tan)中,或者(zhe)在(zai)活(huo)(huo)化(hua)(hua)(hua)過(guo)程(cheng)中,外(wai)來的(de)(de)非碳(tan)元素與活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)表(biao)面化(hua)(hua)(hua)學(xue)結合,如(ru)用水蒸氣(qi)活(huo)(huo)化(hua)(hua)(hua)時(shi),活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)表(biao)面被氧(yang)化(hua)(hua)(hua)或水蒸氣(qi)氧(yang)化(hua)(hua)(hua);另一(yi)類摻(chan)和物(wu)是(shi)灰(hui)(hui)分(fen),它是(shi)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)的(de)(de)無(wu)機部分(fen);灰(hui)(hui)分(fen)在(zai)活(huo)(huo)性(xing)(xing)碳(tan)中易造成(cheng)二次(ci)污染。將有機原(yuan)料(liao)(果殼、煤、木(mu)材等)在(zai)隔(ge)絕(jue)空氣(qi)的(de)(de)條(tiao)件下加熱,以減少非碳(tan)成(cheng)分(fen)(此過(guo)程(cheng)稱為(wei)炭(tan)(tan)(tan)化(hua)(hua)(hua)),然(ran)后與氣(qi)體反應,表(biao)面被侵蝕(shi)(shi),產(chan)生微孔(kong)發達的(de)(de)結構(此過(guo)程(cheng)稱為(wei)活(huo)(huo)化(hua)(hua)(hua))。由(you)于活(huo)(huo)化(hua)(hua)(hua)的(de)(de)過(guo)程(cheng)是(shi)一(yi)個微觀過(guo)程(cheng),即大量(liang)(liang)的(de)(de)分(fen)子碳(tan)化(hua)(hua)(hua)物(wu)表(biao)面侵蝕(shi)(shi)是(shi)點狀(zhuang)侵蝕(shi)(shi) ,所以造成(cheng)了活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)表(biao)面具有無(wu)數細小(xiao)孔(kong)隙。活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)表(biao)面的(de)(de)微孔(kong)直徑大多在(zai)2~50nm之間,即使是(shi)少量(liang)(liang)的(de)(de)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan),也有巨(ju)大的(de)(de)表(biao)面積(ji),每(mei)克活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)的(de)(de)表(biao)面積(ji)為(wei)500~1500m2,活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)的(de)(de)一(yi)切(qie)應用,幾(ji)乎都基于活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)的(de)(de)這一(yi)特點。
通常為粉狀或粒狀具(ju)有很強(qiang)吸附能力的(de)多孔無定形炭(tan)。由(you)固態(tai)碳(tan)質物(wu)(如煤、木料、硬果殼、果核(he)、樹脂等)在(zai)隔絕空(kong)氣(qi)條(tiao)(tiao)件(jian)下(xia)經600~900℃高溫炭(tan)化(hua),然(ran)后(hou)在(zai)400~900℃條(tiao)(tiao)件(jian)下(xia)用(yong)空(kong)氣(qi)、二氧(yang)化(hua)碳(tan)、水(shui)蒸氣(qi)或三(san)者的(de)混(hun)合氣(qi)體進行氧(yang)化(hua)活化(hua)后(hou)獲得。
炭(tan)化使(shi)碳以外的(de)物(wu)質(zhi)(zhi)(zhi)(zhi)揮發,氧化活化可進一(yi)步去掉殘(can)留的(de)揮發物(wu)質(zhi)(zhi)(zhi)(zhi),產生新的(de)和擴大(da)原(yuan)有(you)的(de)孔隙,改善微孔結構(gou),增(zeng)加活性(xing)(xing)。低溫(400℃)活化的(de)炭(tan)稱L-炭(tan),高(gao)溫(900℃)活化的(de)炭(tan)稱H-炭(tan)。H-炭(tan)必須在惰性(xing)(xing)氣(qi)氛中冷卻,否則會轉(zhuan)變為L-炭(tan)。活性(xing)(xing)炭(tan)的(de)吸附性(xing)(xing)能與氧化活化時氣(qi)體的(de)化學(xue)性(xing)(xing)質(zhi)(zhi)(zhi)(zhi)及(ji)其(qi)濃度(du)、活化溫度(du)、活化程度(du)、活性(xing)(xing)炭(tan)中無機物(wu)組成及(ji)其(qi)含(han)量等因素有(you)關(guan),主要取決于活化氣(qi)體性(xing)(xing)質(zhi)(zhi)(zhi)(zhi)及(ji)活化溫度(du)。
活(huo)性炭(tan)的含(han)炭(tan)量(liang)、比表(biao)面(mian)積(ji)(ji)、灰分含(han)量(liang)及其水懸浮(fu)液的pH值皆隨活(huo)化(hua)溫度的提高(gao)而增(zeng)大。活(huo)化(hua)溫度愈(yu)(yu)高(gao),殘留(liu)的揮發物質揮發愈(yu)(yu)完全,微孔結構愈(yu)(yu)發達,比表(biao)面(mian)積(ji)(ji)和吸附(fu)活(huo)性愈(yu)(yu)大。
活性(xing)炭(tan)中(zhong)的(de)灰分組成及其含(han)量對炭(tan)的(de)吸附(fu)活性(xing)有(you)很(hen)大影(ying)響。灰分主要由K2O、Na2O、CaO、MgO、Fe2O3、Al2O3、P2O5、SO3、Cl-等組成,灰分含(han)量與制(zhi)取(qu)活性(xing)炭(tan)的(de)原(yuan)料有(you)關,而且,隨(sui)炭(tan)中(zhong)揮發物的(de)去(qu)除,炭(tan)中(zhong)的(de)灰分含(han)量增大。
活性碳的分類
由于原料來源、制造(zao)方法、外觀形狀和應用場(chang)合(he)不同,活(huo)性(xing)碳的(de)種(zhong)類很(hen)多(duo),到目前為止尚無(wu)精(jing)確的(de)統計材料,大約有上千個品種(zhong)。
按原料來源分
1. 木質活性碳
2. 獸骨、血碳
3. 礦物質原料活性碳(tan)
4. 其它原料的活性碳
5. 再生(sheng)活(huo)性碳
按制造方法分
1. 化學法活性碳(化學碳)
2. 物理法活性碳(tan)
3. 化學–物(wu)理(li)法(fa)或物(wu)理(li)–化學法(fa)活性碳
按外觀形狀分
1. 粉狀(zhuang)活性(xing)碳(tan)
2. 顆粒活(huo)性(xing)碳(tan)
3. 不(bu)定(ding)型顆(ke)料活性(xing)碳
4. 圓(yuan)柱形(xing)活性碳
5. 球形活性碳
6. 其它形狀的活性碳
按外觀形狀分
1.粉狀活性(xing)碳(Powdered activated carbon, PAC)
2.顆粒活(huo)性碳(Granular activated carbon, GAC)
3.成形活性(xing)碳(tan)(Extruded activated carbon, EAC )
——圓(yuan)柱形活性碳(tan)
——球(qiu)形活性碳(tan)(Bead activated carbon, BAC)
4.活性碳纖維
5.蜂窩活性碳
6.其它形狀的活性碳
按孔徑分
大孔 孔徑(jing)>500A°
過渡孔(kong) 孔(kong)徑(jing)20 ~500A°
微孔(kong)(kong) 孔(kong)(kong)徑 < 20A°(活性碳的表面積(ji)主要(yao)是由微孔(kong)(kong)提供的)
活性炭(tan)化學活化法
(1)磷(lin)酸活化法(fa)
磷(lin)酸(suan)法制備(bei)活(huo)性炭的過程中,磷(lin)酸(suan)與(yu)木(mu)質(zhi)纖維原料的作(zuo)(zuo)用(yong)機理可分為以下幾(ji)個方面(mian):潤脹作(zuo)(zuo)用(yong)、加速活(huo)化作(zuo)(zuo)用(yong)、脫(tuo)水作(zuo)(zuo)用(yong)、氧化作(zuo)(zuo)用(yong)和芳香縮(suo)合(he)作(zuo)(zuo)用(yong)。
磷酸(suan)(suan)活(huo)(huo)化(hua)(hua)法的(de)基本工(gong)藝包括(kuo)木(mu)(mu)屑篩選、干(gan)燥、磷酸(suan)(suan)溶液配制(zhi)、混合(或(huo)浸(jin)漬(zi)) 、炭(tan)(tan)化(hua)(hua)、活(huo)(huo)化(hua)(hua)、回(hui)收(shou)、漂洗(包括(kuo)酸(suan)(suan)處理和水洗)、離心(xin)脫(tuo)水、干(gan)燥與磨粉(fen)等工(gong)序,如生產顆粒(li)活(huo)(huo)性(xing)炭(tan)(tan)還需增(zeng)加(jia)捏合工(gong)藝。另外,附設專門的(de)廢氣(qi)(qi)凈化(hua)(hua)系統,回(hui)收(shou)煙(yan)氣(qi)(qi)中的(de)磷酸(suan)(suan)和炭(tan)(tan)粉(fen),減(jian)少對環境的(de)污染。磷酸(suan)(suan)活(huo)(huo)化(hua)(hua)法的(de)生產工(gong)藝中,要注(zhu)意在炭(tan)(tan)化(hua)(hua)段(duan)(duan)控制(zhi)度(du),讓磷酸(suan)(suan)充分滲透(tou)入木(mu)(mu)屑,再與活(huo)(huo)化(hua)(hua)段(duan)(duan)協同(tong)控制(zhi),可(ke)以明顯(xian)提高(gao)活(huo)(huo)性(xing)炭(tan)(tan)吸附能力,產品質量(liang)穩定(ding),同(tong)時適當降低活(huo)(huo)化(hua)(hua)溫度(du)對降低產品灰(hui)分有(you)利(li)。炭(tan)(tan)活(huo)(huo)化(hua)(hua)尾(wei)(wei)氣(qi)(qi)采用多段(duan)(duan)液相回(hui)收(shou)可(ke)以增(zeng)加(jia)磷酸(suan)(suan)和細炭(tan)(tan)粉(fen)的(de)回(hui)收(shou),采用高(gao)壓靜電方式也有(you)利(li)于尾(wei)(wei)氣(qi)(qi)中焦油(you)的(de)去除(chu)。
(2)氯化鋅(xin)活(huo)化法
ZnCl2在活化過程(cheng)中(zhong)使木質纖維原料發生(sheng)脫氫(qing)反應并進一步芳(fang)構(gou)化,從而(er)形成初步孔(kong)結構(gou),水洗脫除氯(lv)(lv)化鋅(xin)后(hou)即形成孔(kong)隙(xi)結構(gou)。此外還有(you)學者認為氯(lv)(lv)化鋅(xin)在炭化時形成新(xin)生(sheng)炭沉(chen)積的骨架(jia),當其(qi)被(bei)洗去(qu)之后(hou),炭的表面便暴露出來,構(gou)成了具有(you)吸附力的活性(xing)炭內表面。
氯化(hua)鋅活化(hua)工(gong)藝(yi)流程(cheng)與磷酸活化(hua)法工(gong)藝(yi)基本相似。氯化(hua)鋅法活性炭由于其孔徑(jing)分布(bu)相對集(ji)中(zhong)、吸附力強等特(te)點,一直受到(dao)國內(nei)外市場的青睞,需求(qiu)量逐年增加。
(3)氫氧化(hua)鉀活化(hua)法
KOH活化(hua)法是20世紀70年代(dai)興起的(de)(de)(de)(de)一(yi)種制(zhi)備高(gao)比表面(mian)積活性(xing)(xing)炭(tan)的(de)(de)(de)(de)活化(hua)工藝,其(qi)活化(hua)過程是將(jiang)原(yuan)料炭(tan)與數倍炭(tan)質量的(de)(de)(de)(de)KOH或(huo)NaOH混合,在不超過500℃下脫水后于(yu)800 ℃左右煅燒若干時(shi)間(jian),冷卻后將(jiang)產品洗滌至(zhi)中性(xing)(xing)即可(ke)得到活性(xing)(xing)炭(tan)。反應(ying)機理是活化(hua)過程中被消耗的(de)(de)(de)(de)炭(tan)主(zhu)要生成了碳酸鉀,同(tong)時(shi)在800℃左右,被炭(tan)還原(yuan)的(de)(de)(de)(de)金屬(shu)鉀(沸點762℃)析(xi)出,金屬(shu)鉀的(de)(de)(de)(de)蒸氣不斷進入碳原(yuan)子所構成的(de)(de)(de)(de)層與層之間(jian)進行活化(hua),這兩個反應(ying)使產物(wu)具有很大的(de)(de)(de)(de)比表面(mian)積。
KOH法活性(xing)炭(tan)主要應用在(zai)超級電(dian)容器領域。以椰殼(ke)為(wei)主要原料所制得的活性(xing)炭(tan)比表(biao)面積可接(jie)近(jin)3000m2/g,比電(dian)容可超過(guo)200F/g,同時還可表(biao)現出非(fei)常優良(liang)的儲氫(qing)和儲甲烷能力(li),在(zai)77K和100kPa的情況(kuang)下,儲氫(qing)量可達(da)到2.94%,壓力(li)提高(gao)至1MPa,儲氫(qing)量可達(da)4.82%。
活性炭(tan)物理活化法
物(wu)理(li)法(fa)(fa)通常又(you)稱(cheng)氣(qi)體(ti)活(huo)(huo)化(hua)(hua)(hua)法(fa)(fa),是(shi)將已炭化(hua)(hua)(hua)處理(li)的原料在(zai)800 ~1000℃的高溫(wen)下與(yu)水蒸(zheng)氣(qi),煙(yan)道氣(qi)(水蒸(zheng)氣(qi)、CO2、N2等的混合(he)氣(qi))、CO或空氣(qi)等活(huo)(huo)化(hua)(hua)(hua)氣(qi)體(ti)接觸,從而進行活(huo)(huo)化(hua)(hua)(hua)反應的過程。物(wu)理(li)活(huo)(huo)化(hua)(hua)(hua)法(fa)(fa)的基本工(gong)藝(yi)過程主要包括炭化(hua)(hua)(hua)、活(huo)(huo)化(hua)(hua)(hua)、除雜、破碎(球磨)、精(jing)制等工(gong)藝(yi),制備過程清潔(jie),液(ye)相污染少。
在(zai)制備(bei)過程(cheng)中(zhong)(zhong),具有氧化(hua)性(xing)的(de)(de)(de)高溫(wen)(wen)活(huo)化(hua)氣(qi)體無序碳原(yuan)子(zi)及(ji)雜原(yuan)子(zi)首先發生(sheng)(sheng)反應,使(shi)原(yuan)來(lai)封(feng)閉的(de)(de)(de)孔(kong)打開(kai),進而基本微(wei)(wei)晶表面(mian)(mian)暴(bao)露,然后活(huo)化(hua)氣(qi)體與基本微(wei)(wei)晶表面(mian)(mian)上(shang)的(de)(de)(de)碳原(yuan)子(zi)繼續發生(sheng)(sheng)氧化(hua)反應,使(shi)孔(kong)隙不斷擴大(da)。一些不穩定的(de)(de)(de)炭(tan)(tan)因(yin)氣(qi)化(hua)生(sheng)(sheng)成CO、CO2、H2和(he)其他(ta)碳化(hua)合物(wu)氣(qi)體,從而產(chan)(chan)生(sheng)(sheng)新的(de)(de)(de)孔(kong)隙,同時焦油(you)和(he)未炭(tan)(tan)化(hua)物(wu)等(deng)也被(bei)除去,最終得到活(huo)性(xing)炭(tan)(tan)產(chan)(chan)品。活(huo)性(xing)炭(tan)(tan)發達(da)的(de)(de)(de)比(bi)表面(mian)(mian)積(ji)(ji)則源自中(zhong)(zhong)孔(kong)、大(da)孔(kong)孔(kong)容的(de)(de)(de)增加,形(xing)成的(de)(de)(de)大(da)孔(kong)、中(zhong)(zhong)孔(kong)和(he)微(wei)(wei)孔(kong)的(de)(de)(de)相(xiang)互連接(jie)貫(guan)通。由于物(wu)理法工藝(yi)流程(cheng)相(xiang)對(dui)簡(jian)單,產(chan)(chan)生(sheng)(sheng)的(de)(de)(de)廢(fei)氣(qi)以(yi)(yi)CO2和(he)水蒸氣(qi)為(wei)主,對(dui)環境污染較小,而且最終得到的(de)(de)(de)活(huo)性(xing)炭(tan)(tan)產(chan)(chan)品比(bi)表面(mian)(mian)積(ji)(ji)高、孔(kong)隙結構(gou)發達(da)、應用(yong)范(fan)圍廣,因(yin)此(ci)世界范(fan)圍內的(de)(de)(de)活(huo)性(xing)炭(tan)(tan)生(sheng)(sheng)產(chan)(chan)廠家中(zhong)(zhong)70%以(yi)(yi)上(shang)都采用(yong)物(wu)理法生(sheng)(sheng)產(chan)(chan)活(huo)性(xing)炭(tan)(tan)。炭(tan)(tan)活(huo)化(hua)過程(cheng)中(zhong)(zhong)產(chan)(chan)生(sheng)(sheng)大(da)量的(de)(de)(de)余(yu)熱(re)(re),可(ke)滿足原(yuan)料烘干、余(yu)熱(re)(re)鍋爐制高溫(wen)(wen)蒸汽、產(chan)(chan)品的(de)(de)(de)洗滌(di)烘干等(deng)所需熱(re)(re)能。
活(huo)(huo)性炭物理-化(hua)學活(huo)(huo)化(hua)法
(1)物理(li)-化學一體化制(zhi)備技(ji)術
物(wu)(wu)(wu)理-化(hua)(hua)學(xue)(xue)活(huo)化(hua)(hua)法顧(gu)名思義就是結合(he)應(ying)用(yong)(yong)物(wu)(wu)(wu)理活(huo)化(hua)(hua)和(he)化(hua)(hua)學(xue)(xue)活(huo)化(hua)(hua)的方法,即炭先經化(hua)(hua)學(xue)(xue)法處(chu)理,隨后(hou)再進一步(bu)用(yong)(yong)物(wu)(wu)(wu)理法(水蒸氣或CO2)活(huo)化(hua)(hua)。國外研究人員通過(guo)H3PO4和(he)CO2聯合(he)活(huo)化(hua)(hua)法制得(de)了(le)比表面積高達3700m2/g 的超級活(huo)性(xing)(xing)炭,具體步(bu)驟(zou)是在85℃下先用(yong)(yong)H3PO4浸泡木質原(yuan)料,經450℃炭化(hua)(hua)4h后(hou)再用(yong)(yong)CO2活(huo)化(hua)(hua)。將物(wu)(wu)(wu)理法和(he)化(hua)(hua)學(xue)(xue)法聯合(he),利用(yong)(yong)物(wu)(wu)(wu)理法的炭化(hua)(hua)尾氣為化(hua)(hua)學(xue)(xue)法生(sheng)產供(gong)熱,實現生(sheng)產過(guo)程(cheng)無燃(ran)煤消耗,同時得(de)到物(wu)(wu)(wu)理法活(huo)性(xing)(xing)炭和(he)化(hua)(hua)學(xue)(xue)法活(huo)性(xing)(xing)炭。
(2)微(wei)波輔助(zhu)化學活化
由于在活(huo)(huo)性炭(tan)制備(bei)(bei)(bei)過程中(zhong),傳統的(de)爐(lu)膛加(jia)熱(re)(re)存在耗工(gong)、耗時且物(wu)料受(shou)熱(re)(re)不均(jun)(jun)的(de)缺點,因(yin)此(ci)微(wei)波(bo)的(de)引入可(ke)(ke)以實(shi)現物(wu)料內部均(jun)(jun)勻加(jia)熱(re)(re),同時可(ke)(ke)方便地快(kuai)速啟動和(he)停(ting)止,耗時比傳統工(gong)藝(yi)短得(de)多。因(yin)此(ci),微(wei)波(bo)輔(fu)助化(hua)學(xue)活(huo)(huo)化(hua)可(ke)(ke)以顯著縮短生(sheng)產(chan)時間,從而(er)極大地提高(gao)生(sheng)產(chan)效率(lv),亦可(ke)(ke)降低環境污(wu)染。通常(chang)的(de)磷(lin)酸法(fa)(fa)、氯(lv)化(hua)鋅法(fa)(fa)和(he)氫氧化(hua)鉀活(huo)(huo)化(hua)法(fa)(fa)均(jun)(jun)可(ke)(ke)采用微(wei)波(bo)加(jia)熱(re)(re),而(er)且研究表(biao)明微(wei)波(bo)加(jia)熱(re)(re)法(fa)(fa)亦可(ke)(ke)得(de)到高(gao)性能的(de)活(huo)(huo)性炭(tan),尤其適用于KOH活(huo)(huo)化(hua)法(fa)(fa)制備(bei)(bei)(bei)超級電容活(huo)(huo)性炭(tan)。然而(er)微(wei)波(bo)加(jia)熱(re)(re)制備(bei)(bei)(bei)活(huo)(huo)性炭(tan)仍處(chu)于實(shi)驗階(jie)段,主(zhu)要原因(yin)是設(she)備(bei)(bei)(bei)投資(zi)大,能耗高(gao)。
(3)催化活化
金(jin)屬(shu)類催化(hua)劑(ji)在(zai)含碳原(yuan)料(liao)表面(mian)可形成活(huo)(huo)(huo)性點,降(jiang)低(di)炭與水(shui)或(huo)CO2的(de)反(fan)應(ying)活(huo)(huo)(huo)化(hua)能(neng)(neng),從而降(jiang)低(di)活(huo)(huo)(huo)化(hua)溫度,提(ti)高反(fan)應(ying)速(su)率,形成發達的(de)孔(kong)隙(xi),同時(shi),金(jin)屬(shu)顆粒移動時(shi)也會(hui)產生孔(kong)道。催化(hua)劑(ji)在(zai)制備(bei)(bei)超(chao)級活(huo)(huo)(huo)性炭時(shi)可以降(jiang)低(di)活(huo)(huo)(huo)化(hua)溫度,大幅提(ti)高反(fan)應(ying)的(de)速(su)率,還(huan)可使制得的(de)活(huo)(huo)(huo)性炭孔(kong)徑分布均勻。雖(sui)然催化(hua)活(huo)(huo)(huo)化(hua)法(fa)制備(bei)(bei)活(huo)(huo)(huo)性炭具(ju)有上述諸多優勢(shi),但反(fan)應(ying)速(su)度過快可能(neng)(neng)會(hui)燒穿微孔(kong)壁(bi)面(mian),從而破壞微孔(kong)結構(gou)。
活(huo)性炭的(de)行(xing)業應用
(1)處理含油(you)污水(shui)
吸(xi)附(fu)法進(jin)行油水(shui)(shui)分離是利(li)用親油性(xing)材料,吸(xi)附(fu)廢(fei)水(shui)(shui)中的(de)溶解(jie)油及(ji)其它溶解(jie)性(xing)有(you)機物。最常用的(de)吸(xi)油材料是活性(xing)炭(tan),可(ke)吸(xi)附(fu)廢(fei)水(shui)(shui)中的(de)分散油、乳化油和溶解(jie)油。由于(yu)活性(xing)炭(tan)對油的(de)吸(xi)附(fu)容(rong)量有(you)限(一般(ban)為30~80mg/g)),成本高,再生(sheng)困難,通(tong)常只用作(zuo)含油廢(fei)水(shui)(shui)多(duo)級處(chu)理的(de)最后(hou)一級處(chu)理,出水(shui)(shui)含油質量濃度可(ke)降(jiang)至0.1~0.2mg/L 。
由于活性炭(tan)對水(shui)的(de)預處理要求高(gao),而且活性炭(tan)的(de)價格昂(ang)貴,因(yin)此在廢(fei)水(shui)處理中,活性炭(tan)主要用來(lai)去除廢(fei)水(shui)中的(de)微量污染物,以達到深(shen)度(du)凈化的(de)目的(de)。 煉油廠含油廢(fei)水(shui),先經(jing)(jing)隔油、氣浮和(he)生物處理,再經(jing)(jing)砂濾和(he)活性炭(tan)過(guo)濾深(shen)度(du)處理。廢(fei)水(shui)的(de)含酚量從(cong)0.1 mg/L(經(jing)(jing)生物處理后)降至0.005mg/L,含氰量從(cong)0.19mg/L降至0.048mg/L,COD從(cong)85mg/L 降至18mg/L。
(2)處理染(ran)料廢(fei)水(shui)
染料廢(fei)水(shui)成分復雜、水(shui)質變化大、色(se)度(du)(du)(du)深(shen)(shen)、濃度(du)(du)(du)大,處(chu)理困難(nan)。處(chu)理方法(fa)主要(yao)有(you)氧(yang)化、吸(xi)附(fu)、膜分離、絮凝、生物降解(jie)等。這些方法(fa)各(ge)有(you)優缺點,其中活(huo)(huo)性(xing)(xing)炭(tan)能有(you)效地去(qu)除廢(fei)水(shui)的色(se)度(du)(du)(du)和(he)COD。活(huo)(huo)性(xing)(xing)炭(tan)處(chu)理染料廢(fei)水(shui)在國內外都(dou)有(you)研究,但大多數(shu)是和(he)其它工(gong)藝耦合,活(huo)(huo)性(xing)(xing)炭(tan)吸(xi)附(fu)多用(yong)于深(shen)(shen)度(du)(du)(du)處(chu)理或(huo)將活(huo)(huo)性(xing)(xing)炭(tan)作(zuo)為載(zai)體和(he)催化劑,單獨使用(yong)活(huo)(huo)性(xing)(xing)炭(tan)處(chu)理較(jiao)高濃度(du)(du)(du)染料廢(fei)水(shui)的研究很少。
活性(xing)(xing)(xing)炭對染料(liao)廢(fei)(fei)水(shui)(shui)有良好的(de)(de)(de)脫(tuo)色(se)效(xiao)果(guo)。染料(liao)廢(fei)(fei)水(shui)(shui)的(de)(de)(de)脫(tuo)色(se)率隨溫度的(de)(de)(de)升高(gao)而(er)增加,而(er)pH值對染料(liao)廢(fei)(fei)水(shui)(shui)的(de)(de)(de)脫(tuo)色(se)效(xiao)果(guo)沒有太大的(de)(de)(de)影響。在最佳吸(xi)附(fu)工藝條(tiao)件(jian)下(xia),酸性(xing)(xing)(xing)品(pin)紅、堿性(xing)(xing)(xing)品(pin)紅廢(fei)(fei)水(shui)(shui)的(de)(de)(de)脫(tuo)色(se)率均>97%,出水(shui)(shui)的(de)(de)(de)色(se)度稀釋倍數≤50倍,COD<50mg/L,達到國(guo)家一級(ji)排放(fang)標(biao)準。
(3)處(chu)理(li)含汞廢(fei)水(shui)
重金屬污染物(wu)中(zhong)以汞(gong)的(de)(de)(de)毒性(xing)最大(da),當(dang)汞(gong)進入(ru)人體內,就會破壞酶和(he)其它蛋(dan)白質的(de)(de)(de)功能(neng)(neng)并影響(xiang)其重新合成。活性(xing)炭(tan)有(you)吸附(fu)汞(gong)和(he)含汞(gong)化(hua)合物(wu)的(de)(de)(de)性(xing)能(neng)(neng),但吸附(fu)能(neng)(neng)力有(you)限,只(zhi)適(shi)宜于(yu)處(chu)理含汞(gong)量(liang)低的(de)(de)(de)廢水(shui)。如(ru)果含汞(gong)的(de)(de)(de)濃度(du)較高,可以先用(yong)化(hua)學沉淀法處(chu)理,處(chu)理后含汞(gong)約1mg/L,高時可達2~3mg/L,然后再用(yong)活性(xing)炭(tan)做(zuo)進一步的(de)(de)(de)處(chu)理。
(4)處理含鉻廢(fei)水
活性炭表面存在(zai)大量的含氧基團(tuan)如羥(qian)基(-OH)、羧基(-COOH)等,它們都(dou)有(you)靜電吸附(fu)功能(neng)(neng),對六價鉻(ge)產生化學吸附(fu)作(zuo)用,能(neng)(neng)有(you)效地(di)吸附(fu)廢水中(zhong)的六價鉻(ge),吸附(fu)后的廢水可達到國家(jia)排放(fang)標準。
利用(yong)(yong)活(huo)性(xing)炭處理(li)含(han)鉻(ge)廢(fei)水(shui)是活(huo)性(xing)炭對溶(rong)液中六價鉻(ge)的物(wu)理(li)吸(xi)(xi)(xi)附、化(hua)(hua)學(xue)吸(xi)(xi)(xi)附、化(hua)(hua)學(xue)還原等綜合作用(yong)(yong)的結果(guo)。活(huo)性(xing)炭處理(li)含(han)鉻(ge)廢(fei)水(shui),吸(xi)(xi)(xi)附性(xing)能穩定,處理(li)效率高,操作費用(yong)(yong)低,有一定的社會(hui)效益(yi)和(he)經濟(ji)效益(yi)。因此(ci),用(yong)(yong)活(huo)性(xing)炭處理(li)含(han)鉻(ge)廢(fei)水(shui)已得(de)到廣(guang)泛應用(yong)(yong)。
(5)催(cui)化和負載催(cui)化劑(ji)
石(shi)墨(mo)化炭(tan)和無定型炭(tan)是活(huo)(huo)性(xing)炭(tan)晶型的(de)(de)組成部分(fen),因(yin)為(wei)具有不飽和鍵,所以表現出類似結晶缺陷(xian)的(de)(de)功能。活(huo)(huo)性(xing)炭(tan)因(yin)為(wei)結晶缺陷(xian)的(de)(de)存在而(er)被作為(wei)催化劑(ji)廣泛應(ying)用(yong),同時,因(yin)為(wei)其具有大(da)的(de)(de)比表面積及多(duo)孔結構,活(huo)(huo)性(xing)炭(tan)還被廣泛用(yong)作催化劑(ji)載體。
采用(yong)(yong)(yong)γ射(she)(she)線(xian)處理商品活(huo)(huo)性炭(tan),此(ci)過程可(ke)以在不影響活(huo)(huo)性炭(tan)物理性質(zhi)(zhi)的條件下(xia)改(gai)變活(huo)(huo)性炭(tan)表(biao)面化(hua)(hua)(hua)學特(te)性。通過紫外(wai)線(xian)輻(fu)(fu)射(she)(she)和模(mo)(mo)擬太(tai)陽(yang)(yang)光(guang)(guang)(guang)(guang)輻(fu)(fu)射(she)(she)研究了光(guang)(guang)(guang)(guang)催(cui)化(hua)(hua)(hua)中活(huo)(huo)性炭(tan)表(biao)面化(hua)(hua)(hua)學所發揮的作(zuo)用(yong)(yong)(yong)。結(jie)果表(biao)明,無論是(shi)(shi)紫外(wai)線(xian)還是(shi)(shi)模(mo)(mo)擬太(tai)陽(yang)(yang)光(guang)(guang)(guang)(guang)輻(fu)(fu)射(she)(she),活(huo)(huo)性炭(tan)都可(ke)以發揮光(guang)(guang)(guang)(guang)催(cui)化(hua)(hua)(hua)作(zuo)用(yong)(yong)(yong)。通過測定紫外(wai)線(xian)/活(huo)(huo)性炭(tan)和模(mo)(mo)擬太(tai)陽(yang)(yang)光(guang)(guang)(guang)(guang)/活(huo)(huo)性炭(tan)體系中羥基(ji)(ji)自(zi)(zi)(zi)由(you)基(ji)(ji)和超氧陰離子自(zi)(zi)(zi)由(you)基(ji)(ji)表(biao)明,由(you)活(huo)(huo)性炭(tan)充(chong)當光(guang)(guang)(guang)(guang)催(cui)化(hua)(hua)(hua)劑和光(guang)(guang)(guang)(guang)誘導反(fan)應(ying)物可(ke)以有效(xiao)消除雜質(zhi)(zhi)對反(fan)應(ying)的影響,體系中羥基(ji)(ji)自(zi)(zi)(zi)由(you)基(ji)(ji)和超氧陰離子自(zi)(zi)(zi)由(you)基(ji)(ji)的獲得遠(yuan)高(gao)于單純采用(yong)(yong)(yong)光(guang)(guang)(guang)(guang)輻(fu)(fu)射(she)(she)。這(zhe)為發展(zhan)自(zi)(zi)(zi)由(you)基(ji)(ji)化(hua)(hua)(hua)學和尋找新(xin)的自(zi)(zi)(zi)由(you)基(ji)(ji)反(fan)應(ying)提供了新(xin)的可(ke)能。
活(huo)(huo)性(xing)(xing)污(wu)泥(ni)因為成分復(fu)雜(za),導致(zhi)其厭(yan)氧(yang)腐(fu)化(hua)(hua)(hua)(hua)(hua)過程(cheng)緩(huan)慢。有學(xue)者將粒(li)(li)狀(zhuang)活(huo)(huo)性(xing)(xing)炭(tan)(tan)用(yong)于(yu)(yu)活(huo)(huo)性(xing)(xing)污(wu)泥(ni)的(de)(de)(de)厭(yan)氧(yang)腐(fu)化(hua)(hua)(hua)(hua)(hua),使活(huo)(huo)性(xing)(xing)污(wu)泥(ni)腐(fu)化(hua)(hua)(hua)(hua)(hua)過程(cheng)中甲烷(wan)產率(lv)提(ti)(ti)高(gao)(gao)了17.4%,同(tong)時使活(huo)(huo)性(xing)(xing)污(wu)泥(ni)腐(fu)化(hua)(hua)(hua)(hua)(hua)率(lv)提(ti)(ti)高(gao)(gao)了6.1%。另外在活(huo)(huo)性(xing)(xing)炭(tan)(tan)表(biao)(biao)面引入(ru)-SO3H,對合成甲基叔戊基醚過程(cheng)有催(cui)化(hua)(hua)(hua)(hua)(hua)作(zuo)用(yong),該(gai)催(cui)化(hua)(hua)(hua)(hua)(hua)劑(ji)制備方便,催(cui)化(hua)(hua)(hua)(hua)(hua)活(huo)(huo)性(xing)(xing)高(gao)(gao)且不易分解,體現(xian)出改性(xing)(xing)活(huo)(huo)性(xing)(xing)炭(tan)(tan)催(cui)化(hua)(hua)(hua)(hua)(hua)劑(ji)的(de)(de)(de)巨大應用(yong)潛(qian)能。有研究(jiu)表(biao)(biao)明采(cai)用(yong)粒(li)(li)狀(zhuang)活(huo)(huo)性(xing)(xing)炭(tan)(tan)負(fu)載臭氧(yang)體系(xi)使腐(fu)殖(zhi)酸的(de)(de)(de)催(cui)化(hua)(hua)(hua)(hua)(hua)氧(yang)化(hua)(hua)(hua)(hua)(hua)率(lv)達(da)到48.1%,為腐(fu)殖(zhi)酸的(de)(de)(de)降解提(ti)(ti)供(gong)了新的(de)(de)(de)途徑。通過活(huo)(huo)性(xing)(xing)炭(tan)(tan)負(fu)載氧(yang)化(hua)(hua)(hua)(hua)(hua)鋁作(zuo)為改性(xing)(xing)活(huo)(huo)性(xing)(xing)炭(tan)(tan)糊電極用(yong)于(yu)(yu)苯(ben)酚的(de)(de)(de)電催(cui)化(hua)(hua)(hua)(hua)(hua)氧(yang)化(hua)(hua)(hua)(hua)(hua)研究(jiu),表(biao)(biao)現(xian)出了較(jiao)好的(de)(de)(de)穩定性(xing)(xing)和可重復(fu)使用(yong)性(xing)(xing),同(tong)時具有相對較(jiao)低的(de)(de)(de)檢出限和較(jiao)寬的(de)(de)(de)檢測范(fan)圍。
(6)臨床醫用
活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)由于其良好(hao)(hao)的(de)(de)(de)吸附(fu)性(xing)(xing)(xing)(xing)(xing)能,可用(yong)于急(ji)性(xing)(xing)(xing)(xing)(xing)臨床胃腸(chang)解毒急(ji)救,其具有(you)不被胃腸(chang)道吸收且無刺激性(xing)(xing)(xing)(xing)(xing)、可以(yi)直接口服、簡(jian)單(dan)便(bian)利(li)等優點;同(tong)時,活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)也被用(yong)于血液凈化和(he)癌癥治(zhi)療(liao)等。結(jie)腸(chang)直腸(chang)癌是(shi)(shi)常(chang)見(jian)的(de)(de)(de)惡性(xing)(xing)(xing)(xing)(xing)腫瘤。研(yan)究表明(ming)(ming)(ming),以(yi)納(na)米(mi)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)作(zuo)(zuo)(zuo)示蹤劑可以(yi)有(you)效增加結(jie)腸(chang)直腸(chang)癌患者淋巴結(jie)檢測次數。活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)纖(xian)維具有(you)兩種特性(xing)(xing)(xing)(xing)(xing):一是(shi)(shi)吸附(fu)性(xing)(xing)(xing)(xing)(xing)能;二是(shi)(shi)遠紅外放射性(xing)(xing)(xing)(xing)(xing)能。將銀吸附(fu)在活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)纖(xian)維上,用(yong)于治(zhi)療(liao)慢(man)性(xing)(xing)(xing)(xing)(xing)創面患者,在接受治(zhi)療(liao)的(de)(de)(de)數月內傷口沒有(you)任(ren)何(he)不良反應。有(you)學(xue)者以(yi)椰殼活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)為(wei)載(zai)(zai)體(ti)負(fu)載(zai)(zai)加替沙(sha)星(xing),結(jie)果(guo)表明(ming)(ming)(ming),其對(dui)加替沙(sha)星(xing)負(fu)載(zai)(zai)能力(li)較好(hao)(hao),可以(yi)用(yong)作(zuo)(zuo)(zuo)加替沙(sha)星(xing)的(de)(de)(de)緩釋載(zai)(zai)體(ti)。對(dui)選用(yong)撲熱息疼和(he)布洛(luo)芬(fen)作(zuo)(zuo)(zuo)為(wei)模型藥物,采用(yong)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)作(zuo)(zuo)(zuo)為(wei)藥物載(zai)(zai)體(ti)的(de)(de)(de)研(yan)究表明(ming)(ming)(ming),活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)顆(ke)粒(li)表現出(chu)非(fei)常(chang)低的(de)(de)(de)細胞毒性(xing)(xing)(xing)(xing)(xing),該研(yan)究為(wei)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)作(zuo)(zuo)(zuo)為(wei)無定型藥物載(zai)(zai)體(ti)提供(gong)了支持。有(you)學(xue)者單(dan)純利(li)用(yong)每日(ri)兩次直腸(chang)局(ju)部注入高(gao)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)粒(li)狀(zhuang)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭(tan)來治(zhi)療(liao)簡(jian)單(dan)的(de)(de)(de)慢(man)性(xing)(xing)(xing)(xing)(xing)肛瘺(lou),結(jie)果(guo)表明(ming)(ming)(ming),這種治(zhi)療(liao)方法效果(guo)良好(hao)(hao)、安全性(xing)(xing)(xing)(xing)(xing)高(gao),并且相較于其它治(zhi)療(liao)方法,病人更容易(yi)接受,為(wei)慢(man)性(xing)(xing)(xing)(xing)(xing)肛瘺(lou)的(de)(de)(de)治(zhi)愈提供(gong)了新(xin)的(de)(de)(de)策(ce)略。
(7)用于超級電(dian)容(rong)器電(dian)極
超(chao)(chao)級電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)主(zhu)要由電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)材(cai)(cai)料(liao)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)解(jie)液(ye)、集流體和(he)隔膜等部分組成(cheng)(cheng),其中(zhong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極材(cai)(cai)料(liao)直接(jie)決定著電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)性(xing)(xing)(xing)能(neng)的(de)高低(di)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)具有(you)比表(biao)面(mian)積(ji)大、孔(kong)隙發達(da)及(ji)容(rong)(rong)易(yi)制(zhi)(zhi)(zhi)備等優點,成(cheng)(cheng)為了(le)超(chao)(chao)級電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)最早應用的(de)碳質(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極材(cai)(cai)料(liao)。可(ke)通過對(dui)傳統(tong)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)的(de)改性(xing)(xing)(xing),制(zhi)(zhi)(zhi)備新型及(ji)高性(xing)(xing)(xing)能(neng)的(de)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極材(cai)(cai)料(liao)。以(yi)聚偏(pian)二氯(lv)乙烯(xi)為前驅體,只通過炭(tan)(tan)化(hua)處理(li)(li)而無(wu)需其它后(hou)處理(li)(li)制(zhi)(zhi)(zhi)備出比表(biao)面(mian)積(ji)1200m2·g-1、孔(kong)容(rong)(rong)0.48cm3·g-1的(de)多孔(kong)炭(tan)(tan),其最高比電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)為262F·g-1,電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極密度在0.8g·cm-3左右,體積(ji)比電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)可(ke)達(da)214F·cm-3,是(shi)一種(zhong)有(you)發展前途(tu)的(de)超(chao)(chao)級電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極材(cai)(cai)料(liao)。另有(you)研(yan)究將(jiang)(jiang)廢棄茶葉(xie)炭(tan)(tan)化(hua)后(hou)再用KOH活(huo)(huo)(huo)(huo)(huo)化(hua),制(zhi)(zhi)(zhi)備了(le)具有(you)無(wu)定型特(te)征的(de)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan),其具有(you)比表(biao)面(mian)積(ji)介于2245~2184m2·g-1的(de)多孔(kong)結(jie)(jie)構(gou)(gou),用其作(zuo)為超(chao)(chao)級電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極,以(yi)KOH水溶液(ye)作(zuo)為電(dian)(dian)(dian)(dian)(dian)(dian)(dian)解(jie)液(ye),比電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)高達(da)330F·g-1,充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)2000次后(hou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)略有(you)下(xia)降,為初始電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)的(de)92%,表(biao)現(xian)出良好的(de)循(xun)環(huan)性(xing)(xing)(xing)能(neng)。若使(shi)用蓮花花粉(fen)作(zuo)為碳源和(he)自模板,CO2為活(huo)(huo)(huo)(huo)(huo)化(hua)劑制(zhi)(zhi)(zhi)備活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)微粒,制(zhi)(zhi)(zhi)備的(de)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)具有(you)三維(wei)納米網格(ge)骨架構(gou)(gou)成(cheng)(cheng)的(de)多孔(kong)空(kong)心(xin)結(jie)(jie)構(gou)(gou),將(jiang)(jiang)這種(zhong)特(te)殊的(de)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)用作(zuo)超(chao)(chao)級電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)器(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極,其比電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)高達(da) 244F·g-1,充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)10000次后(hou)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)無(wu)衰減。
(8)用于儲氫
常用(yong)儲氫(qing)(qing)方法有高壓氣態儲氫(qing)(qing)、液化儲氫(qing)(qing)、金屬合金儲氫(qing)(qing)和(he)有機液體氫(qing)(qing)化物儲氫(qing)(qing)、炭(tan)(tan)材料(liao)(liao)儲氫(qing)(qing)等(deng)(deng),其中(zhong)炭(tan)(tan)材料(liao)(liao)主要有超(chao)(chao)級活(huo)(huo)性炭(tan)(tan)、納(na)米(mi)碳(tan)(tan)纖維以及(ji)碳(tan)(tan)納(na)米(mi)管等(deng)(deng),而超(chao)(chao)級活(huo)(huo)性炭(tan)(tan)因為原料(liao)(liao)豐富、比(bi)表(biao)面(mian)積大、表(biao)面(mian)化學(xue)性能修飾、儲氫(qing)(qing)量大、解吸速(su)度快(kuai)、循環使(shi)用(yong)壽命長以及(ji)容(rong)易產業(ye)化受(shou)到廣泛關注。有學(xue)者利用(yong) CO2活(huo)(huo)化模(mo)板(ban)制備多孔碳(tan)(tan),獲得了微孔介于(yu)0.7~1.3nm、中(zhong)孔介于(yu)2~4nm、比(bi)表(biao)面(mian)積2829m2·g-1、孔容(rong)2.34cm3·g-1的超(chao)(chao)級活(huo)(huo)性炭(tan)(tan)材料(liao)(liao),其在(zai)室溫298K、中(zhong)等(deng)(deng)壓強(qiang)8MPa條件下(xia),對氫(qing)(qing)的吸附量可(ke)達0.95%。
21世紀(ji)以來,類似于金屬-有(you)(you)機(ji)框架的(de)(de)多孔固體材(cai)料為氫(qing)(qing)的(de)(de)吸(xi)收儲(chu)(chu)存開辟了新的(de)(de)發展方向(xiang)。有(you)(you)學者在溫和(he)條件下(xia)將活(huo)性(xing)(xing)炭(tan)(tan)引入到金屬-有(you)(you)機(ji)框架材(cai)料中,合(he)成了具有(you)(you)高比(bi)表面積(ji)(ji)的(de)(de)活(huo)性(xing)(xing)炭(tan)(tan)-金屬-有(you)(you)機(ji)框架混(hun)合(he)材(cai)料,在77K、10 MPa條件下(xia),對(dui)氫(qing)(qing)的(de)(de)吸(xi)附量從(cong)8.2%提高到了13.5%。控制(zhi)超級活(huo)性(xing)(xing)炭(tan)(tan)制(zhi)備工藝,得到適宜儲(chu)(chu)氫(qing)(qing)的(de)(de)比(bi)表面積(ji)(ji)和(he)孔徑大小及分(fen)布,進而進行表面修飾,在室溫及中等(deng)壓強下(xia),提高儲(chu)(chu)氫(qing)(qing)量是超級活(huo)性(xing)(xing)炭(tan)(tan)儲(chu)(chu)氫(qing)(qing)研(yan)究及應(ying)用的(de)(de)關鍵。
(9)用于(yu)煙氣治理
活(huo)(huo)(huo)性(xing)炭(tan)材料在(zai)脫(tuo)硫(liu)脫(tuo)硝過程(cheng)(cheng)中,因其(qi)處理效(xiao)(xiao)果好、投資運行費用低、實現資源(yuan)化、且易于再生利(li)用等優(you)點而引人(ren)注(zhu)目(mu),但是,單一(yi)的活(huo)(huo)(huo)性(xing)炭(tan)脫(tuo)硫(liu),速度慢(man),效(xiao)(xiao)率(lv)低。在(zai)提高(gao)活(huo)(huo)(huo)性(xing)炭(tan)脫(tuo)硫(liu)的性(xing)能(neng)的過程(cheng)(cheng)中,改性(xing)活(huo)(huo)(huo)性(xing)炭(tan)引起(qi)重視,它能(neng)克(ke)服(fu)普(pu)通活(huo)(huo)(huo)性(xing)炭(tan)的某些缺(que)點和(he)(he)限制,被認為(wei)是最有前景的脫(tuo)硫(liu)劑之一(yi);另(ling)有研究表(biao)明,以亞鐵鹽和(he)(he)銅鹽配方(fang)處理的活(huo)(huo)(huo)性(xing)炭(tan)對氨(an)有很好的吸附性(xing)能(neng)。
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