活(huo)性(xing)(xing)炭(tan)(tan),是黑色粉末狀或(huo)塊狀、顆粒狀、蜂窩狀的(de)(de)無定形碳(tan),也有(you)排列(lie)規整的(de)(de)晶體碳(tan)。活(huo)性(xing)(xing)炭(tan)(tan)中(zhong)(zhong)除碳(tan)元素(su)外,還包含兩類摻和(he)物(wu):一類是化學結合的(de)(de)元素(su),主要是氧和(he)氫,這些元素(su)是由于未完全(quan)炭(tan)(tan)化而殘留在炭(tan)(tan)中(zhong)(zhong),或(huo)者(zhe)在活(huo)化過(guo)程中(zhong)(zhong),外來的(de)(de)非碳(tan)元素(su)與活(huo)性(xing)(xing)炭(tan)(tan)表面化學結合;另一類摻和(he)物(wu)是灰(hui)分,它(ta)是活(huo)性(xing)(xing)炭(tan)(tan)的(de)(de)無機部(bu)分,灰(hui)分在活(huo)性(xing)(xing)碳(tan)中(zhong)(zhong)易造成二次污(wu)染。活(huo)性(xing)(xing)炭(tan)(tan)由于具有(you)較強的(de)(de)吸附性(xing)(xing),廣泛應用于生產、生活(huo)中(zhong)(zhong)。
活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)是(shi)經(jing)過加(jia)工(gong)處理所得(de)的(de)(de)(de)無定形碳,具有很大(da)的(de)(de)(de)比表面積,對氣體、溶(rong)液中(zhong)的(de)(de)(de)無機(ji)(ji)或有機(ji)(ji)物(wu)質及膠體顆粒(li)等(deng)(deng)(deng)都有良好(hao)的(de)(de)(de)吸附(fu)能(neng)力(li)。活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)主要(yao)包括活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)(Activated Carbon , A C )和活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)纖(xian)維(wei)(Activated Carbon Fibers, ACF )等(deng)(deng)(deng)。活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)作為一種性(xing)(xing)(xing)能(neng)優良的(de)(de)(de)吸附(fu)劑(ji),主要(yao)是(shi)由(you)于其(qi)具有獨特(te)的(de)(de)(de)吸附(fu)表面結(jie)構(gou)特(te)性(xing)(xing)(xing)和表面化學性(xing)(xing)(xing)能(neng)所決定的(de)(de)(de)。活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)的(de)(de)(de)化學性(xing)(xing)(xing)質穩定,機(ji)(ji)械強度高,耐(nai)酸、耐(nai)堿、耐(nai)熱,不溶(rong)于水(shui)與(yu)有機(ji)(ji)溶(rong)劑(ji),可以再(zai)生使(shi)用(yong),已經(jing)廣泛地應用(yong)于化工(gong)、環保、食品加(jia)工(gong)、冶金(jin)、藥物(wu)精制、軍(jun)事化學防(fang)護等(deng)(deng)(deng)各個領域(yu) 。目前(qian)(qian),改性(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)被廣泛用(yong)于污(wu)水(shui)處理、大(da)氣污(wu)染防(fang)治等(deng)(deng)(deng)領域(yu),在治理環境污(wu)染方(fang)面越來(lai)越顯示出其(qi)誘人的(de)(de)(de)美好(hao)前(qian)(qian)景。
活性(xing)炭80%-90%以上(shang)由碳(tan)元(yuan)素(su)組(zu)成(cheng),這也是(shi)(shi)活性(xing)炭為疏水性(xing)吸(xi)附劑的(de)原(yuan)因。除了碳(tan)元(yuan)素(su)外(wai),還(huan)包(bao)含有兩類(lei)摻(chan)和物:一(yi)類(lei)是(shi)(shi)化(hua)(hua)學結合的(de)元(yuan)素(su),主要(yao)是(shi)(shi)氧和氫,這些(xie)元(yuan)素(su)是(shi)(shi)由于未完全炭化(hua)(hua)而(er)殘留在炭中,或(huo)者在活化(hua)(hua)過程中,外(wai)來的(de)非碳(tan)元(yuan)素(su)與(yu)活性(xing)炭表面化(hua)(hua)學結合,如用(yong)水蒸(zheng)氣活化(hua)(hua)時,活性(xing)炭表面被氧化(hua)(hua)或(huo)水蒸(zheng)氣氧化(hua)(hua);另(ling)一(yi)類(lei)摻(chan)和物是(shi)(shi)灰(hui)分,它是(shi)(shi)活性(xing)炭的(de)無(wu)機部分。
活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)主(zhu)要(yao)原料幾乎可(ke)以是(shi)所(suo)有(you)富含碳的(de)有(you)機材(cai)料,如煤、木材(cai)、果殼、椰殼、核桃殼、杏殼、棗殼等。這些含碳材(cai)料在(zai)活(huo)(huo)(huo)化(hua)(hua)爐中(zhong)(zhong)(zhong),在(zai)高(gao)溫和(he)一定壓(ya)力(li)下(xia)通過熱(re)解作用被轉換成(cheng)活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)。在(zai)此活(huo)(huo)(huo)化(hua)(hua)過程中(zhong)(zhong)(zhong),巨(ju)大(da)(da)(da)的(de)表面積和(he)復雜的(de)孔隙(xi)(xi)(xi)(xi)結(jie)構(gou)逐(zhu)漸形成(cheng), 而(er)所(suo)謂的(de)吸(xi)附(fu)過程正是(shi)在(zai)這些孔隙(xi)(xi)(xi)(xi)中(zhong)(zhong)(zhong)和(he)表面上(shang)進(jin)(jin)行的(de),活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)中(zhong)(zhong)(zhong)孔隙(xi)(xi)(xi)(xi)的(de)大(da)(da)(da)小對吸(xi)附(fu)質有(you)選擇(ze)吸(xi)附(fu)的(de)作用,這是(shi)由(you)于大(da)(da)(da)分子不能進(jin)(jin)入比它孔隙(xi)(xi)(xi)(xi)小的(de)活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)孔徑內的(de)緣故。活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)是(shi)由(you)含炭(tan)(tan)(tan)(tan)(tan)為主(zhu)的(de)物(wu)質作原料,經高(gao)溫炭(tan)(tan)(tan)(tan)(tan)化(hua)(hua)和(he)活(huo)(huo)(huo)化(hua)(hua)制得的(de)疏(shu)水性(xing)(xing)吸(xi)附(fu)劑。活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)含有(you)大(da)(da)(da)量微孔,具有(you)巨(ju)大(da)(da)(da)無比的(de)表面積,能有(you)效地(di)去(qu)除(chu)色(se)度(du)、臭(chou)味,可(ke)去(qu)除(chu)二(er)級(ji)出水中(zhong)(zhong)(zhong)大(da)(da)(da)多數(shu)有(you)機污(wu)染物(wu)和(he)某些無機物(wu),包含某些有(you)毒的(de)重金屬(shu)。