活(huo)性(xing)炭(tan)(tan),是(shi)黑(hei)色粉末狀或塊狀、顆粒狀、蜂窩狀的無定形碳(tan)(tan)(tan),也有排列規(gui)整的晶體碳(tan)(tan)(tan)。活(huo)性(xing)炭(tan)(tan)中(zhong)除碳(tan)(tan)(tan)元(yuan)(yuan)素(su)外,還包含(han)兩類摻和物:一(yi)類是(shi)化學(xue)結合的元(yuan)(yuan)素(su),主要是(shi)氧和氫,這些元(yuan)(yuan)素(su)是(shi)由(you)于未(wei)完全炭(tan)(tan)化而(er)殘(can)留在(zai)炭(tan)(tan)中(zhong),或者在(zai)活(huo)化過(guo)程中(zhong),外來(lai)的非(fei)碳(tan)(tan)(tan)元(yuan)(yuan)素(su)與活(huo)性(xing)炭(tan)(tan)表面化學(xue)結合;另一(yi)類摻和物是(shi)灰(hui)分,它是(shi)活(huo)性(xing)炭(tan)(tan)的無機部分,灰(hui)分在(zai)活(huo)性(xing)碳(tan)(tan)(tan)中(zhong)易造成二次污染。活(huo)性(xing)炭(tan)(tan)由(you)于具有較(jiao)強的吸(xi)附性(xing),廣(guang)泛應用于生產、生活(huo)中(zhong)。
活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)材料(liao)(liao)是經(jing)過加(jia)工處理(li)(li)所得(de)的(de)(de)無定(ding)形碳,具有(you)很大(da)的(de)(de)比表(biao)面(mian)積,對(dui)氣體、溶(rong)液中的(de)(de)無機(ji)或有(you)機(ji)物(wu)質及膠體顆粒(li)等(deng)都有(you)良好的(de)(de)吸附能力。活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)材料(liao)(liao)主(zhu)要包括活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)(Activated Carbon , A C )和活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)纖維(Activated Carbon Fibers, ACF )等(deng)。活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)材料(liao)(liao)作為一種(zhong)性(xing)(xing)(xing)能優良的(de)(de)吸附劑(ji),主(zhu)要是由于(yu)其(qi)具有(you)獨特的(de)(de)吸附表(biao)面(mian)結構特性(xing)(xing)(xing)和表(biao)面(mian)化(hua)(hua)學性(xing)(xing)(xing)能所決(jue)定(ding)的(de)(de)。活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)材料(liao)(liao)的(de)(de)化(hua)(hua)學性(xing)(xing)(xing)質穩定(ding),機(ji)械強度高,耐(nai)酸、耐(nai)堿、耐(nai)熱,不溶(rong)于(yu)水與有(you)機(ji)溶(rong)劑(ji),可以再生(sheng)使用(yong),已(yi)經(jing)廣(guang)(guang)泛地應用(yong)于(yu)化(hua)(hua)工、環保(bao)、食品加(jia)工、冶金、藥物(wu)精制、軍事化(hua)(hua)學防(fang)護等(deng)各個領域(yu) 。目前,改性(xing)(xing)(xing)活(huo)(huo)(huo)(huo)性(xing)(xing)(xing)炭(tan)材料(liao)(liao)被廣(guang)(guang)泛用(yong)于(yu)污(wu)水處理(li)(li)、大(da)氣污(wu)染防(fang)治等(deng)領域(yu),在治理(li)(li)環境污(wu)染方(fang)面(mian)越(yue)來越(yue)顯示出其(qi)誘(you)人的(de)(de)美好前景。
活(huo)性(xing)炭(tan)(tan)(tan)80%-90%以上由(you)碳(tan)元素(su)組成,這也是(shi)(shi)(shi)活(huo)性(xing)炭(tan)(tan)(tan)為疏(shu)水(shui)性(xing)吸附劑的(de)原因。除(chu)了碳(tan)元素(su)外,還包(bao)含有兩類摻和(he)(he)物:一類是(shi)(shi)(shi)化(hua)(hua)學結合的(de)元素(su),主要(yao)是(shi)(shi)(shi)氧(yang)和(he)(he)氫,這些元素(su)是(shi)(shi)(shi)由(you)于未完全(quan)炭(tan)(tan)(tan)化(hua)(hua)而殘留在(zai)炭(tan)(tan)(tan)中(zhong),或者在(zai)活(huo)化(hua)(hua)過程(cheng)中(zhong),外來的(de)非碳(tan)元素(su)與活(huo)性(xing)炭(tan)(tan)(tan)表面(mian)化(hua)(hua)學結合,如用水(shui)蒸(zheng)氣活(huo)化(hua)(hua)時(shi),活(huo)性(xing)炭(tan)(tan)(tan)表面(mian)被(bei)氧(yang)化(hua)(hua)或水(shui)蒸(zheng)氣氧(yang)化(hua)(hua);另一類摻和(he)(he)物是(shi)(shi)(shi)灰(hui)分,它是(shi)(shi)(shi)活(huo)性(xing)炭(tan)(tan)(tan)的(de)無機部(bu)分。
活性(xing)(xing)(xing)炭的主(zhu)要原料幾乎可以是(shi)所(suo)有(you)(you)(you)富含碳的有(you)(you)(you)機(ji)(ji)材料,如煤、木(mu)材、果殼(ke)、椰(ye)殼(ke)、核(he)桃殼(ke)、杏殼(ke)、棗(zao)殼(ke)等。這些(xie)(xie)含碳材料在活化爐中(zhong),在高溫和(he)(he)一定壓(ya)力下通過(guo)熱解作(zuo)(zuo)用被轉換成活性(xing)(xing)(xing)炭。在此活化過(guo)程中(zhong),巨大(da)(da)的表面(mian)積和(he)(he)復雜的孔(kong)隙結構逐(zhu)漸形成, 而所(suo)謂(wei)的吸(xi)附過(guo)程正是(shi)在這些(xie)(xie)孔(kong)隙中(zhong)和(he)(he)表面(mian)上進行的,活性(xing)(xing)(xing)炭中(zhong)孔(kong)隙的大(da)(da)小對吸(xi)附質(zhi)(zhi)有(you)(you)(you)選(xuan)擇吸(xi)附的作(zuo)(zuo)用,這是(shi)由于(yu)大(da)(da)分子(zi)不能(neng)進入比它(ta)孔(kong)隙小的活性(xing)(xing)(xing)炭孔(kong)徑內的緣故。活性(xing)(xing)(xing)炭是(shi)由含炭為主(zhu)的物質(zhi)(zhi)作(zuo)(zuo)原料,經高溫炭化和(he)(he)活化制得(de)的疏水性(xing)(xing)(xing)吸(xi)附劑。活性(xing)(xing)(xing)炭含有(you)(you)(you)大(da)(da)量微孔(kong),具有(you)(you)(you)巨大(da)(da)無(wu)比的表面(mian)積,能(neng)有(you)(you)(you)效地去(qu)(qu)除(chu)色度(du)、臭味,可去(qu)(qu)除(chu)二級出水中(zhong)大(da)(da)多數有(you)(you)(you)機(ji)(ji)污染物和(he)(he)某些(xie)(xie)無(wu)機(ji)(ji)物,包含某些(xie)(xie)有(you)(you)(you)毒(du)的重金(jin)屬(shu)。