活(huo)性(xing)(xing)(xing)炭(tan)(tan),是(shi)黑色粉(fen)末狀(zhuang)(zhuang)(zhuang)或(huo)塊(kuai)狀(zhuang)(zhuang)(zhuang)、顆(ke)粒狀(zhuang)(zhuang)(zhuang)、蜂窩狀(zhuang)(zhuang)(zhuang)的無定(ding)形碳,也有排列規整的晶體碳。活(huo)性(xing)(xing)(xing)炭(tan)(tan)中除碳元(yuan)(yuan)(yuan)素外(wai),還包含兩類摻(chan)和(he)物:一類是(shi)化學結合(he)的元(yuan)(yuan)(yuan)素,主要是(shi)氧和(he)氫,這些元(yuan)(yuan)(yuan)素是(shi)由于未完全炭(tan)(tan)化而殘留在炭(tan)(tan)中,或(huo)者在活(huo)化過程(cheng)中,外(wai)來(lai)的非(fei)碳元(yuan)(yuan)(yuan)素與活(huo)性(xing)(xing)(xing)炭(tan)(tan)表面化學結合(he);另(ling)一類摻(chan)和(he)物是(shi)灰分,它是(shi)活(huo)性(xing)(xing)(xing)炭(tan)(tan)的無機部(bu)分,灰分在活(huo)性(xing)(xing)(xing)碳中易(yi)造成二次(ci)污染(ran)。活(huo)性(xing)(xing)(xing)炭(tan)(tan)由于具有較(jiao)強的吸附性(xing)(xing)(xing),廣(guang)泛應(ying)用(yong)于生產、生活(huo)中。
活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)材(cai)(cai)(cai)料是(shi)經過加(jia)工處理所得的(de)(de)無(wu)定形碳(tan),具(ju)有(you)(you)很大(da)(da)的(de)(de)比(bi)表面積,對氣(qi)體、溶液中的(de)(de)無(wu)機(ji)(ji)或(huo)有(you)(you)機(ji)(ji)物質及膠體顆(ke)粒(li)等都有(you)(you)良好的(de)(de)吸(xi)(xi)附能(neng)力。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)材(cai)(cai)(cai)料主(zhu)(zhu)要包括活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(Activated Carbon , A C )和(he)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)纖維(Activated Carbon Fibers, ACF )等。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)材(cai)(cai)(cai)料作為一種性(xing)(xing)(xing)(xing)能(neng)優良的(de)(de)吸(xi)(xi)附劑,主(zhu)(zhu)要是(shi)由于(yu)其(qi)具(ju)有(you)(you)獨特的(de)(de)吸(xi)(xi)附表面結構特性(xing)(xing)(xing)(xing)和(he)表面化(hua)學性(xing)(xing)(xing)(xing)能(neng)所決(jue)定的(de)(de)。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)材(cai)(cai)(cai)料的(de)(de)化(hua)學性(xing)(xing)(xing)(xing)質穩(wen)定,機(ji)(ji)械強度高(gao),耐酸、耐堿、耐熱,不溶于(yu)水與有(you)(you)機(ji)(ji)溶劑,可以再生使(shi)用(yong),已(yi)經廣泛(fan)地應用(yong)于(yu)化(hua)工、環保、食品加(jia)工、冶金、藥(yao)物精制、軍事(shi)化(hua)學防護等各個領域 。目前,改性(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)材(cai)(cai)(cai)料被廣泛(fan)用(yong)于(yu)污水處理、大(da)(da)氣(qi)污染防治等領域,在治理環境污染方(fang)面越來(lai)越顯示出其(qi)誘(you)人的(de)(de)美(mei)好前景。
活(huo)(huo)性(xing)炭80%-90%以上由碳元(yuan)素(su)組成,這(zhe)也(ye)是活(huo)(huo)性(xing)炭為疏(shu)水(shui)性(xing)吸附劑的(de)原因。除了(le)碳元(yuan)素(su)外,還包含有(you)兩類(lei)摻和(he)物(wu):一(yi)類(lei)是化(hua)(hua)學結合(he)的(de)元(yuan)素(su),主要是氧和(he)氫,這(zhe)些(xie)元(yuan)素(su)是由于未完(wan)全炭化(hua)(hua)而(er)殘留在炭中(zhong),或者在活(huo)(huo)化(hua)(hua)過(guo)程中(zhong),外來的(de)非碳元(yuan)素(su)與(yu)活(huo)(huo)性(xing)炭表面(mian)化(hua)(hua)學結合(he),如用水(shui)蒸氣活(huo)(huo)化(hua)(hua)時,活(huo)(huo)性(xing)炭表面(mian)被氧化(hua)(hua)或水(shui)蒸氣氧化(hua)(hua);另一(yi)類(lei)摻和(he)物(wu)是灰分(fen)(fen),它是活(huo)(huo)性(xing)炭的(de)無(wu)機部分(fen)(fen)。
活(huo)性炭(tan)的(de)(de)(de)主要原料(liao)幾乎可以(yi)是(shi)所有(you)富含(han)碳(tan)的(de)(de)(de)有(you)機(ji)材料(liao),如(ru)煤、木材、果殼(ke)、椰殼(ke)、核桃(tao)殼(ke)、杏殼(ke)、棗殼(ke)等。這(zhe)些含(han)碳(tan)材料(liao)在(zai)(zai)活(huo)化爐(lu)中(zhong)(zhong),在(zai)(zai)高溫和(he)一定壓(ya)力下通過熱解作用(yong)被轉換成活(huo)性炭(tan)。在(zai)(zai)此(ci)活(huo)化過程(cheng)中(zhong)(zhong),巨(ju)(ju)大(da)的(de)(de)(de)表(biao)面(mian)(mian)積和(he)復(fu)雜的(de)(de)(de)孔(kong)(kong)隙(xi)結(jie)構逐漸形成, 而所謂的(de)(de)(de)吸附過程(cheng)正是(shi)在(zai)(zai)這(zhe)些孔(kong)(kong)隙(xi)中(zhong)(zhong)和(he)表(biao)面(mian)(mian)上進行的(de)(de)(de),活(huo)性炭(tan)中(zhong)(zhong)孔(kong)(kong)隙(xi)的(de)(de)(de)大(da)小對吸附質(zhi)有(you)選擇吸附的(de)(de)(de)作用(yong),這(zhe)是(shi)由于大(da)分子不(bu)能(neng)進入比它(ta)孔(kong)(kong)隙(xi)小的(de)(de)(de)活(huo)性炭(tan)孔(kong)(kong)徑內的(de)(de)(de)緣(yuan)故。活(huo)性炭(tan)是(shi)由含(han)炭(tan)為(wei)主的(de)(de)(de)物(wu)(wu)質(zhi)作原料(liao),經高溫炭(tan)化和(he)活(huo)化制得的(de)(de)(de)疏水性吸附劑(ji)。活(huo)性炭(tan)含(han)有(you)大(da)量微孔(kong)(kong),具有(you)巨(ju)(ju)大(da)無比的(de)(de)(de)表(biao)面(mian)(mian)積,能(neng)有(you)效地(di)去除(chu)色度、臭味,可去除(chu)二級出水中(zhong)(zhong)大(da)多數有(you)機(ji)污染物(wu)(wu)和(he)某些無機(ji)物(wu)(wu),包含(han)某些有(you)毒的(de)(de)(de)重(zhong)金屬(shu)。