活(huo)(huo)性(xing)(xing)炭(tan)(tan),是(shi)黑色粉末(mo)狀(zhuang)或塊狀(zhuang)、顆粒狀(zhuang)、蜂窩(wo)狀(zhuang)的無(wu)定(ding)形碳(tan),也(ye)有排列規(gui)整的晶體(ti)碳(tan)。活(huo)(huo)性(xing)(xing)炭(tan)(tan)中(zhong)除碳(tan)元素外(wai),還(huan)包含兩類摻(chan)和物:一類是(shi)化(hua)學結(jie)合的元素,主要是(shi)氧和氫,這些元素是(shi)由(you)于(yu)未完(wan)全炭(tan)(tan)化(hua)而殘留在(zai)炭(tan)(tan)中(zhong),或者在(zai)活(huo)(huo)化(hua)過程(cheng)中(zhong),外(wai)來的非碳(tan)元素與(yu)活(huo)(huo)性(xing)(xing)炭(tan)(tan)表面(mian)化(hua)學結(jie)合;另(ling)一類摻(chan)和物是(shi)灰分,它(ta)是(shi)活(huo)(huo)性(xing)(xing)炭(tan)(tan)的無(wu)機部分,灰分在(zai)活(huo)(huo)性(xing)(xing)碳(tan)中(zhong)易造(zao)成二次污(wu)染。活(huo)(huo)性(xing)(xing)炭(tan)(tan)由(you)于(yu)具有較強的吸(xi)附性(xing)(xing),廣(guang)泛應用于(yu)生產(chan)、生活(huo)(huo)中(zhong)。
活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)是經過加工處理所(suo)得的(de)無定形碳,具有(you)(you)(you)很(hen)大(da)的(de)比表面積,對氣(qi)體、溶液(ye)中的(de)無機(ji)(ji)或(huo)有(you)(you)(you)機(ji)(ji)物(wu)(wu)質(zhi)及膠體顆粒等(deng)(deng)都(dou)有(you)(you)(you)良好(hao)的(de)吸附(fu)能力。活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)主要(yao)包括活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(Activated Carbon , A C )和(he)活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)纖維(Activated Carbon Fibers, ACF )等(deng)(deng)。活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)作為(wei)一種性(xing)(xing)(xing)(xing)(xing)能優良的(de)吸附(fu)劑(ji),主要(yao)是由于(yu)其(qi)(qi)具有(you)(you)(you)獨特的(de)吸附(fu)表面結構特性(xing)(xing)(xing)(xing)(xing)和(he)表面化(hua)(hua)學(xue)(xue)性(xing)(xing)(xing)(xing)(xing)能所(suo)決定的(de)。活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)的(de)化(hua)(hua)學(xue)(xue)性(xing)(xing)(xing)(xing)(xing)質(zhi)穩定,機(ji)(ji)械強度高,耐(nai)酸、耐(nai)堿(jian)、耐(nai)熱,不溶于(yu)水(shui)與有(you)(you)(you)機(ji)(ji)溶劑(ji),可以再(zai)生使用(yong),已經廣泛(fan)地應用(yong)于(yu)化(hua)(hua)工、環保(bao)、食品加工、冶(ye)金、藥物(wu)(wu)精制、軍(jun)事化(hua)(hua)學(xue)(xue)防護等(deng)(deng)各個領域 。目前,改(gai)性(xing)(xing)(xing)(xing)(xing)活性(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)材(cai)料(liao)(liao)被廣泛(fan)用(yong)于(yu)污水(shui)處理、大(da)氣(qi)污染防治等(deng)(deng)領域,在治理環境污染方面越來越顯示出(chu)其(qi)(qi)誘人的(de)美好(hao)前景(jing)。
活性(xing)(xing)炭80%-90%以上由碳元(yuan)(yuan)素(su)組(zu)成,這也是(shi)活性(xing)(xing)炭為疏(shu)水(shui)性(xing)(xing)吸附劑的(de)原因。除(chu)了碳元(yuan)(yuan)素(su)外,還包含有兩(liang)類摻和物(wu):一類是(shi)化(hua)(hua)學結合的(de)元(yuan)(yuan)素(su),主要是(shi)氧和氫,這些元(yuan)(yuan)素(su)是(shi)由于未完全炭化(hua)(hua)而殘留在炭中(zhong),或者(zhe)在活化(hua)(hua)過程中(zhong),外來的(de)非(fei)碳元(yuan)(yuan)素(su)與活性(xing)(xing)炭表(biao)面(mian)化(hua)(hua)學結合,如用水(shui)蒸氣(qi)活化(hua)(hua)時(shi),活性(xing)(xing)炭表(biao)面(mian)被氧化(hua)(hua)或水(shui)蒸氣(qi)氧化(hua)(hua);另一類摻和物(wu)是(shi)灰分(fen)(fen),它是(shi)活性(xing)(xing)炭的(de)無(wu)機(ji)部分(fen)(fen)。
活(huo)性炭(tan)(tan)的(de)主(zhu)要原(yuan)料幾乎可以(yi)是(shi)(shi)所有(you)(you)富含(han)(han)碳(tan)(tan)的(de)有(you)(you)機(ji)材(cai)料,如煤、木(mu)材(cai)、果殼(ke)(ke)(ke)、椰(ye)殼(ke)(ke)(ke)、核桃(tao)殼(ke)(ke)(ke)、杏(xing)殼(ke)(ke)(ke)、棗殼(ke)(ke)(ke)等(deng)。這(zhe)(zhe)些含(han)(han)碳(tan)(tan)材(cai)料在(zai)(zai)活(huo)化爐中(zhong)(zhong),在(zai)(zai)高(gao)溫和(he)(he)一(yi)定壓力(li)下(xia)通(tong)過熱解作(zuo)(zuo)用(yong)被轉換成(cheng)活(huo)性炭(tan)(tan)。在(zai)(zai)此活(huo)化過程中(zhong)(zhong),巨大的(de)表(biao)面(mian)積和(he)(he)復(fu)雜的(de)孔(kong)隙結構逐(zhu)漸形成(cheng), 而(er)所謂的(de)吸(xi)(xi)附過程正是(shi)(shi)在(zai)(zai)這(zhe)(zhe)些孔(kong)隙中(zhong)(zhong)和(he)(he)表(biao)面(mian)上進行的(de),活(huo)性炭(tan)(tan)中(zhong)(zhong)孔(kong)隙的(de)大小(xiao)對(dui)吸(xi)(xi)附質有(you)(you)選擇(ze)吸(xi)(xi)附的(de)作(zuo)(zuo)用(yong),這(zhe)(zhe)是(shi)(shi)由于大分子不能(neng)進入比(bi)它孔(kong)隙小(xiao)的(de)活(huo)性炭(tan)(tan)孔(kong)徑內的(de)緣(yuan)故。活(huo)性炭(tan)(tan)是(shi)(shi)由含(han)(han)炭(tan)(tan)為(wei)主(zhu)的(de)物(wu)質作(zuo)(zuo)原(yuan)料,經高(gao)溫炭(tan)(tan)化和(he)(he)活(huo)化制得的(de)疏水(shui)性吸(xi)(xi)附劑。活(huo)性炭(tan)(tan)含(han)(han)有(you)(you)大量微(wei)孔(kong),具(ju)有(you)(you)巨大無比(bi)的(de)表(biao)面(mian)積,能(neng)有(you)(you)效地(di)去除(chu)色度、臭味,可去除(chu)二級出水(shui)中(zhong)(zhong)大多數有(you)(you)機(ji)污染(ran)物(wu)和(he)(he)某些無機(ji)物(wu),包(bao)含(han)(han)某些有(you)(you)毒(du)的(de)重金屬。