活性炭改性后處理(li)磺(huang)胺廢水

　　磺(huang)胺廢(fei)水經(jing)活(huo)(huo)性(xing)炭改(gai)性(xing)后(hou)處(chu)理，活(huo)(huo)性(xing)炭經(jing)氯(lv)化(hua)(hua)鐵(tie)改(gai)性(xing)。并進行批量(liang)(liang)實(shi)驗(yan)以(yi)評估廢(fei)水中的(de)磺(huang)胺二甲嘧啶(ding)吸附(fu)到(dao)活(huo)(huo)性(xing)炭和(he)改(gai)性(xing)活(huo)(huo)性(xing)炭上的(de)平(ping)衡，分別分析動力學(xue)和(he)熱力學(xue)特(te)征(zheng)。結果表(biao)明，氯(lv)化(hua)(hua)鐵(tie)處(chu)理后(hou)，活(huo)(huo)性(xing)炭改(gai)變(bian)了(le)表(biao)面(mian)(mian)積、孔隙(xi)體積和(he)表(biao)面(mian)(mian)zeta電(dian)位還(huan)增(zeng)加了(le)表(biao)面(mian)(mian)含(han)氧官(guan)能團的(de)數(shu)量(liang)(liang)。經(jing)試驗(yan)發現(xian)，磺(huang)胺二甲啶(ding)在(zai)改(gai)性(xing)活(huo)(huo)性(xing)炭上的(de)吸附(fu)得到(dao)了(le)顯著改(gai)善。

　　磺胺二甲啶是一種新型污染物，主要用于治療各種細菌感染引起的疾病。大多數磺胺二甲嘧啶以磺胺或代謝物的形式通過動物糞便和尿液釋放到環境中。這些磺胺或代謝物可能長期存在于環境中，可通過農場徑流和城市污水處理廠進入土壤、地表水、地下水甚至飲用水。傳統的污水處理技術只能去除廢水中的一些抗生素。這促使研究人員開發簡單高效的新技術，有效處理磺胺廢水。由于比表面積大，孔結構復雜，活性炭能(neng)有效去除顏色、氣味、無(wu)機(ji)化合物和(he)(he)大(da)多數(shu)有機(ji)污染物。但其(qi)(qi)(qi)在實(shi)際(ji)應用中(zhong)的(de)使用受(shou)其(qi)(qi)(qi)吸(xi)附(fu)(fu)(fu)效率和(he)(he)成本低的(de)限制。金屬離子改性(xing)(xing)(xing)(xing)后的(de)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)生產簡單(dan)便(bian)宜(yi)，能(neng)顯著(zhu)提(ti)高活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)吸(xi)附(fu)(fu)(fu)性(xing)(xing)(xing)(xing)能(neng)。然(ran)而，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)中(zhong)磺胺類廢水(shui)的(de)吸(xi)附(fu)(fu)(fu)機(ji)制尚不清楚，對磺胺類的(de)吸(xi)附(fu)(fu)(fu)能(neng)力及其(qi)(qi)(qi)理化性(xing)(xing)(xing)(xing)質知之甚少。本研究采用鐵離子改性(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)。用于(yu)探索吸(xi)附(fu)(fu)(fu)機(ji)制的(de)批量吸(xi)附(fu)(fu)(fu)實(shi)驗。磺胺二甲啶(ding)對活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)和(he)(he)改性(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)吸(xi)附(fu)(fu)(fu)特性(xing)(xing)(xing)(xing)通過吸(xi)附(fu)(fu)(fu)動力學、吸(xi)附(fu)(fu)(fu)熱力學和(he)(he)吸(xi)附(fu)(fu)(fu)等(deng)溫線(xian)進行了研究，為去除廢水(shui)中(zhong)的(de)磺胺污染物提(ti)供了科學依據(ju)。

　　活性炭改性后的特性

　　活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)化(hua)學結(jie)構(gou)和(he)(he)(he)物理化(hua)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異很(hen)大。鐵(tie)離(li)(li)子改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)后，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)表(biao)面(mian)(mian)(mian)(mian)積(ji)(ji)、總(zong)孔(kong)(kong)(kong)容量、微孔(kong)(kong)(kong)體積(ji)(ji)和(he)(he)(he)中(zhong)孔(kong)(kong)(kong)體積(ji)(ji)都有一(yi)(yi)(yi)定(ding)程度的(de)增(zeng)加(jia)，可以(yi)為磺胺二(er)甲(jia)啶提供(gong)更(geng)多的(de)吸(xi)(xi)附點(dian)。由于改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)微孔(kong)(kong)(kong)結(jie)構(gou)可能(neng)會產生較大的(de)比(bi)(bi)表(biao)面(mian)(mian)(mian)(mian)積(ji)(ji)。在(zai)活(huo)(huo)(huo)(huo)(huo)化(hua)過程中(zhong)，鐵(tie)離(li)(li)子主要沉積(ji)(ji)在(zai)介(jie)孔(kong)(kong)(kong)中(zhong)，擴大孔(kong)(kong)(kong)徑并(bing)進(jin)入(ru)微孔(kong)(kong)(kong)。將(jiang)金屬鹽釋放的(de)氧(yang)化(hua)氣體引入(ru)微孔(kong)(kong)(kong)，并(bing)與(yu)微孔(kong)(kong)(kong)碳(tan)(tan)壁反(fan)應。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)SEM圖(tu)1顯(xian)示(shi)圖(tu)像(xiang)(a)和(he)(he)(he)(b)中(zhong)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)形狀表(biao)明(ming)(ming)(ming)(ming)具有規(gui)則孔(kong)(kong)(kong)結(jie)構(gou)的(de)光(guang)滑表(biao)面(mian)(mian)(mian)(mian)。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)相(xiang)比(bi)(bi)，改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)表(biao)面(mian)(mian)(mian)(mian)粗糙(cao)不規(gui)則。孔(kong)(kong)(kong)隙(xi)結(jie)構(gou)受損(sun)，孔(kong)(kong)(kong)隙(xi)率增(zeng)加(jia)。這(zhe)(zhe)可能(neng)是由于鐵(tie)離(li)(li)子引入(ru)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)內孔(kong)(kong)(kong)，導致碳(tan)(tan)壁氧(yang)化(hua)和(he)(he)(he)孔(kong)(kong)(kong)徑增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)中(zhong)磺胺二(er)甲(jia)啶的(de)擴散有利于粗糙(cao)的(de)表(biao)面(mian)(mian)(mian)(mian)結(jie)構(gou)和(he)(he)(he)多孔(kong)(kong)(kong)特性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)TEM圖(tu)像(xiang)如圖(tu)1(c)和(he)(he)(he)(d)所示(shi)。這(zhe)(zhe)些圖(tu)片表(biao)明(ming)(ming)(ming)(ming)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)是無定(ding)形的(de)。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)相(xiang)比(bi)(bi)，改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)表(biao)現出許多孔(kong)(kong)(kong)隙(xi)和(he)(he)(he)透明(ming)(ming)(ming)(ming)點(dian)，進(jin)一(yi)(yi)(yi)步(bu)表(biao)明(ming)(ming)(ming)(ming)表(biao)面(mian)(mian)(mian)(mian)積(ji)(ji)增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)EDS圖(tu)像(xiang)如圖(tu)1(e)和(he)(he)(he)(f)所示(shi)。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)相(xiang)比(bi)(bi)，改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)元(yuan)素O和(he)(he)(he)Fe含量顯(xian)著(zhu)增(zeng)加(jia)，C活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)上鐵(tie)離(li)(li)子負荷的(de)含量降(jiang)低。此外，進(jin)一(yi)(yi)(yi)步(bu)證明(ming)(ming)(ming)(ming)表(biao)面(mian)(mian)(mian)(mian)含氧(yang)量增(zeng)加(jia)，有利于磺胺二(er)甲(jia)啶的(de)吸(xi)(xi)附。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)XRD圖(tu)如圖(tu)1(g)和(he)(he)(he)(h)所示(shi)。而且沒有活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)(gai)(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)的(de)明(ming)(ming)(ming)(ming)顯(xian)特征峰值，說明(ming)(ming)(ming)(ming)它們(men)是無形的(de)。這(zhe)(zhe)與(yu)TEM照片結(jie)果(guo)一(yi)(yi)(yi)致。

　　兩種吸(xi)附劑的(de)代表(biao)性(xing)(xing)(xing)SEM，TEM和(he)EDS圖像。(a)活(huo)性(xing)(xing)(xing)炭的(de)SEM(比(bi)例(li)尺(chi)為(wei)2μm)，(b)活(huo)性(xing)(xing)(xing)炭的(de)TEM(比(bi)例(li)尺(chi)為(wei)100nm)，(c)活(huo)性(xing)(xing)(xing)炭的(de)EDS，(d)改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭SEM(比(bi)例(li)尺(chi)為(wei)2μm)，(e)改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭TEM(比(bi)例(li)尺(chi)為(wei)100nm)，(f)改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭EDS，(g)活(huo)性(xing)(xing)(xing)炭的(de)XRD，(h)改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭XRD。

　　活(huo)性炭吸附磺(huang)胺的三(san)個(ge)階段

　　活性(xing)(xing)(xing)炭(tan)和改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)和改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)上(shang)的(de)(de)吸附(fu)(fu)(fu)和擴散過程(cheng)(cheng)可(ke)分三個(ge)階(jie)(jie)段描述，如圖2所(suo)示。由于**階(jie)(jie)段吸附(fu)(fu)(fu)在(zai)活性(xing)(xing)(xing)炭(tan)表面，吸附(fu)(fu)(fu)率(lv)(lv)*初(chu)很高。然后，在(zai)顆粒(li)(li)內快(kuai)速(su)擴散的(de)(de)過程(cheng)(cheng)中，磺胺二甲啶逐(zhu)漸吸附(fu)(fu)(fu)在(zai)活性(xing)(xing)(xing)炭(tan)上(shang)，吸附(fu)(fu)(fu)率(lv)(lv)常(chang)數逐(zhu)漸降低(di)。在(zai)第三階(jie)(jie)段，邊界層(ceng)和傳質阻力的(de)(de)影響增加，導致(zhi)顆粒(li)(li)擴散減慢(man)。所(suo)有三個(ge)階(jie)(jie)段的(de)(de)擬合方(fang)程(cheng)(cheng)都沒有通過坐標的(de)(de)原點，這表明顆粒(li)(li)的(de)(de)擴散并不是(shi)控制吸附(fu)(fu)(fu)率(lv)(lv)的(de)(de)**步(bu)驟。因此(ci)，吸附(fu)(fu)(fu)過程(cheng)(cheng)也受膜擴散和表面吸附(fu)(fu)(fu)的(de)(de)影響。

　　磺胺二甲啶在(zai)活性炭上(shang)吸附的顆(ke)粒(li)中擴散。

　　改(gai)性(xing)(xing)活(huo)性(xing)(xing)炭(tan)的(de)表面顯示(shi)出(chu)許(xu)多孔隙(xi)和透明(ming)度，大量含氧官(guan)能(neng)團被改(gai)性(xing)(xing)，導(dao)致磺胺二甲(jia)啶(ding)吸附(fu)機制的(de)變化。根據本研究(jiu)的(de)相(xiang)關研究(jiu)結果，活(huo)性(xing)(xing)炭(tan)表面磺胺二甲(jia)啶(ding)的(de)吸附(fu)機制總結如下（圖3）：

　　1.微孔捕獲

　　SEM圖像顯示(shi)，活性(xing)炭的規則孔結構(gou)受損，孔隙率增(zeng)加。TEM圖像顯示(shi)，改性(xing)活性(xing)炭表面(mian)含有許(xu)多(duo)透明點，表明孔結構(gou)更發達，修改后可(ke)獲得更多(duo)的吸附(fu)點。這(zhe)有利(li)于磺胺二甲啶吸附(fu)到黑碳分(fen)子層(ceng)的孔中(zhong)。此外，經(jing)鐵離子改性(xing)后，活性(xing)炭的表面(mian)積、總孔容量、微孔體積和中(zhong)孔體積都有一定程(cheng)度的增(zeng)加。

　　2.氫鍵相互作用

　　通過FTIR通過促進改性活(huo)性炭(tan)(tan)表(biao)(biao)面與(yu)磺胺(an)(an)二甲(jia)啶(ding)之(zhi)間(jian)氫鍵的(de)相(xiang)互作用，促進磺胺(an)(an)二甲(jia)啶(ding)的(de)吸附。從(cong)數據圖中發(fa)現，3400和2850cm-1處寬(kuan)吸收峰(feng)表(biao)(biao)明改性活(huo)性炭(tan)(tan)表(biao)(biao)面存在-OH。這些分子間(jian)氫鍵增(zeng)強(qiang)了(le)磺胺(an)(an)二甲(jia)啶(ding)與(yu)活(huo)性炭(tan)(tan)的(de)表(biao)(biao)面相(xiang)互作用，預計將有助于活(huo)性炭(tan)(tan)與(yu)異磺胺(an)(an)二甲(jia)啶(ding)之(zhi)間(jian)的(de)親和力(li)吸附。

　　3.π-π電(dian)子供體-受(shou)體(EDA)相(xiang)互(hu)作(zuo)用。

　　磺胺二甲啶與改性活性炭合理(li)相(xiang)(xiang)互(hu)作(zuo)(zuo)(zuo)用(yong)的示意(yi)圖。1.微孔捕(bu)獲。2.氫鍵相(xiang)(xiang)互(hu)作(zuo)(zuo)(zuo)用(yong)。.π-πEDA相(xiang)(xiang)互(hu)作(zuo)(zuo)(zuo)用(yong)。4.靜電相(xiang)(xiang)互(hu)作(zuo)(zuo)(zuo)用(yong)。5.配位(wei)相(xiang)(xiang)互(hu)作(zuo)(zuo)(zuo)用(yong)。

　　鐵離子改性(xing)(xing)后，活(huo)(huo)(huo)性(xing)(xing)炭(tan)活(huo)(huo)(huo)性(xing)(xing)炭(tan)的(de)(de)表(biao)面積(ji)、總孔容量(liang)、微(wei)孔體積(ji)和中孔體積(ji)。含(han)氧加(jia)(jia)了活(huo)(huo)(huo)性(xing)(xing)炭(tan)表(biao)面含(han)氧官能(neng)團的(de)(de)數量(liang)，可以大(da)大(da)提高吸(xi)(xi)(xi)附(fu)(fu)(fu)能(neng)力(li)。磺(huang)(huang)胺(an)二(er)(er)甲(jia)嘧啶(ding)(ding)(ding)(ding)在(zai)改性(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)炭(tan)上去除磺(huang)(huang)胺(an)廢(fei)水中顯著(zhu)增(zeng)加(jia)(jia)，并在(zai)25℃下磺(huang)(huang)胺(an)二(er)(er)甲(jia)嘧啶(ding)(ding)(ding)(ding)在(zai)改性(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)炭(tan)上的(de)(de)*大(da)吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)為(wei)17.261mg/g。然(ran)而，吸(xi)(xi)(xi)附(fu)(fu)(fu)平衡時間(jian)幾乎保持不變。磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)在(zai)原始和改性(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)炭(tan)上的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)動力(li)學分為(wei)快速和慢速吸(xi)(xi)(xi)附(fu)(fu)(fu)階段，磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)吸(xi)(xi)(xi)附(fu)(fu)(fu)在(zai)12小時內快速完(wan)成(cheng)。pH該值對磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)有顯著(zhu)影響。當pH磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)在(zai)3-10之間(jian)增(zeng)加(jia)(jia)，然(ran)后減(jian)少。微(wei)孔捕獲，靜電相互作(zuo)(zuo)用(yong)，氫鍵相互作(zuo)(zuo)用(yong)，π-πEDA相互作(zuo)(zuo)用(yong)和配位相互作(zuo)(zuo)用(yong)是(shi)吸(xi)(xi)(xi)附(fu)(fu)(fu)的(de)(de)可能(neng)機(ji)制。降低溫度促進(jin)吸(xi)(xi)(xi)附(fu)(fu)(fu)反應。pH該值對磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)有顯著(zhu)影響。當pH磺(huang)(huang)胺(an)二(er)(er)甲(jia)啶(ding)(ding)(ding)(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)在(zai)3-10之間(jian)增(zeng)加(jia)(jia)，然(ran)后減(jian)少。