活性(xing)炭改性(xing)后處(chu)理(li)磺胺(an)廢水

　　磺胺廢水經活(huo)性(xing)(xing)炭(tan)改(gai)性(xing)(xing)后(hou)處理(li)，活(huo)性(xing)(xing)炭(tan)經氯(lv)化鐵(tie)改(gai)性(xing)(xing)。并進行(xing)批量實驗以(yi)評估廢水中的(de)磺胺二甲嘧啶吸(xi)附(fu)(fu)到(dao)活(huo)性(xing)(xing)炭(tan)和(he)(he)改(gai)性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上的(de)平衡(heng)，分別分析動力(li)學和(he)(he)熱(re)力(li)學特征。結果表(biao)(biao)(biao)明，氯(lv)化鐵(tie)處理(li)后(hou)，活(huo)性(xing)(xing)炭(tan)改(gai)變了(le)表(biao)(biao)(biao)面積、孔隙體積和(he)(he)表(biao)(biao)(biao)面zeta電位還增加了(le)表(biao)(biao)(biao)面含氧(yang)官能(neng)團的(de)數量。經試(shi)驗發現，磺胺二甲啶在改(gai)性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上的(de)吸(xi)附(fu)(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，活性炭能有效去除顏色、氣味、無(wu)機(ji)化(hua)(hua)合物(wu)和大(da)多數(shu)有機(ji)污染物(wu)。但其(qi)(qi)在(zai)實際應用(yong)中(zhong)的使用(yong)受其(qi)(qi)吸(xi)(xi)(xi)附(fu)效率和成本(ben)低的限(xian)制。金屬離子(zi)改性(xing)(xing)(xing)(xing)(xing)后(hou)的活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭生產簡(jian)單(dan)便(bian)宜(yi)，能顯(xian)著(zhu)提高活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭的吸(xi)(xi)(xi)附(fu)性(xing)(xing)(xing)(xing)(xing)能。然(ran)而，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭中(zhong)磺胺(an)類廢水的吸(xi)(xi)(xi)附(fu)機(ji)制尚不清楚，對(dui)磺胺(an)類的吸(xi)(xi)(xi)附(fu)能力(li)(li)及其(qi)(qi)理(li)化(hua)(hua)性(xing)(xing)(xing)(xing)(xing)質知之甚(shen)少。本(ben)研究采用(yong)鐵離子(zi)改性(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭。用(yong)于探索吸(xi)(xi)(xi)附(fu)機(ji)制的批量吸(xi)(xi)(xi)附(fu)實驗。磺胺(an)二甲啶對(dui)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭和改性(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)炭的吸(xi)(xi)(xi)附(fu)特(te)性(xing)(xing)(xing)(xing)(xing)通過吸(xi)(xi)(xi)附(fu)動力(li)(li)學(xue)、吸(xi)(xi)(xi)附(fu)熱力(li)(li)學(xue)和吸(xi)(xi)(xi)附(fu)等溫線進(jin)行了研究，為去除廢水中(zhong)的磺胺(an)污染物(wu)提供了科(ke)學(xue)依據。

　　活性炭改(gai)性后的特性

　　活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)化(hua)學(xue)結(jie)構和(he)(he)物理化(hua)學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異很大(da)。鐵(tie)(tie)(tie)離(li)子改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)后，活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)表面(mian)積(ji)(ji)、總孔(kong)(kong)(kong)容量、微孔(kong)(kong)(kong)體積(ji)(ji)和(he)(he)中(zhong)孔(kong)(kong)(kong)體積(ji)(ji)都(dou)有一(yi)定程度的(de)(de)增(zeng)(zeng)加(jia)，可(ke)以(yi)為磺胺二(er)甲啶提(ti)供更多(duo)的(de)(de)吸附(fu)點。由于(yu)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)，活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)微孔(kong)(kong)(kong)結(jie)構可(ke)能會產生較大(da)的(de)(de)比表面(mian)積(ji)(ji)。在活(huo)(huo)(huo)(huo)(huo)(huo)(huo)化(hua)過(guo)程中(zhong)，鐵(tie)(tie)(tie)離(li)子主要沉積(ji)(ji)在介孔(kong)(kong)(kong)中(zhong)，擴大(da)孔(kong)(kong)(kong)徑并進(jin)入微孔(kong)(kong)(kong)。將金屬鹽(yan)釋放的(de)(de)氧(yang)(yang)(yang)化(hua)氣體引入微孔(kong)(kong)(kong)，并與微孔(kong)(kong)(kong)碳壁反應。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)SEM圖(tu)(tu)1顯示圖(tu)(tu)像(a)和(he)(he)(b)中(zhong)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)形狀表明(ming)具有規(gui)則(ze)(ze)孔(kong)(kong)(kong)結(jie)構的(de)(de)光滑表面(mian)。與活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)表面(mian)粗糙不規(gui)則(ze)(ze)。孔(kong)(kong)(kong)隙結(jie)構受(shou)損，孔(kong)(kong)(kong)隙率增(zeng)(zeng)加(jia)。這(zhe)可(ke)能是由于(yu)鐵(tie)(tie)(tie)離(li)子引入活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)內(nei)孔(kong)(kong)(kong)，導致碳壁氧(yang)(yang)(yang)化(hua)和(he)(he)孔(kong)(kong)(kong)徑增(zeng)(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)中(zhong)磺胺二(er)甲啶的(de)(de)擴散有利于(yu)粗糙的(de)(de)表面(mian)結(jie)構和(he)(he)多(duo)孔(kong)(kong)(kong)特性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)TEM圖(tu)(tu)像如圖(tu)(tu)1(c)和(he)(he)(d)所(suo)示。這(zhe)些(xie)圖(tu)(tu)片(pian)表明(ming)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)是無定形的(de)(de)。與活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)表現出許多(duo)孔(kong)(kong)(kong)隙和(he)(he)透明(ming)點，進(jin)一(yi)步表明(ming)表面(mian)積(ji)(ji)增(zeng)(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)EDS圖(tu)(tu)像如圖(tu)(tu)1(e)和(he)(he)(f)所(suo)示。與活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)元素O和(he)(he)Fe含量顯著增(zeng)(zeng)加(jia)，C活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)上鐵(tie)(tie)(tie)離(li)子負荷(he)的(de)(de)含量降低。此(ci)外，進(jin)一(yi)步證明(ming)表面(mian)含氧(yang)(yang)(yang)量增(zeng)(zeng)加(jia)，有利于(yu)磺胺二(er)甲啶的(de)(de)吸附(fu)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)XRD圖(tu)(tu)如圖(tu)(tu)1(g)和(he)(he)(h)所(suo)示。而(er)且(qie)沒有活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)和(he)(he)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)(tan)(tan)(tan)的(de)(de)明(ming)顯特征(zheng)峰值，說明(ming)它們(men)是無形的(de)(de)。這(zhe)與TEM照片(pian)結(jie)果(guo)一(yi)致。

　　兩(liang)種吸(xi)附劑的(de)代(dai)表(biao)性(xing)(xing)(xing)SEM，TEM和(he)EDS圖像。(a)活(huo)(huo)性(xing)(xing)(xing)炭(tan)的(de)SEM(比例(li)尺為2μm)，(b)活(huo)(huo)性(xing)(xing)(xing)炭(tan)的(de)TEM(比例(li)尺為100nm)，(c)活(huo)(huo)性(xing)(xing)(xing)炭(tan)的(de)EDS，(d)改(gai)(gai)性(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)炭(tan)SEM(比例(li)尺為2μm)，(e)改(gai)(gai)性(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)炭(tan)TEM(比例(li)尺為100nm)，(f)改(gai)(gai)性(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)炭(tan)EDS，(g)活(huo)(huo)性(xing)(xing)(xing)炭(tan)的(de)XRD，(h)改(gai)(gai)性(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)炭(tan)XRD。

　　活(huo)性(xing)炭吸附磺(huang)胺的三(san)個(ge)階段(duan)

　　活性(xing)(xing)炭(tan)和(he)改(gai)性(xing)(xing)活性(xing)(xing)炭(tan)和(he)改(gai)性(xing)(xing)活性(xing)(xing)炭(tan)上的(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)和(he)擴散(san)(san)過(guo)程(cheng)可(ke)分三個階(jie)段(duan)(duan)描(miao)述，如圖2所(suo)示。由于**階(jie)段(duan)(duan)吸(xi)(xi)(xi)附(fu)(fu)(fu)在(zai)(zai)(zai)活性(xing)(xing)炭(tan)表面，吸(xi)(xi)(xi)附(fu)(fu)(fu)率*初很(hen)高(gao)。然后，在(zai)(zai)(zai)顆(ke)粒內快速擴散(san)(san)的(de)過(guo)程(cheng)中，磺胺二(er)甲啶(ding)逐漸吸(xi)(xi)(xi)附(fu)(fu)(fu)在(zai)(zai)(zai)活性(xing)(xing)炭(tan)上，吸(xi)(xi)(xi)附(fu)(fu)(fu)率常數逐漸降低。在(zai)(zai)(zai)第三階(jie)段(duan)(duan)，邊界(jie)層和(he)傳質阻(zu)力的(de)影響增加，導致顆(ke)粒擴散(san)(san)減慢。所(suo)有三個階(jie)段(duan)(duan)的(de)擬(ni)合方程(cheng)都(dou)沒有通過(guo)坐標的(de)原點，這表明(ming)顆(ke)粒的(de)擴散(san)(san)并不是控(kong)制(zhi)吸(xi)(xi)(xi)附(fu)(fu)(fu)率的(de)**步驟。因此，吸(xi)(xi)(xi)附(fu)(fu)(fu)過(guo)程(cheng)也受膜擴散(san)(san)和(he)表面吸(xi)(xi)(xi)附(fu)(fu)(fu)的(de)影響。

　　磺胺(an)二甲啶(ding)在活性(xing)炭上(shang)吸附(fu)的顆粒中擴散。

　　改(gai)性(xing)活性(xing)炭的(de)(de)表面顯示出許多孔隙和透(tou)明度，大量含(han)氧(yang)官(guan)能團(tuan)被改(gai)性(xing)，導(dao)致磺胺(an)二甲啶吸附機制的(de)(de)變化。根據本研究的(de)(de)相關研究結(jie)果，活性(xing)炭表面磺胺(an)二甲啶的(de)(de)吸附機制總結(jie)如(ru)下（圖(tu)3）：

　　1.微孔捕獲

　　SEM圖(tu)像(xiang)顯(xian)示(shi)，活性(xing)(xing)炭的規(gui)則孔(kong)結構(gou)受損，孔(kong)隙率增加。TEM圖(tu)像(xiang)顯(xian)示(shi)，改(gai)性(xing)(xing)活性(xing)(xing)炭表面含有(you)許(xu)多透(tou)明點，表明孔(kong)結構(gou)更(geng)發達，修改(gai)后可(ke)獲(huo)得更(geng)多的吸附點。這有(you)利(li)于磺胺二甲啶吸附到黑碳分子層的孔(kong)中。此外，經(jing)鐵(tie)離子改(gai)性(xing)(xing)后，活性(xing)(xing)炭的表面積、總孔(kong)容量、微孔(kong)體積和中孔(kong)體積都有(you)一定(ding)程度(du)的增加。

　　2.氫鍵相互作(zuo)用(yong)

　　通過(guo)FTIR通過(guo)促(cu)進(jin)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)(tan)表面與磺(huang)胺二甲(jia)啶之(zhi)間(jian)氫(qing)鍵(jian)的(de)(de)相互作(zuo)用，促(cu)進(jin)磺(huang)胺二甲(jia)啶的(de)(de)吸附。從(cong)數據(ju)圖中發現，3400和(he)2850cm-1處(chu)寬吸收峰表明改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)(tan)表面存在-OH。這些分子(zi)間(jian)氫(qing)鍵(jian)增強(qiang)了(le)磺(huang)胺二甲(jia)啶與活(huo)性(xing)(xing)炭(tan)(tan)的(de)(de)表面相互作(zuo)用，預計將有(you)助于活(huo)性(xing)(xing)炭(tan)(tan)與異磺(huang)胺二甲(jia)啶之(zhi)間(jian)的(de)(de)親和(he)力吸附。

　　3.π-π電子供體-受體(EDA)相互作用。

　　磺胺二甲啶與改(gai)性活(huo)性炭合理相互作(zuo)用(yong)的示意圖。1.微(wei)孔捕獲。2.氫鍵相互作(zuo)用(yong)。.π-πEDA相互作(zuo)用(yong)。4.靜(jing)電(dian)相互作(zuo)用(yong)。5.配位相互作(zuo)用(yong)。

　　鐵離子改(gai)(gai)性(xing)(xing)后(hou)(hou)，活性(xing)(xing)炭活性(xing)(xing)炭的表面積、總孔(kong)容量、微孔(kong)體積和(he)中孔(kong)體積。含氧加(jia)了活性(xing)(xing)炭表面含氧官能(neng)(neng)團的數量，可(ke)以大(da)大(da)提高吸附(fu)(fu)能(neng)(neng)力(li)。磺(huang)(huang)(huang)胺(an)二(er)甲(jia)嘧啶在(zai)(zai)改(gai)(gai)性(xing)(xing)活性(xing)(xing)炭上(shang)去除磺(huang)(huang)(huang)胺(an)廢(fei)水中顯(xian)著(zhu)增(zeng)加(jia)，并在(zai)(zai)25℃下磺(huang)(huang)(huang)胺(an)二(er)甲(jia)嘧啶在(zai)(zai)改(gai)(gai)性(xing)(xing)活性(xing)(xing)炭上(shang)的*大(da)吸附(fu)(fu)量為17.261mg/g。然(ran)而(er)，吸附(fu)(fu)平衡時間幾乎保持不變。磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶在(zai)(zai)原始和(he)改(gai)(gai)性(xing)(xing)活性(xing)(xing)炭上(shang)的吸附(fu)(fu)動力(li)學分為快(kuai)速和(he)慢速吸附(fu)(fu)階段(duan)，磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶吸附(fu)(fu)在(zai)(zai)12小時內(nei)快(kuai)速完成。pH該值對磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶的吸附(fu)(fu)有顯(xian)著(zhu)影響(xiang)。當pH磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶的吸附(fu)(fu)量在(zai)(zai)3-10之(zhi)間增(zeng)加(jia)，然(ran)后(hou)(hou)減少(shao)。微孔(kong)捕獲，靜電相(xiang)(xiang)互作用(yong)(yong)，氫鍵相(xiang)(xiang)互作用(yong)(yong)，π-πEDA相(xiang)(xiang)互作用(yong)(yong)和(he)配位(wei)相(xiang)(xiang)互作用(yong)(yong)是吸附(fu)(fu)的可(ke)能(neng)(neng)機制。降低(di)溫度促進吸附(fu)(fu)反應。pH該值對磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶的吸附(fu)(fu)有顯(xian)著(zhu)影響(xiang)。當pH磺(huang)(huang)(huang)胺(an)二(er)甲(jia)啶的吸附(fu)(fu)量在(zai)(zai)3-10之(zhi)間增(zeng)加(jia)，然(ran)后(hou)(hou)減少(shao)。