活(huo)性炭改性后(hou)處理磺(huang)胺廢(fei)水

　　磺胺(an)廢(fei)水(shui)經活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)改性(xing)(xing)(xing)(xing)后(hou)處(chu)理(li)(li)，活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)經氯化(hua)(hua)鐵(tie)改性(xing)(xing)(xing)(xing)。并進(jin)行批量實驗以(yi)評估廢(fei)水(shui)中的磺胺(an)二(er)甲(jia)嘧啶吸附(fu)到(dao)(dao)活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)和(he)改性(xing)(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)上(shang)(shang)的平衡(heng)，分別(bie)分析動力(li)學(xue)和(he)熱力(li)學(xue)特(te)征。結(jie)果表(biao)明，氯化(hua)(hua)鐵(tie)處(chu)理(li)(li)后(hou)，活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)改變(bian)了表(biao)面(mian)積(ji)、孔隙(xi)體積(ji)和(he)表(biao)面(mian)zeta電位還增(zeng)加了表(biao)面(mian)含(han)氧官能團的數量。經試驗發現，磺胺(an)二(er)甲(jia)啶在改性(xing)(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)上(shang)(shang)的吸附(fu)得到(dao)(dao)了顯(xian)著改善。

　　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(you)效去(qu)除(chu)顏色、氣味、無(wu)機(ji)化(hua)合物和(he)大多(duo)數有(you)機(ji)污染(ran)物。但其(qi)在實(shi)際應用(yong)(yong)中(zhong)(zhong)的(de)(de)(de)(de)使用(yong)(yong)受其(qi)吸(xi)(xi)(xi)(xi)附(fu)效率和(he)成本(ben)低的(de)(de)(de)(de)限制(zhi)。金屬(shu)離子(zi)改性(xing)(xing)后(hou)的(de)(de)(de)(de)活(huo)(huo)性(xing)(xing)炭生產簡單便宜，能顯著提高活(huo)(huo)性(xing)(xing)炭的(de)(de)(de)(de)吸(xi)(xi)(xi)(xi)附(fu)性(xing)(xing)能。然(ran)而(er)，活(huo)(huo)性(xing)(xing)炭中(zhong)(zhong)磺胺(an)類(lei)廢水的(de)(de)(de)(de)吸(xi)(xi)(xi)(xi)附(fu)機(ji)制(zhi)尚不清楚，對(dui)磺胺(an)類(lei)的(de)(de)(de)(de)吸(xi)(xi)(xi)(xi)附(fu)能力及其(qi)理化(hua)性(xing)(xing)質知之甚(shen)少。本(ben)研究采用(yong)(yong)鐵離子(zi)改性(xing)(xing)活(huo)(huo)性(xing)(xing)炭。用(yong)(yong)于探(tan)索吸(xi)(xi)(xi)(xi)附(fu)機(ji)制(zhi)的(de)(de)(de)(de)批量(liang)吸(xi)(xi)(xi)(xi)附(fu)實(shi)驗(yan)。磺胺(an)二甲啶對(dui)活(huo)(huo)性(xing)(xing)炭和(he)改性(xing)(xing)活(huo)(huo)性(xing)(xing)炭的(de)(de)(de)(de)吸(xi)(xi)(xi)(xi)附(fu)特(te)性(xing)(xing)通過吸(xi)(xi)(xi)(xi)附(fu)動力學、吸(xi)(xi)(xi)(xi)附(fu)熱力學和(he)吸(xi)(xi)(xi)(xi)附(fu)等溫線進行(xing)了研究，為(wei)去(qu)除(chu)廢水中(zhong)(zhong)的(de)(de)(de)(de)磺胺(an)污染(ran)物提供了科學依據(ju)。

　　活(huo)性(xing)炭改性(xing)后的(de)特性(xing)

　　活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)化(hua)學(xue)結(jie)(jie)構和(he)(he)(he)物理(li)化(hua)學(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異很(hen)大(da)。鐵(tie)(tie)離(li)(li)子(zi)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)后，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)表(biao)(biao)(biao)面積、總孔(kong)(kong)(kong)(kong)(kong)容量(liang)、微孔(kong)(kong)(kong)(kong)(kong)體積和(he)(he)(he)中(zhong)孔(kong)(kong)(kong)(kong)(kong)體積都有(you)一(yi)定程(cheng)(cheng)度的(de)(de)(de)(de)(de)增(zeng)加(jia)，可以(yi)為磺胺二(er)甲啶提供更(geng)多(duo)的(de)(de)(de)(de)(de)吸附(fu)點。由于改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)微孔(kong)(kong)(kong)(kong)(kong)結(jie)(jie)構可能(neng)會產生較大(da)的(de)(de)(de)(de)(de)比(bi)(bi)(bi)(bi)表(biao)(biao)(biao)面積。在活(huo)(huo)(huo)(huo)(huo)化(hua)過(guo)程(cheng)(cheng)中(zhong)，鐵(tie)(tie)離(li)(li)子(zi)主要沉積在介孔(kong)(kong)(kong)(kong)(kong)中(zhong)，擴大(da)孔(kong)(kong)(kong)(kong)(kong)徑并進入(ru)微孔(kong)(kong)(kong)(kong)(kong)。將金屬鹽釋放的(de)(de)(de)(de)(de)氧(yang)化(hua)氣體引入(ru)微孔(kong)(kong)(kong)(kong)(kong)，并與(yu)微孔(kong)(kong)(kong)(kong)(kong)碳壁(bi)反應。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)SEM圖(tu)1顯(xian)示(shi)(shi)圖(tu)像(a)和(he)(he)(he)(b)中(zhong)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)形(xing)狀表(biao)(biao)(biao)明(ming)具有(you)規則孔(kong)(kong)(kong)(kong)(kong)結(jie)(jie)構的(de)(de)(de)(de)(de)光滑表(biao)(biao)(biao)面。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比(bi)(bi)(bi)(bi)，改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)(biao)(biao)面粗糙不規則。孔(kong)(kong)(kong)(kong)(kong)隙結(jie)(jie)構受損，孔(kong)(kong)(kong)(kong)(kong)隙率增(zeng)加(jia)。這(zhe)可能(neng)是(shi)由于鐵(tie)(tie)離(li)(li)子(zi)引入(ru)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)內孔(kong)(kong)(kong)(kong)(kong)，導致碳壁(bi)氧(yang)化(hua)和(he)(he)(he)孔(kong)(kong)(kong)(kong)(kong)徑增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)中(zhong)磺胺二(er)甲啶的(de)(de)(de)(de)(de)擴散有(you)利于粗糙的(de)(de)(de)(de)(de)表(biao)(biao)(biao)面結(jie)(jie)構和(he)(he)(he)多(duo)孔(kong)(kong)(kong)(kong)(kong)特(te)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)TEM圖(tu)像如圖(tu)1(c)和(he)(he)(he)(d)所示(shi)(shi)。這(zhe)些圖(tu)片表(biao)(biao)(biao)明(ming)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)是(shi)無(wu)定形(xing)的(de)(de)(de)(de)(de)。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比(bi)(bi)(bi)(bi)，改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)(biao)(biao)現出許(xu)多(duo)孔(kong)(kong)(kong)(kong)(kong)隙和(he)(he)(he)透(tou)明(ming)點，進一(yi)步表(biao)(biao)(biao)明(ming)表(biao)(biao)(biao)面積增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)EDS圖(tu)像如圖(tu)1(e)和(he)(he)(he)(f)所示(shi)(shi)。與(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比(bi)(bi)(bi)(bi)，改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)元素O和(he)(he)(he)Fe含量(liang)顯(xian)著增(zeng)加(jia)，C活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)上(shang)鐵(tie)(tie)離(li)(li)子(zi)負荷的(de)(de)(de)(de)(de)含量(liang)降低。此外(wai)，進一(yi)步證明(ming)表(biao)(biao)(biao)面含氧(yang)量(liang)增(zeng)加(jia)，有(you)利于磺胺二(er)甲啶的(de)(de)(de)(de)(de)吸附(fu)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)XRD圖(tu)如圖(tu)1(g)和(he)(he)(he)(h)所示(shi)(shi)。而且(qie)沒有(you)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)(he)改(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)(de)明(ming)顯(xian)特(te)征(zheng)峰值，說明(ming)它們是(shi)無(wu)形(xing)的(de)(de)(de)(de)(de)。這(zhe)與(yu)TEM照片結(jie)(jie)果一(yi)致。

　　兩種吸附劑的代表性(xing)SEM，TEM和EDS圖像。(a)活(huo)(huo)性(xing)炭(tan)(tan)(tan)的SEM(比例尺(chi)為2μm)，(b)活(huo)(huo)性(xing)炭(tan)(tan)(tan)的TEM(比例尺(chi)為100nm)，(c)活(huo)(huo)性(xing)炭(tan)(tan)(tan)的EDS，(d)改(gai)(gai)性(xing)活(huo)(huo)性(xing)炭(tan)(tan)(tan)SEM(比例尺(chi)為2μm)，(e)改(gai)(gai)性(xing)活(huo)(huo)性(xing)炭(tan)(tan)(tan)TEM(比例尺(chi)為100nm)，(f)改(gai)(gai)性(xing)活(huo)(huo)性(xing)炭(tan)(tan)(tan)EDS，(g)活(huo)(huo)性(xing)炭(tan)(tan)(tan)的XRD，(h)改(gai)(gai)性(xing)活(huo)(huo)性(xing)炭(tan)(tan)(tan)XRD。

　　活性炭吸(xi)附磺胺的三個階(jie)段

　　活(huo)性炭(tan)和(he)改(gai)性活(huo)性炭(tan)和(he)改(gai)性活(huo)性炭(tan)上(shang)(shang)的(de)(de)吸附(fu)和(he)擴散(san)(san)過(guo)程可分三(san)(san)個階(jie)段(duan)描(miao)述，如圖2所(suo)示。由于**階(jie)段(duan)吸附(fu)在(zai)活(huo)性炭(tan)表面，吸附(fu)率*初很高(gao)。然后，在(zai)顆粒內快速擴散(san)(san)的(de)(de)過(guo)程中(zhong)，磺胺二(er)甲啶逐(zhu)漸(jian)吸附(fu)在(zai)活(huo)性炭(tan)上(shang)(shang)，吸附(fu)率常數逐(zhu)漸(jian)降低(di)。在(zai)第三(san)(san)階(jie)段(duan)，邊界層和(he)傳質阻力的(de)(de)影響(xiang)增加，導致顆粒擴散(san)(san)減(jian)慢。所(suo)有(you)三(san)(san)個階(jie)段(duan)的(de)(de)擬合方程都(dou)沒有(you)通過(guo)坐標的(de)(de)原點，這表明顆粒的(de)(de)擴散(san)(san)并不是控(kong)制吸附(fu)率的(de)(de)**步驟。因此，吸附(fu)過(guo)程也受(shou)膜擴散(san)(san)和(he)表面吸附(fu)的(de)(de)影響(xiang)。

　　磺胺(an)二甲啶在活(huo)性炭上吸附的(de)顆粒(li)中擴(kuo)散。

　　改性活性炭(tan)的(de)(de)表(biao)面顯示(shi)出許多孔隙(xi)和透明度，大量含氧(yang)官能(neng)團(tuan)被改性，導(dao)致磺(huang)(huang)胺(an)二甲(jia)啶(ding)吸(xi)附機制的(de)(de)變化。根據本研究的(de)(de)相關研究結果，活性炭(tan)表(biao)面磺(huang)(huang)胺(an)二甲(jia)啶(ding)的(de)(de)吸(xi)附機制總結如下（圖3）：

　　1.微孔捕獲

　　SEM圖像(xiang)(xiang)顯(xian)示(shi)，活(huo)性炭(tan)的(de)(de)規則孔(kong)(kong)(kong)結(jie)構(gou)受損，孔(kong)(kong)(kong)隙率增(zeng)加。TEM圖像(xiang)(xiang)顯(xian)示(shi)，改(gai)(gai)性活(huo)性炭(tan)表(biao)面含有許多透明點，表(biao)明孔(kong)(kong)(kong)結(jie)構(gou)更發達，修改(gai)(gai)后(hou)可(ke)獲得更多的(de)(de)吸(xi)附點。這(zhe)有利于磺(huang)胺(an)二甲(jia)啶吸(xi)附到黑碳分子層的(de)(de)孔(kong)(kong)(kong)中。此外(wai)，經鐵離子改(gai)(gai)性后(hou)，活(huo)性炭(tan)的(de)(de)表(biao)面積、總(zong)孔(kong)(kong)(kong)容量、微孔(kong)(kong)(kong)體積和中孔(kong)(kong)(kong)體積都有一定程度的(de)(de)增(zeng)加。

　　2.氫鍵(jian)相互作用

　　通(tong)過FTIR通(tong)過促(cu)進改性(xing)活(huo)性(xing)炭表(biao)面(mian)與磺(huang)胺(an)二(er)甲(jia)啶之(zhi)間氫鍵的(de)相互作用(yong)，促(cu)進磺(huang)胺(an)二(er)甲(jia)啶的(de)吸附(fu)。從數據圖中發現(xian)，3400和2850cm-1處寬(kuan)吸收峰(feng)表(biao)明(ming)改性(xing)活(huo)性(xing)炭表(biao)面(mian)存在-OH。這(zhe)些分(fen)子間氫鍵增強(qiang)了磺(huang)胺(an)二(er)甲(jia)啶與活(huo)性(xing)炭的(de)表(biao)面(mian)相互作用(yong)，預計將有助于(yu)活(huo)性(xing)炭與異磺(huang)胺(an)二(er)甲(jia)啶之(zhi)間的(de)親和力吸附(fu)。

　　3.π-π電(dian)子(zi)供(gong)體-受體(EDA)相互作用。

　　磺(huang)胺二(er)甲啶(ding)與改性活性炭合理(li)相(xiang)(xiang)(xiang)(xiang)互(hu)(hu)作(zuo)用的示意圖。1.微孔捕獲(huo)。2.氫鍵相(xiang)(xiang)(xiang)(xiang)互(hu)(hu)作(zuo)用。.π-πEDA相(xiang)(xiang)(xiang)(xiang)互(hu)(hu)作(zuo)用。4.靜電相(xiang)(xiang)(xiang)(xiang)互(hu)(hu)作(zuo)用。5.配位相(xiang)(xiang)(xiang)(xiang)互(hu)(hu)作(zuo)用。

　　鐵離子改性(xing)(xing)后(hou)，活(huo)性(xing)(xing)炭(tan)活(huo)性(xing)(xing)炭(tan)的(de)(de)(de)(de)表面(mian)積、總孔容量(liang)(liang)、微(wei)孔體積和(he)中孔體積。含氧(yang)加(jia)了活(huo)性(xing)(xing)炭(tan)表面(mian)含氧(yang)官(guan)能團的(de)(de)(de)(de)數量(liang)(liang)，可以大大提高(gao)吸(xi)(xi)(xi)附(fu)(fu)(fu)能力(li)。磺(huang)胺(an)二(er)甲(jia)嘧啶(ding)(ding)(ding)在(zai)(zai)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上去除磺(huang)胺(an)廢水中顯(xian)著(zhu)增加(jia)，并在(zai)(zai)25℃下磺(huang)胺(an)二(er)甲(jia)嘧啶(ding)(ding)(ding)在(zai)(zai)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上的(de)(de)(de)(de)*大吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)(liang)為17.261mg/g。然而，吸(xi)(xi)(xi)附(fu)(fu)(fu)平衡時間(jian)(jian)幾乎保持(chi)不變。磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)在(zai)(zai)原始和(he)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上的(de)(de)(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)動力(li)學分為快速(su)和(he)慢速(su)吸(xi)(xi)(xi)附(fu)(fu)(fu)階段，磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)吸(xi)(xi)(xi)附(fu)(fu)(fu)在(zai)(zai)12小時內(nei)快速(su)完成(cheng)。pH該(gai)值對磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)的(de)(de)(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)有顯(xian)著(zhu)影響。當pH磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)的(de)(de)(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)(liang)在(zai)(zai)3-10之間(jian)(jian)增加(jia)，然后(hou)減少。微(wei)孔捕(bu)獲，靜電(dian)相互作用(yong)，氫鍵相互作用(yong)，π-πEDA相互作用(yong)和(he)配(pei)位相互作用(yong)是吸(xi)(xi)(xi)附(fu)(fu)(fu)的(de)(de)(de)(de)可能機制。降低溫度促進吸(xi)(xi)(xi)附(fu)(fu)(fu)反應。pH該(gai)值對磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)的(de)(de)(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)有顯(xian)著(zhu)影響。當pH磺(huang)胺(an)二(er)甲(jia)啶(ding)(ding)(ding)的(de)(de)(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)量(liang)(liang)在(zai)(zai)3-10之間(jian)(jian)增加(jia)，然后(hou)減少。