活性炭改性后處理磺(huang)胺廢(fei)水(shui)

　　磺(huang)胺(an)廢(fei)水經(jing)(jing)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(jing)(jing)氯化鐵改(gai)性(xing)(xing)。并進行批量實(shi)驗以(yi)評估廢(fei)水中的磺(huang)胺(an)二甲(jia)嘧啶吸附到活(huo)性(xing)(xing)炭(tan)和(he)改(gai)性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上(shang)(shang)的平衡，分(fen)別分(fen)析(xi)動力學(xue)(xue)和(he)熱力學(xue)(xue)特(te)征。結果(guo)表明，氯化鐵處理(li)后(hou)，活(huo)性(xing)(xing)炭(tan)改(gai)變了表面(mian)積、孔隙體積和(he)表面(mian)zeta電位(wei)還增加了表面(mian)含氧官能團的數量。經(jing)(jing)試驗發現，磺(huang)胺(an)二甲(jia)啶在改(gai)性(xing)(xing)活(huo)性(xing)(xing)炭(tan)上(shang)(shang)的吸附得(de)到了顯著改(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(chu)顏色、氣味、無機化(hua)合物和(he)大多(duo)數(shu)有機污(wu)染物。但其(qi)在實際應用(yong)中的使用(yong)受其(qi)吸附效率和(he)成本低的限(xian)制。金屬離子改性(xing)(xing)(xing)后(hou)的活性(xing)(xing)(xing)炭(tan)生產(chan)簡單便(bian)宜，能(neng)顯(xian)著(zhu)提(ti)高活性(xing)(xing)(xing)炭(tan)的吸附性(xing)(xing)(xing)能(neng)。然而，活性(xing)(xing)(xing)炭(tan)中磺(huang)(huang)(huang)胺類廢(fei)水的吸附機制尚(shang)不清楚(chu)，對磺(huang)(huang)(huang)胺類的吸附能(neng)力及其(qi)理化(hua)性(xing)(xing)(xing)質知之甚少。本研(yan)究(jiu)采用(yong)鐵離子改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)。用(yong)于探索吸附機制的批量吸附實驗。磺(huang)(huang)(huang)胺二甲啶(ding)對活性(xing)(xing)(xing)炭(tan)和(he)改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)的吸附特性(xing)(xing)(xing)通過吸附動力學、吸附熱力學和(he)吸附等溫線進行(xing)了研(yan)究(jiu)，為去除(chu)廢(fei)水中的磺(huang)(huang)(huang)胺污(wu)染物提(ti)供了科(ke)學依據。

　　活性炭(tan)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)和(he)(he)(he)(he)改(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)的(de)(de)(de)化(hua)學結(jie)構(gou)和(he)(he)(he)(he)物理(li)化(hua)學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異很(hen)大。鐵(tie)離(li)(li)子(zi)改(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)的(de)(de)(de)表(biao)面(mian)積、總孔(kong)(kong)(kong)容量、微(wei)(wei)(wei)(wei)孔(kong)(kong)(kong)體(ti)積和(he)(he)(he)(he)中(zhong)孔(kong)(kong)(kong)體(ti)積都有(you)一(yi)(yi)定程度的(de)(de)(de)增(zeng)(zeng)加，可(ke)以(yi)為(wei)磺胺(an)二(er)甲(jia)啶(ding)提(ti)供更多(duo)的(de)(de)(de)吸附(fu)點(dian)。由于(yu)改(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)的(de)(de)(de)微(wei)(wei)(wei)(wei)孔(kong)(kong)(kong)結(jie)構(gou)可(ke)能會產生(sheng)較大的(de)(de)(de)比表(biao)面(mian)積。在(zai)活(huo)(huo)(huo)(huo)(huo)化(hua)過程中(zhong)，鐵(tie)離(li)(li)子(zi)主(zhu)要沉積在(zai)介孔(kong)(kong)(kong)中(zhong)，擴大孔(kong)(kong)(kong)徑并進(jin)入微(wei)(wei)(wei)(wei)孔(kong)(kong)(kong)。將金屬鹽釋放的(de)(de)(de)氧(yang)化(hua)氣體(ti)引(yin)入微(wei)(wei)(wei)(wei)孔(kong)(kong)(kong)，并與(yu)(yu)微(wei)(wei)(wei)(wei)孔(kong)(kong)(kong)碳(tan)壁反應。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)和(he)(he)(he)(he)改(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)SEM圖(tu)(tu)(tu)1顯(xian)示(shi)圖(tu)(tu)(tu)像(a)和(he)(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)的(de)(de)(de)形(xing)狀表(biao)明(ming)(ming)具有(you)規則(ze)孔(kong)(kong)(kong)結(jie)構(gou)的(de)(de)(de)光滑表(biao)面(mian)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)相(xiang)(xiang)比，改(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)表(biao)面(mian)粗糙(cao)不規則(ze)。孔(kong)(kong)(kong)隙(xi)(xi)結(jie)構(gou)受損，孔(kong)(kong)(kong)隙(xi)(xi)率增(zeng)(zeng)加。這(zhe)可(ke)能是由于(yu)鐵(tie)離(li)(li)子(zi)引(yin)入活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)內孔(kong)(kong)(kong)，導致碳(tan)壁氧(yang)化(hua)和(he)(he)(he)(he)孔(kong)(kong)(kong)徑增(zeng)(zeng)加。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)中(zhong)磺胺(an)二(er)甲(jia)啶(ding)的(de)(de)(de)擴散有(you)利于(yu)粗糙(cao)的(de)(de)(de)表(biao)面(mian)結(jie)構(gou)和(he)(he)(he)(he)多(duo)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)和(he)(he)(he)(he)改(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)TEM圖(tu)(tu)(tu)像如圖(tu)(tu)(tu)1(c)和(he)(he)(he)(he)(d)所(suo)示(shi)。這(zhe)些圖(tu)(tu)(tu)片(pian)表(biao)明(ming)(ming)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)是無定形(xing)的(de)(de)(de)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)相(xiang)(xiang)比，改(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)表(biao)現出許多(duo)孔(kong)(kong)(kong)隙(xi)(xi)和(he)(he)(he)(he)透(tou)明(ming)(ming)點(dian)，進(jin)一(yi)(yi)步表(biao)明(ming)(ming)表(biao)面(mian)積增(zeng)(zeng)加。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)和(he)(he)(he)(he)改(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)EDS圖(tu)(tu)(tu)像如圖(tu)(tu)(tu)1(e)和(he)(he)(he)(he)(f)所(suo)示(shi)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)相(xiang)(xiang)比，改(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)的(de)(de)(de)元(yuan)素O和(he)(he)(he)(he)Fe含(han)量顯(xian)著(zhu)增(zeng)(zeng)加，C活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)上鐵(tie)離(li)(li)子(zi)負荷的(de)(de)(de)含(han)量降低。此外(wai)，進(jin)一(yi)(yi)步證(zheng)明(ming)(ming)表(biao)面(mian)含(han)氧(yang)量增(zeng)(zeng)加，有(you)利于(yu)磺胺(an)二(er)甲(jia)啶(ding)的(de)(de)(de)吸附(fu)。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)和(he)(he)(he)(he)改(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)XRD圖(tu)(tu)(tu)如圖(tu)(tu)(tu)1(g)和(he)(he)(he)(he)(h)所(suo)示(shi)。而且(qie)沒(mei)有(you)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)和(he)(he)(he)(he)改(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)的(de)(de)(de)明(ming)(ming)顯(xian)特征峰值，說(shuo)明(ming)(ming)它們是無形(xing)的(de)(de)(de)。這(zhe)與(yu)(yu)TEM照片(pian)結(jie)果一(yi)(yi)致。

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

　　活性炭吸(xi)附(fu)磺胺的三(san)個階段

　　活(huo)性(xing)(xing)(xing)炭和(he)改性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭和(he)改性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭上的吸(xi)(xi)(xi)附(fu)和(he)擴(kuo)散(san)(san)過程(cheng)(cheng)可分(fen)三個(ge)階(jie)段(duan)(duan)描述，如圖2所示。由于**階(jie)段(duan)(duan)吸(xi)(xi)(xi)附(fu)在活(huo)性(xing)(xing)(xing)炭表(biao)面，吸(xi)(xi)(xi)附(fu)率(lv)*初很(hen)高。然后(hou)，在顆粒(li)(li)內快速擴(kuo)散(san)(san)的過程(cheng)(cheng)中，磺胺二(er)甲(jia)啶(ding)逐(zhu)漸(jian)吸(xi)(xi)(xi)附(fu)在活(huo)性(xing)(xing)(xing)炭上，吸(xi)(xi)(xi)附(fu)率(lv)常數逐(zhu)漸(jian)降低。在第三階(jie)段(duan)(duan)，邊界層和(he)傳質阻(zu)力(li)的影響增加(jia)，導(dao)致顆粒(li)(li)擴(kuo)散(san)(san)減慢(man)。所有三個(ge)階(jie)段(duan)(duan)的擬合方程(cheng)(cheng)都沒有通過坐標(biao)的原點(dian)，這表(biao)明顆粒(li)(li)的擴(kuo)散(san)(san)并(bing)不是控制吸(xi)(xi)(xi)附(fu)率(lv)的**步驟(zou)。因此，吸(xi)(xi)(xi)附(fu)過程(cheng)(cheng)也受膜擴(kuo)散(san)(san)和(he)表(biao)面吸(xi)(xi)(xi)附(fu)的影響。

　　磺胺二甲啶在活性炭上吸附的顆粒(li)中擴散(san)。

　　改性(xing)活性(xing)炭(tan)的(de)表面顯(xian)示出許多孔隙和(he)透(tou)明(ming)度(du)，大量含氧官能團被(bei)改性(xing)，導致磺胺二(er)甲啶吸附機制的(de)變化。根據本(ben)研(yan)究的(de)相關研(yan)究結果，活性(xing)炭(tan)表面磺胺二(er)甲啶的(de)吸附機制總結如下（圖3）：

　　1.微孔捕獲

　　SEM圖(tu)像(xiang)顯(xian)示(shi)，活性(xing)炭的(de)(de)規則孔(kong)結構(gou)受損，孔(kong)隙(xi)率增(zeng)加。TEM圖(tu)像(xiang)顯(xian)示(shi)，改(gai)性(xing)活性(xing)炭表面(mian)含有許多(duo)透明點，表明孔(kong)結構(gou)更發達，修改(gai)后(hou)可獲得更多(duo)的(de)(de)吸附點。這有利于磺胺(an)二甲啶吸附到(dao)黑碳分子層的(de)(de)孔(kong)中。此外，經鐵離子改(gai)性(xing)后(hou)，活性(xing)炭的(de)(de)表面(mian)積、總孔(kong)容(rong)量、微孔(kong)體(ti)積和中孔(kong)體(ti)積都(dou)有一定程度的(de)(de)增(zeng)加。

　　2.氫鍵相互作(zuo)用

　　通過FTIR通過促進改(gai)(gai)性(xing)(xing)活性(xing)(xing)炭(tan)(tan)表(biao)面(mian)與磺胺二(er)甲啶之間(jian)氫鍵的(de)相(xiang)互作用，促進磺胺二(er)甲啶的(de)吸附。從數據圖中發(fa)現，3400和2850cm-1處寬吸收峰表(biao)明改(gai)(gai)性(xing)(xing)活性(xing)(xing)炭(tan)(tan)表(biao)面(mian)存在-OH。這些分子間(jian)氫鍵增(zeng)強了磺胺二(er)甲啶與活性(xing)(xing)炭(tan)(tan)的(de)表(biao)面(mian)相(xiang)互作用，預計(ji)將有助于活性(xing)(xing)炭(tan)(tan)與異磺胺二(er)甲啶之間(jian)的(de)親(qin)和力(li)吸附。

　　3.π-π電(dian)子(zi)供體-受體(EDA)相互作(zuo)用(yong)。

　　磺胺二甲啶與改性活性炭合理相(xiang)互(hu)(hu)作(zuo)用的(de)示意(yi)圖(tu)。1.微孔捕獲(huo)。2.氫鍵相(xiang)互(hu)(hu)作(zuo)用。.π-πEDA相(xiang)互(hu)(hu)作(zuo)用。4.靜電相(xiang)互(hu)(hu)作(zuo)用。5.配位相(xiang)互(hu)(hu)作(zuo)用。

　　鐵離子(zi)改(gai)性(xing)(xing)后(hou)，活(huo)(huo)性(xing)(xing)炭(tan)活(huo)(huo)性(xing)(xing)炭(tan)的(de)(de)表面(mian)積(ji)、總(zong)孔容量、微孔體積(ji)和(he)中孔體積(ji)。含(han)氧加了活(huo)(huo)性(xing)(xing)炭(tan)表面(mian)含(han)氧官能(neng)團的(de)(de)數量，可(ke)以(yi)大(da)大(da)提(ti)高(gao)吸(xi)(xi)(xi)附(fu)能(neng)力(li)。磺(huang)胺(an)二(er)甲(jia)(jia)(jia)嘧(mi)啶(ding)在(zai)改(gai)性(xing)(xing)活(huo)(huo)性(xing)(xing)炭(tan)上去除磺(huang)胺(an)廢水中顯(xian)著增(zeng)(zeng)加，并在(zai)25℃下磺(huang)胺(an)二(er)甲(jia)(jia)(jia)嘧(mi)啶(ding)在(zai)改(gai)性(xing)(xing)活(huo)(huo)性(xing)(xing)炭(tan)上的(de)(de)*大(da)吸(xi)(xi)(xi)附(fu)量為(wei)17.261mg/g。然而，吸(xi)(xi)(xi)附(fu)平衡時間幾乎(hu)保持不變。磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)在(zai)原始(shi)和(he)改(gai)性(xing)(xing)活(huo)(huo)性(xing)(xing)炭(tan)上的(de)(de)吸(xi)(xi)(xi)附(fu)動力(li)學(xue)分為(wei)快速和(he)慢速吸(xi)(xi)(xi)附(fu)階(jie)段，磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)吸(xi)(xi)(xi)附(fu)在(zai)12小時內快速完成。pH該值(zhi)對磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)有顯(xian)著影響。當pH磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)量在(zai)3-10之間增(zeng)(zeng)加，然后(hou)減少。微孔捕獲，靜電相(xiang)互作(zuo)用，氫鍵相(xiang)互作(zuo)用，π-πEDA相(xiang)互作(zuo)用和(he)配位相(xiang)互作(zuo)用是吸(xi)(xi)(xi)附(fu)的(de)(de)可(ke)能(neng)機制。降低溫度促進吸(xi)(xi)(xi)附(fu)反應(ying)。pH該值(zhi)對磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)有顯(xian)著影響。當pH磺(huang)胺(an)二(er)甲(jia)(jia)(jia)啶(ding)的(de)(de)吸(xi)(xi)(xi)附(fu)量在(zai)3-10之間增(zeng)(zeng)加，然后(hou)減少。