活性炭改性后(hou)處(chu)理磺(huang)胺廢水(shui)

　　磺胺廢水經活(huo)性(xing)(xing)(xing)炭(tan)(tan)改(gai)性(xing)(xing)(xing)后處理(li)，活(huo)性(xing)(xing)(xing)炭(tan)(tan)經氯(lv)化(hua)鐵改(gai)性(xing)(xing)(xing)。并進(jin)行批量(liang)實(shi)驗以評估廢水中(zhong)的(de)磺胺二甲嘧啶吸附(fu)到活(huo)性(xing)(xing)(xing)炭(tan)(tan)和改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭(tan)(tan)上(shang)的(de)平衡，分別分析(xi)動力(li)學(xue)(xue)和熱力(li)學(xue)(xue)特(te)征。結果(guo)表(biao)(biao)明，氯(lv)化(hua)鐵處理(li)后，活(huo)性(xing)(xing)(xing)炭(tan)(tan)改(gai)變了(le)表(biao)(biao)面積、孔隙(xi)體積和表(biao)(biao)面zeta電位還(huan)增(zeng)加(jia)了(le)表(biao)(biao)面含氧官能團的(de)數量(liang)。經試驗發現，磺胺二甲啶在改(gai)性(xing)(xing)(xing)活(huo)性(xing)(xing)(xing)炭(tan)(tan)上(shang)的(de)吸附(fu)得到了(le)顯(xian)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(you)效去(qu)除顏色、氣味、無機化合物(wu)(wu)和大多數有(you)機污染(ran)物(wu)(wu)。但其在實際應(ying)用(yong)中(zhong)(zhong)的(de)(de)使用(yong)受(shou)其吸(xi)(xi)附(fu)效率和成本低的(de)(de)限制(zhi)(zhi)。金屬(shu)離子改(gai)性后(hou)的(de)(de)活(huo)(huo)性炭(tan)生產簡單便(bian)宜，能顯著(zhu)提高活(huo)(huo)性炭(tan)的(de)(de)吸(xi)(xi)附(fu)性能。然(ran)而，活(huo)(huo)性炭(tan)中(zhong)(zhong)磺(huang)胺類廢水的(de)(de)吸(xi)(xi)附(fu)機制(zhi)(zhi)尚不(bu)清楚，對磺(huang)胺類的(de)(de)吸(xi)(xi)附(fu)能力(li)及其理化性質知(zhi)之甚少。本研(yan)究采用(yong)鐵(tie)離子改(gai)性活(huo)(huo)性炭(tan)。用(yong)于探(tan)索吸(xi)(xi)附(fu)機制(zhi)(zhi)的(de)(de)批量吸(xi)(xi)附(fu)實驗。磺(huang)胺二甲啶(ding)對活(huo)(huo)性炭(tan)和改(gai)性活(huo)(huo)性炭(tan)的(de)(de)吸(xi)(xi)附(fu)特性通過吸(xi)(xi)附(fu)動(dong)力(li)學、吸(xi)(xi)附(fu)熱力(li)學和吸(xi)(xi)附(fu)等溫(wen)線進行了(le)(le)研(yan)究，為去(qu)除廢水中(zhong)(zhong)的(de)(de)磺(huang)胺污染(ran)物(wu)(wu)提供了(le)(le)科學依據。

　　活性(xing)炭改性(xing)后的(de)特性(xing)

　　活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)化學結(jie)(jie)構(gou)和物(wu)理(li)化學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異(yi)很(hen)大。鐵離(li)子(zi)(zi)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)后(hou)，活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)表(biao)(biao)(biao)(biao)(biao)面(mian)積、總孔(kong)(kong)容(rong)量、微孔(kong)(kong)體(ti)(ti)積和中(zhong)(zhong)孔(kong)(kong)體(ti)(ti)積都有一(yi)(yi)定(ding)程度的(de)(de)(de)增(zeng)加(jia)，可以為磺(huang)(huang)胺(an)二(er)甲啶提供(gong)更多(duo)的(de)(de)(de)吸附點(dian)。由于(yu)改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)，活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)微孔(kong)(kong)結(jie)(jie)構(gou)可能(neng)會(hui)產生較大的(de)(de)(de)比表(biao)(biao)(biao)(biao)(biao)面(mian)積。在活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)化過程中(zhong)(zhong)，鐵離(li)子(zi)(zi)主要沉(chen)積在介(jie)孔(kong)(kong)中(zhong)(zhong)，擴(kuo)大孔(kong)(kong)徑并進入(ru)微孔(kong)(kong)。將金屬鹽(yan)釋放的(de)(de)(de)氧(yang)化氣體(ti)(ti)引入(ru)微孔(kong)(kong)，并與(yu)(yu)微孔(kong)(kong)碳壁反應。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)SEM圖(tu)1顯示(shi)圖(tu)像(xiang)(a)和(b)中(zhong)(zhong)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)形狀表(biao)(biao)(biao)(biao)(biao)明(ming)(ming)具有規則孔(kong)(kong)結(jie)(jie)構(gou)的(de)(de)(de)光(guang)滑表(biao)(biao)(biao)(biao)(biao)面(mian)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)(biao)(biao)(biao)(biao)面(mian)粗(cu)糙不(bu)規則。孔(kong)(kong)隙(xi)結(jie)(jie)構(gou)受損，孔(kong)(kong)隙(xi)率增(zeng)加(jia)。這可能(neng)是由于(yu)鐵離(li)子(zi)(zi)引入(ru)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)內孔(kong)(kong)，導(dao)致碳壁氧(yang)化和孔(kong)(kong)徑增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)中(zhong)(zhong)磺(huang)(huang)胺(an)二(er)甲啶的(de)(de)(de)擴(kuo)散有利于(yu)粗(cu)糙的(de)(de)(de)表(biao)(biao)(biao)(biao)(biao)面(mian)結(jie)(jie)構(gou)和多(duo)孔(kong)(kong)特性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)TEM圖(tu)像(xiang)如(ru)圖(tu)1(c)和(d)所(suo)示(shi)。這些圖(tu)片表(biao)(biao)(biao)(biao)(biao)明(ming)(ming)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)是無定(ding)形的(de)(de)(de)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)(biao)(biao)(biao)(biao)現出許多(duo)孔(kong)(kong)隙(xi)和透明(ming)(ming)點(dian)，進一(yi)(yi)步表(biao)(biao)(biao)(biao)(biao)明(ming)(ming)表(biao)(biao)(biao)(biao)(biao)面(mian)積增(zeng)加(jia)。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)EDS圖(tu)像(xiang)如(ru)圖(tu)1(e)和(f)所(suo)示(shi)。與(yu)(yu)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相(xiang)比，改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)元素(su)O和Fe含量顯著增(zeng)加(jia)，C活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)上鐵離(li)子(zi)(zi)負荷的(de)(de)(de)含量降低。此外(wai)，進一(yi)(yi)步證明(ming)(ming)表(biao)(biao)(biao)(biao)(biao)面(mian)含氧(yang)量增(zeng)加(jia)，有利于(yu)磺(huang)(huang)胺(an)二(er)甲啶的(de)(de)(de)吸附。活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)XRD圖(tu)如(ru)圖(tu)1(g)和(h)所(suo)示(shi)。而且沒有活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和改性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)(huo)(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)明(ming)(ming)顯特征峰值(zhi)，說(shuo)明(ming)(ming)它們是無形的(de)(de)(de)。這與(yu)(yu)TEM照片結(jie)(jie)果(guo)一(yi)(yi)致。

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

　　活性炭吸(xi)附磺(huang)胺的(de)三個階段

　　活性(xing)(xing)(xing)炭(tan)和(he)(he)(he)改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)和(he)(he)(he)改性(xing)(xing)(xing)活性(xing)(xing)(xing)炭(tan)上的吸附(fu)(fu)和(he)(he)(he)擴(kuo)(kuo)散(san)過(guo)程(cheng)(cheng)可(ke)分三個(ge)階段(duan)描述，如圖2所示。由(you)于**階段(duan)吸附(fu)(fu)在活性(xing)(xing)(xing)炭(tan)表面(mian)，吸附(fu)(fu)率*初很高。然后，在顆(ke)粒內快速(su)擴(kuo)(kuo)散(san)的過(guo)程(cheng)(cheng)中，磺胺二(er)甲(jia)啶逐漸吸附(fu)(fu)在活性(xing)(xing)(xing)炭(tan)上，吸附(fu)(fu)率常數(shu)逐漸降低。在第三階段(duan)，邊界層和(he)(he)(he)傳質(zhi)阻(zu)力(li)的影響增加(jia)，導致(zhi)顆(ke)粒擴(kuo)(kuo)散(san)減(jian)慢。所有三個(ge)階段(duan)的擬合(he)方程(cheng)(cheng)都沒有通過(guo)坐標(biao)的原點(dian)，這表明顆(ke)粒的擴(kuo)(kuo)散(san)并不是控制吸附(fu)(fu)率的**步(bu)驟。因此，吸附(fu)(fu)過(guo)程(cheng)(cheng)也(ye)受膜擴(kuo)(kuo)散(san)和(he)(he)(he)表面(mian)吸附(fu)(fu)的影響。

　　磺胺二甲啶在活性炭上(shang)吸附的顆粒(li)中擴散(san)。

　　改(gai)性活性炭的表面顯(xian)示出許(xu)多(duo)孔(kong)隙和透明度，大(da)量含氧官能(neng)團被(bei)改(gai)性，導致磺(huang)胺二(er)甲啶吸(xi)附機制的變化(hua)。根據本研(yan)究(jiu)的相關研(yan)究(jiu)結(jie)果，活性炭表面磺(huang)胺二(er)甲啶的吸(xi)附機制總結(jie)如下（圖3）：

　　1.微孔捕獲

　　SEM圖(tu)像顯(xian)示，活(huo)性炭(tan)的(de)(de)規則孔(kong)(kong)結構受損(sun)，孔(kong)(kong)隙率增加。TEM圖(tu)像顯(xian)示，改性活(huo)性炭(tan)表(biao)面含有許多透(tou)明點，表(biao)明孔(kong)(kong)結構更發達，修改后可獲得更多的(de)(de)吸附(fu)點。這(zhe)有利于磺胺(an)二甲(jia)啶吸附(fu)到黑碳分子層的(de)(de)孔(kong)(kong)中(zhong)。此外，經鐵(tie)離(li)子改性后，活(huo)性炭(tan)的(de)(de)表(biao)面積(ji)、總孔(kong)(kong)容量、微孔(kong)(kong)體(ti)積(ji)和中(zhong)孔(kong)(kong)體(ti)積(ji)都(dou)有一定程(cheng)度的(de)(de)增加。

　　2.氫鍵相互作用

　　通過FTIR通過促進改(gai)性活(huo)性炭表面(mian)與磺胺二甲啶(ding)之間(jian)氫鍵的相互作用(yong)，促進磺胺二甲啶(ding)的吸(xi)附。從數據(ju)圖中(zhong)發(fa)現，3400和2850cm-1處寬吸(xi)收(shou)峰表明(ming)改(gai)性活(huo)性炭表面(mian)存在-OH。這些(xie)分(fen)子間(jian)氫鍵增強(qiang)了磺胺二甲啶(ding)與活(huo)性炭的表面(mian)相互作用(yong)，預計(ji)將有助于活(huo)性炭與異磺胺二甲啶(ding)之間(jian)的親和力吸(xi)附。

　　3.π-π電子供體-受體(EDA)相互作用。

　　磺胺二(er)甲啶與改性活性炭合(he)理相互(hu)作(zuo)(zuo)用(yong)的示(shi)意圖。1.微孔捕(bu)獲。2.氫鍵相互(hu)作(zuo)(zuo)用(yong)。.π-πEDA相互(hu)作(zuo)(zuo)用(yong)。4.靜電相互(hu)作(zuo)(zuo)用(yong)。5.配位相互(hu)作(zuo)(zuo)用(yong)。

　　鐵離子改性(xing)(xing)后，活(huo)性(xing)(xing)炭(tan)(tan)活(huo)性(xing)(xing)炭(tan)(tan)的(de)(de)(de)表面積、總孔容(rong)量(liang)、微孔體(ti)積和(he)中孔體(ti)積。含(han)氧(yang)加(jia)了活(huo)性(xing)(xing)炭(tan)(tan)表面含(han)氧(yang)官能(neng)團(tuan)的(de)(de)(de)數(shu)量(liang)，可(ke)以大大提高吸(xi)(xi)附能(neng)力(li)。磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)嘧啶(ding)(ding)在(zai)(zai)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)(tan)上(shang)去除磺(huang)胺(an)(an)(an)廢水中顯(xian)著增(zeng)加(jia)，并(bing)在(zai)(zai)25℃下磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)嘧啶(ding)(ding)在(zai)(zai)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)(tan)上(shang)的(de)(de)(de)*大吸(xi)(xi)附量(liang)為(wei)17.261mg/g。然(ran)(ran)而，吸(xi)(xi)附平衡時間幾乎(hu)保持不(bu)變。磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)在(zai)(zai)原始和(he)改性(xing)(xing)活(huo)性(xing)(xing)炭(tan)(tan)上(shang)的(de)(de)(de)吸(xi)(xi)附動力(li)學分為(wei)快速和(he)慢速吸(xi)(xi)附階段，磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)吸(xi)(xi)附在(zai)(zai)12小(xiao)時內(nei)快速完成。pH該值對磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)的(de)(de)(de)吸(xi)(xi)附有顯(xian)著影響(xiang)。當(dang)pH磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)的(de)(de)(de)吸(xi)(xi)附量(liang)在(zai)(zai)3-10之間增(zeng)加(jia)，然(ran)(ran)后減(jian)少。微孔捕(bu)獲，靜電(dian)相(xiang)(xiang)互(hu)(hu)作(zuo)用(yong)，氫(qing)鍵(jian)相(xiang)(xiang)互(hu)(hu)作(zuo)用(yong)，π-πEDA相(xiang)(xiang)互(hu)(hu)作(zuo)用(yong)和(he)配(pei)位相(xiang)(xiang)互(hu)(hu)作(zuo)用(yong)是吸(xi)(xi)附的(de)(de)(de)可(ke)能(neng)機制。降(jiang)低溫度促進吸(xi)(xi)附反應(ying)。pH該值對磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)的(de)(de)(de)吸(xi)(xi)附有顯(xian)著影響(xiang)。當(dang)pH磺(huang)胺(an)(an)(an)二(er)甲(jia)(jia)啶(ding)(ding)的(de)(de)(de)吸(xi)(xi)附量(liang)在(zai)(zai)3-10之間增(zeng)加(jia)，然(ran)(ran)后減(jian)少。