活性炭改性后處理磺胺(an)廢水

　　磺(huang)胺廢(fei)水經活性(xing)炭(tan)(tan)改性(xing)后處(chu)理，活性(xing)炭(tan)(tan)經氯化鐵(tie)(tie)改性(xing)。并進行(xing)批量實驗以評(ping)估(gu)廢(fei)水中的磺(huang)胺二(er)甲(jia)嘧啶吸附到活性(xing)炭(tan)(tan)和改性(xing)活性(xing)炭(tan)(tan)上(shang)的平衡，分別(bie)分析動力學和熱力學特征(zheng)。結(jie)果表明，氯化鐵(tie)(tie)處(chu)理后，活性(xing)炭(tan)(tan)改變了表面積、孔(kong)隙體積和表面zeta電位還增加(jia)了表面含(han)氧官能團的數量。經試驗發(fa)現，磺(huang)胺二(er)甲(jia)啶在改性(xing)活性(xing)炭(tan)(tan)上(shang)的吸附得到了顯著改善。

　　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，活性炭能有效去除顏色、氣味、無機化(hua)合物和大多(duo)數(shu)有機污染(ran)(ran)物。但(dan)其(qi)在實(shi)際(ji)應用(yong)中的(de)(de)使用(yong)受其(qi)吸(xi)(xi)(xi)附(fu)(fu)(fu)效率和成(cheng)本(ben)低的(de)(de)限制(zhi)。金屬離子改(gai)性(xing)(xing)(xing)(xing)后的(de)(de)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)生產簡單便(bian)宜，能顯著提高(gao)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)性(xing)(xing)(xing)(xing)能。然(ran)而，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)中磺胺(an)(an)類廢水的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)機制(zhi)尚不清楚，對磺胺(an)(an)類的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)能力及(ji)其(qi)理化(hua)性(xing)(xing)(xing)(xing)質(zhi)知之甚少。本(ben)研(yan)(yan)究(jiu)采(cai)用(yong)鐵離子改(gai)性(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)。用(yong)于探索吸(xi)(xi)(xi)附(fu)(fu)(fu)機制(zhi)的(de)(de)批量吸(xi)(xi)(xi)附(fu)(fu)(fu)實(shi)驗。磺胺(an)(an)二甲啶對活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)和改(gai)性(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)(de)吸(xi)(xi)(xi)附(fu)(fu)(fu)特性(xing)(xing)(xing)(xing)通(tong)過吸(xi)(xi)(xi)附(fu)(fu)(fu)動力學、吸(xi)(xi)(xi)附(fu)(fu)(fu)熱力學和吸(xi)(xi)(xi)附(fu)(fu)(fu)等溫線(xian)進行(xing)了研(yan)(yan)究(jiu)，為去除廢水中的(de)(de)磺胺(an)(an)污染(ran)(ran)物提供了科學依據。

　　活(huo)性炭(tan)改性后(hou)的特(te)性

　　活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)化學結(jie)構(gou)和(he)(he)物(wu)理化學性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)質差異很大。鐵(tie)(tie)離子改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)后，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)表(biao)面(mian)(mian)(mian)(mian)積、總(zong)孔容量(liang)、微孔體(ti)積和(he)(he)中(zhong)孔體(ti)積都有一(yi)定(ding)程度(du)的(de)(de)(de)(de)增加(jia)，可以為磺(huang)胺(an)二(er)甲啶(ding)(ding)提供更多(duo)的(de)(de)(de)(de)吸(xi)附點。由于(yu)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)微孔結(jie)構(gou)可能(neng)會產生較(jiao)大的(de)(de)(de)(de)比表(biao)面(mian)(mian)(mian)(mian)積。在活(huo)(huo)化過程中(zhong)，鐵(tie)(tie)離子主要沉積在介(jie)孔中(zhong)，擴大孔徑(jing)(jing)并進(jin)入(ru)(ru)微孔。將金屬(shu)鹽釋放(fang)的(de)(de)(de)(de)氧(yang)化氣體(ti)引入(ru)(ru)微孔，并與微孔碳壁反(fan)應。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)SEM圖(tu)(tu)(tu)1顯示圖(tu)(tu)(tu)像(xiang)(a)和(he)(he)(b)中(zhong)。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)形狀表(biao)明(ming)(ming)(ming)具有規(gui)則(ze)孔結(jie)構(gou)的(de)(de)(de)(de)光滑表(biao)面(mian)(mian)(mian)(mian)。與活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比，改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)面(mian)(mian)(mian)(mian)粗(cu)糙(cao)不規(gui)則(ze)。孔隙(xi)結(jie)構(gou)受損，孔隙(xi)率增加(jia)。這(zhe)可能(neng)是(shi)由于(yu)鐵(tie)(tie)離子引入(ru)(ru)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)內孔，導致碳壁氧(yang)化和(he)(he)孔徑(jing)(jing)增加(jia)。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)中(zhong)磺(huang)胺(an)二(er)甲啶(ding)(ding)的(de)(de)(de)(de)擴散有利于(yu)粗(cu)糙(cao)的(de)(de)(de)(de)表(biao)面(mian)(mian)(mian)(mian)結(jie)構(gou)和(he)(he)多(duo)孔特性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)TEM圖(tu)(tu)(tu)像(xiang)如圖(tu)(tu)(tu)1(c)和(he)(he)(d)所(suo)示。這(zhe)些圖(tu)(tu)(tu)片表(biao)明(ming)(ming)(ming)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)是(shi)無(wu)定(ding)形的(de)(de)(de)(de)。與活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比，改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)表(biao)現出許多(duo)孔隙(xi)和(he)(he)透明(ming)(ming)(ming)點，進(jin)一(yi)步(bu)(bu)表(biao)明(ming)(ming)(ming)表(biao)面(mian)(mian)(mian)(mian)積增加(jia)。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)EDS圖(tu)(tu)(tu)像(xiang)如圖(tu)(tu)(tu)1(e)和(he)(he)(f)所(suo)示。與活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)相比，改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)元素O和(he)(he)Fe含量(liang)顯著增加(jia)，C活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)上鐵(tie)(tie)離子負荷的(de)(de)(de)(de)含量(liang)降低。此外，進(jin)一(yi)步(bu)(bu)證(zheng)明(ming)(ming)(ming)表(biao)面(mian)(mian)(mian)(mian)含氧(yang)量(liang)增加(jia)，有利于(yu)磺(huang)胺(an)二(er)甲啶(ding)(ding)的(de)(de)(de)(de)吸(xi)附。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)XRD圖(tu)(tu)(tu)如圖(tu)(tu)(tu)1(g)和(he)(he)(h)所(suo)示。而且(qie)沒有活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)和(he)(he)改(gai)(gai)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)(de)明(ming)(ming)(ming)顯特征(zheng)峰值(zhi)，說明(ming)(ming)(ming)它們是(shi)無(wu)形的(de)(de)(de)(de)。這(zhe)與TEM照片結(jie)果(guo)一(yi)致。

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

　　活性炭吸附磺胺的(de)三個階(jie)段

　　活(huo)(huo)(huo)性(xing)(xing)炭(tan)和改性(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)炭(tan)和改性(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)炭(tan)上的(de)吸(xi)(xi)(xi)附(fu)和擴散(san)過程可分三(san)個階段(duan)(duan)(duan)描述，如(ru)圖2所示。由于(yu)**階段(duan)(duan)(duan)吸(xi)(xi)(xi)附(fu)在活(huo)(huo)(huo)性(xing)(xing)炭(tan)表(biao)面(mian)，吸(xi)(xi)(xi)附(fu)率*初很高。然后，在顆粒內快速擴散(san)的(de)過程中，磺胺(an)二甲啶逐漸吸(xi)(xi)(xi)附(fu)在活(huo)(huo)(huo)性(xing)(xing)炭(tan)上，吸(xi)(xi)(xi)附(fu)率常數逐漸降低。在第三(san)階段(duan)(duan)(duan)，邊界層和傳質阻力的(de)影響增加，導致顆粒擴散(san)減慢。所有三(san)個階段(duan)(duan)(duan)的(de)擬合方程都沒有通(tong)過坐標的(de)原(yuan)點，這表(biao)明顆粒的(de)擴散(san)并不(bu)是控制吸(xi)(xi)(xi)附(fu)率的(de)**步驟(zou)。因此，吸(xi)(xi)(xi)附(fu)過程也受(shou)膜擴散(san)和表(biao)面(mian)吸(xi)(xi)(xi)附(fu)的(de)影響。

　　磺胺二甲啶(ding)在(zai)活性(xing)炭上吸附的(de)顆粒中擴散。

　　改(gai)性(xing)活性(xing)炭(tan)的表面顯(xian)示出許多孔隙(xi)和透明度，大(da)量含(han)氧官能團被改(gai)性(xing)，導致磺(huang)(huang)胺二甲啶(ding)吸(xi)附機制(zhi)的變化。根據本研究的相關研究結果，活性(xing)炭(tan)表面磺(huang)(huang)胺二甲啶(ding)的吸(xi)附機制(zhi)總結如(ru)下（圖3）：

　　1.微孔捕獲

　　SEM圖像顯(xian)示(shi)，活性炭的(de)規則(ze)孔(kong)結構受損(sun)，孔(kong)隙率增(zeng)(zeng)加。TEM圖像顯(xian)示(shi)，改性活性炭表面含有許多(duo)透明(ming)點(dian)，表明(ming)孔(kong)結構更發(fa)達(da)，修改后(hou)可獲得更多(duo)的(de)吸附(fu)點(dian)。這(zhe)有利于磺胺(an)二甲啶吸附(fu)到黑碳分子(zi)層(ceng)的(de)孔(kong)中(zhong)(zhong)。此外，經鐵離子(zi)改性后(hou)，活性炭的(de)表面積(ji)、總孔(kong)容量、微孔(kong)體(ti)積(ji)和中(zhong)(zhong)孔(kong)體(ti)積(ji)都有一定(ding)程(cheng)度的(de)增(zeng)(zeng)加。

　　2.氫鍵相互(hu)作用

　　通過FTIR通過促進改(gai)性活(huo)性炭表面(mian)(mian)與磺(huang)胺(an)二(er)甲(jia)啶(ding)之間(jian)氫(qing)鍵(jian)的(de)相互作(zuo)(zuo)用，促進磺(huang)胺(an)二(er)甲(jia)啶(ding)的(de)吸附。從(cong)數據圖中(zhong)發現，3400和2850cm-1處寬吸收峰表明改(gai)性活(huo)性炭表面(mian)(mian)存(cun)在(zai)-OH。這些分子間(jian)氫(qing)鍵(jian)增強了磺(huang)胺(an)二(er)甲(jia)啶(ding)與活(huo)性炭的(de)表面(mian)(mian)相互作(zuo)(zuo)用，預(yu)計將有(you)助于活(huo)性炭與異磺(huang)胺(an)二(er)甲(jia)啶(ding)之間(jian)的(de)親和力吸附。

　　3.π-π電子供體-受體(EDA)相互作用。

　　磺胺二(er)甲啶與(yu)改性活性炭合理(li)相互(hu)作(zuo)用(yong)(yong)的示意圖。1.微(wei)孔捕獲。2.氫(qing)鍵相互(hu)作(zuo)用(yong)(yong)。.π-πEDA相互(hu)作(zuo)用(yong)(yong)。4.靜(jing)電相互(hu)作(zuo)用(yong)(yong)。5.配位(wei)相互(hu)作(zuo)用(yong)(yong)。

　　鐵離子(zi)改性(xing)(xing)(xing)后(hou)，活(huo)(huo)(huo)性(xing)(xing)(xing)炭活(huo)(huo)(huo)性(xing)(xing)(xing)炭的(de)(de)表面積、總孔(kong)(kong)容量、微(wei)孔(kong)(kong)體積和(he)中孔(kong)(kong)體積。含(han)氧加(jia)了活(huo)(huo)(huo)性(xing)(xing)(xing)炭表面含(han)氧官能(neng)(neng)團(tuan)的(de)(de)數量，可以大(da)大(da)提高吸附(fu)(fu)(fu)(fu)(fu)能(neng)(neng)力(li)。磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)嘧啶(ding)在(zai)改性(xing)(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)(xing)炭上(shang)去除磺(huang)(huang)(huang)(huang)胺(an)(an)廢(fei)水(shui)中顯著增加(jia)，并在(zai)25℃下磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)嘧啶(ding)在(zai)改性(xing)(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)(xing)炭上(shang)的(de)(de)*大(da)吸附(fu)(fu)(fu)(fu)(fu)量為17.261mg/g。然(ran)而(er)，吸附(fu)(fu)(fu)(fu)(fu)平衡時間(jian)幾乎保持不(bu)變(bian)。磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)在(zai)原始(shi)和(he)改性(xing)(xing)(xing)活(huo)(huo)(huo)性(xing)(xing)(xing)炭上(shang)的(de)(de)吸附(fu)(fu)(fu)(fu)(fu)動力(li)學(xue)分為快(kuai)速和(he)慢速吸附(fu)(fu)(fu)(fu)(fu)階段，磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)吸附(fu)(fu)(fu)(fu)(fu)在(zai)12小時內快(kuai)速完成(cheng)。pH該值對磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)的(de)(de)吸附(fu)(fu)(fu)(fu)(fu)有顯著影(ying)響(xiang)。當pH磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)的(de)(de)吸附(fu)(fu)(fu)(fu)(fu)量在(zai)3-10之間(jian)增加(jia)，然(ran)后(hou)減少。微(wei)孔(kong)(kong)捕獲，靜電相(xiang)互(hu)作(zuo)(zuo)用(yong)(yong)，氫鍵(jian)相(xiang)互(hu)作(zuo)(zuo)用(yong)(yong)，π-πEDA相(xiang)互(hu)作(zuo)(zuo)用(yong)(yong)和(he)配位相(xiang)互(hu)作(zuo)(zuo)用(yong)(yong)是吸附(fu)(fu)(fu)(fu)(fu)的(de)(de)可能(neng)(neng)機制。降(jiang)低溫度促進吸附(fu)(fu)(fu)(fu)(fu)反應。pH該值對磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)的(de)(de)吸附(fu)(fu)(fu)(fu)(fu)有顯著影(ying)響(xiang)。當pH磺(huang)(huang)(huang)(huang)胺(an)(an)二(er)(er)甲(jia)啶(ding)的(de)(de)吸附(fu)(fu)(fu)(fu)(fu)量在(zai)3-10之間(jian)增加(jia)，然(ran)后(hou)減少。