【摘要】：水體重金屬污染問(wèn)題不僅威脅著人類(lèi)的健康,而且對(duì)生態(tài)環(huán)境造成了嚴(yán)重的破壞,重金屬?gòu)U水的治理迫在眉睫。吸附法處理含重金屬的廢水具有操作簡(jiǎn)單、價(jià)格低廉、吸附性能好、可回收利用等優(yōu)點(diǎn),已成為一種實(shí)用可靠的水處理方法。吸附劑結(jié)構(gòu)中需要存在能夠吸附重金屬離子的功能基團(tuán),其中羧基和氨基的吸附性能比較優(yōu)秀。因此,研發(fā)出含羧基或多胺基團(tuán)的高效吸附劑具有現(xiàn)實(shí)意義。丙烯酸甲酯(methyl acrylate, MA)是一種雙官能團(tuán)單體,常被用作于有機(jī)合成中間體,也可用來(lái)合成高分子聚合物。本課題以微晶纖維素為載體,MA為接枝聚合單體,通過(guò)硝酸鈰銨(ceric ammonium nitrate, CAN)引發(fā)成功合成纖維素接枝聚丙烯酸甲酯(Cell-g-PMA)。隨后使用氫氧化鈉水解制備了吸附劑纖維素接枝聚丙烯酸鈉(Cell-g-P(AA-Na)),并簡(jiǎn)易的表征了其在水溶液中對(duì)Pb(Ⅱ)和Cu(Ⅱ)重金屬離子的吸附行為。四乙烯五胺(tetraethylenepentamine, TEPA)是一種具有高效重金屬吸附功能的水溶性多胺,本研究通過(guò)Cell-g-PMA與TEPA的胺解反應(yīng)成功制備了多胺類(lèi)改性吸附劑四乙烯五胺改性纖維素接枝聚丙烯酸甲酯(Cell-g-PMA-TEPA),通過(guò)元素分析的表征手段確定了最優(yōu)合成時(shí)間。隨后,通過(guò)FTIR光譜、固態(tài)核磁碳譜、熱失重TG/DTG分析和掃描電鏡(SEM)對(duì)Cell-g-PMA-TEPA的結(jié)構(gòu)和形貌進(jìn)行了表征。為探究Cell-g-PMA-TEPA對(duì)水溶液中重金屬離子的吸附性能,實(shí)驗(yàn)表征了其在水溶液中對(duì)Pb(Ⅱ)和Cu(Ⅱ)重金屬離子的吸附行為,結(jié)果如下：靜態(tài)吸附性能研究中,吸附劑Cell-g-PMA-TEPA對(duì)Pb(Ⅱ)和Cu(Ⅱ)的吸附過(guò)程分別在pH 5.0和pH 4.5時(shí)達(dá)到較好的效果,并均可在200min內(nèi)達(dá)到吸附平衡,所得數(shù)據(jù)表明吸附過(guò)程符合準(zhǔn)二級(jí)動(dòng)力學(xué)吸附模型,即通過(guò)吸附劑與吸附質(zhì)共享或交換電子所形成共價(jià)鍵的化學(xué)吸附。在對(duì)等溫吸附模型的研究中發(fā)現(xiàn)：Langmuir等溫吸附模型能更好的模擬實(shí)驗(yàn)過(guò)程,吸附劑對(duì)吸附質(zhì)的吸附機(jī)理更趨于吸附劑均一表面的單層吸附,并且可推測(cè)出Cell-g-PMA-TEPA對(duì)Pb(Ⅱ)和Cu(Ⅱ)的最大吸附容量分別為444.4mg/g和168.35mg/g。動(dòng)態(tài)吸附性能研究中,吸附劑Cell-g-PMA-TEPA在特定參數(shù)下對(duì)Pb(Ⅱ)和Cu(Ⅱ)的平衡吸附容量分別為440.4mg/g和170.6mg/g,由O.1M稀鹽酸溶液淋洗后可再生吸附。經(jīng)過(guò)五次吸附-洗脫循環(huán)后,平衡吸附容量都沒(méi)有明顯的下降,吸附容量損失均低于10%,吸附劑依然對(duì)Pb(Ⅱ)和Cu(Ⅱ)具有優(yōu)秀的吸附性能。
[Abstract]:Heavy metal pollution not only threatens the health of human beings, but also causes serious damage to the ecological environment. The treatment of heavy metal wastewater is urgent. The treatment of wastewater containing heavy metals by adsorption method has many advantages, such as simple operation, low price, good adsorption performance and recyclability. It has become a practical and reliable water treatment method. In the structure of adsorbent, functional groups are needed to adsorb heavy metal ions, among which the adsorption properties of carboxyl group and amino group are excellent. Therefore, it is of practical significance to develop high-efficiency adsorbents containing carboxyl or polyamine groups. Methyl acrylate (methyl acrylate, MA) is a bifunctional monomer, which is often used as an intermediate in organic synthesis as well as in the synthesis of polymer. In this paper, cellulose grafted methyl acrylate (Cell-g-PMA) was successfully synthesized by cerium ammonium nitrate (ceric ammonium nitrate, CAN) with microcrystalline cellulose as carrier and MA as graft monomer. Then the adsorbent cellulose grafted sodium polyacrylate (Cell-g-P (AA-Na),) was prepared by hydrolysis of sodium hydroxide and the adsorption behavior of Pb (鈪，

本文編號(hào)：2319960