本文選題：茶葉　切入點(diǎn)：納米鐵　出處：《南華大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：納米鐵的制備技術(shù)迅速發(fā)展,方法多種多樣。生物法制備納米鐵因其具備原材料來(lái)源廣,反應(yīng)條件溫和,產(chǎn)物不易團(tuán)聚,以及有毒副產(chǎn)物少等特點(diǎn),成為了學(xué)者們爭(zhēng)相研究的方向。目前關(guān)于生物合成納米鐵的研究還剛起步,因此,合理選擇生物質(zhì)、深入分析其起作用的成分、探討其反應(yīng)機(jī)理、優(yōu)化納米顆粒形態(tài)和尺寸提高產(chǎn)率是納米鐵解決重金屬污染應(yīng)用的發(fā)展方向。本文利用黑茶還原制備出綠色納米鐵(BT-Fe NPs),通過(guò)UV-Vis、SEM、EDX、FTIR、XRD等方法對(duì)BT-Fe NPs進(jìn)行表征。再將此顆粒負(fù)載在凹凸棒(ATP)上進(jìn)行改性,合成新型納米顆�！G色納米鐵/凹凸棒(BT-Fe NPs/ATP)。并檢測(cè)其去除廢水中鉻(Ⅵ)、鉛(Ⅱ)的效率,考察了不同因素對(duì)去除效率的影響,通過(guò)表征分析探究了BT-Fe NPs去除重金屬的機(jī)理。實(shí)驗(yàn)結(jié)果如下:(1)合成的BT-Fe NPs為無(wú)定形的球形顆粒,粒徑100~200nm左右,納米顆粒中的鐵主要以磁赤鐵礦(γ-Fe2O3),磁鐵礦(Fe3O4)和鐵氫氧化物形式存在,顆粒表面包裹C-N,C-O,-OH等有機(jī)基團(tuán)。(2)在25℃,p H=4.0,Cr(Ⅵ)初始濃度20mg/L,反應(yīng)時(shí)間90min條件下,BT-Fe NPs對(duì)Cr(Ⅵ)去除率達(dá)到96.3%。由于包裹了黑茶提取液中的有機(jī)成分,BT-Fe NPs的抗氧化性優(yōu)于化學(xué)法制備的Na BH4-Fe NPs。在室溫下,Pb(Ⅱ)的初始濃度為10mg/L,在p H值為7,BT-Fe NPs/ATP投加量為0.1g,反應(yīng)時(shí)間為90min時(shí),Pb(Ⅱ)的去除率可達(dá)99.8%。(3)改性后,BT-Fe NPs/ATP保持了ATP的層鏈狀結(jié)構(gòu)特征,具有較大的比表面積,橢球形的綠色納米鐵顆粒分散負(fù)載在平行的ATP晶束上,粒徑約為200~500nm,團(tuán)聚現(xiàn)象明顯減少。(4)去除鉻、鉛過(guò)程中起主要作用的基團(tuán)是C-N基團(tuán)和Fe-O鍵,茶葉中的有機(jī)基團(tuán)將重金屬離子吸附在納米顆粒表面,Fe-O鍵進(jìn)而對(duì)其還原,說(shuō)明了綠色納米鐵去除鉻、鉛的過(guò)程是一個(gè)吸附和還原共同作用的復(fù)雜物理化學(xué)過(guò)程。
[Abstract]:The rapid development of the nano iron preparation technology, a variety of methods. The biological preparation of nano iron because it has a wide source of raw materials, mild reaction conditions, the product is not easy to agglomerate and less toxic by-products, become the scholars to research. Current research on the biological synthesis of nano iron has just started therefore, a reasonable choice of biomass, in-depth analysis of its functional components, explore the reaction mechanism, optimize the size and morphology of nanoparticles to improve the yield of nano iron is to solve the development direction of the application of heavy metal pollution. The reduction of black tea prepared green nano iron (BT-Fe NPs) by UV-Vis, SEM, EDX, FTIR, XRD. The methods used to characterize BT-Fe NPs. Then the particle supported on Attapulgite (ATP) was modified to synthesis of new nano particles - Green nano Fe / attapulgite (BT-Fe NPs/ATP). And the inspection of the removal of chromium (VI), 閾，

本文編號(hào)：1580565