本文選題：零價(jià)鐵 + 弱磁場(chǎng)�。� 參考：《山東大學(xué)》2015年碩士論文

【摘要】：重金屬?gòu)U水的排放已經(jīng)給環(huán)境和人體健康造成了嚴(yán)重威脅,重金屬污染問(wèn)題目前已成為環(huán)境領(lǐng)域的熱點(diǎn)和難點(diǎn)問(wèn)題。其中鉻(Cr)和銻(Sb)被廣泛應(yīng)用于國(guó)民經(jīng)濟(jì)的各個(gè)領(lǐng)域,其開采、冶煉和加工已經(jīng)導(dǎo)致了嚴(yán)重的水污染。近二十年來(lái),零價(jià)鐵(zero-valent iron, ZVI)被廣泛應(yīng)用于修復(fù)地下水或者去除含各種有機(jī)無(wú)機(jī)污染物的工業(yè)廢水。但ZVI的應(yīng)用仍然存在一些技術(shù)上的缺陷,其中包括：鐵粉表面帶有生產(chǎn)過(guò)程中產(chǎn)生的鈍化層,反應(yīng)活性較低；有效pH范圍窄；且隨著反應(yīng)時(shí)間的推移,生成的金屬鐵氧化物和碳酸鹽覆蓋在ZVI表面造成鈍化,反應(yīng)活性降低；對(duì)某些難降解污染物的處理效果較差,該技術(shù)仍然存在需要改進(jìn)的地方。為此,本文分別采用活性炭負(fù)載納米零價(jià)鐵(NZVI/AC)技術(shù)以及弱磁場(chǎng)(WMF)與ZVI聯(lián)用技術(shù)分別去除水中Cr(Ⅵ)和Sb(Ⅲ)。具體如下：(1)對(duì)NZVI/AC去除水中Cr(Ⅵ)考察了ZVI負(fù)載量、NZVI/AC投加量、溶液初始pH、反應(yīng)溫度以及Cr(Ⅵ)初始濃度等各種影響因素對(duì)處理效果的影響,探討了NZVI/AC去除水中Cr(Ⅵ)的作用機(jī)理。實(shí)驗(yàn)結(jié)果表明：NZVI/AC能夠高效去除水中的Cr(Ⅵ),其機(jī)理為吸附、還原和共沉。將NZVI負(fù)載在AC上,可以減少鐵顆粒的團(tuán)聚,提高材料的比表面積,從而提高NZVI的性能。NZVI負(fù)載量對(duì)去除效果有一定的影響,負(fù)載量為25%時(shí)去除效果最好,去除率達(dá)90%以上；溶液初始pH對(duì)NZVI/AC去除水中Cr(Ⅵ)的影響最為顯著,在pH=3.0-9.0范圍內(nèi),Cr(Ⅵ)的去除率隨溶液初始pH值的升高而下降；升高溫度有利于反應(yīng)的進(jìn)行；Cr(Ⅵ)濃度的增加不利于反應(yīng)的進(jìn)行；在不同反應(yīng)溫度和不同Cr(Ⅵ)濃度下,NZVI/AC去除水中Cr(Ⅵ)的反應(yīng)符合偽一級(jí)動(dòng)力學(xué)模型；反應(yīng)后溶液中基本無(wú)Cr(Ⅲ)和鐵離子,不會(huì)造成二次污染。(2)用WMF輔助ZVI去除水中Sb(Ⅲ),研究了在不同pH條件下、不同初始Sb(Ⅲ)濃度下以及一些陰離子存在時(shí)WMF對(duì)ZVI去除Sb(Ⅲ)的影響,并對(duì)反應(yīng)后的材料進(jìn)行了XAFS表征。實(shí)驗(yàn)結(jié)果表明：WMF輔助ZVI去除水中Sb(Ⅲ)時(shí),大部分的Sb(Ⅲ)被氧化為Sb(V)。在較寬的pH范圍內(nèi)和較高的初始Sb(Ⅲ)濃度下,磁場(chǎng)都能顯著加速ZVI去除水中Sb(Ⅲ)。ZVI對(duì)Sb(III)的去除受ZVI腐蝕速度的影響,與溶解在溶液中的Fe2+濃度和溶液的pH密切相關(guān),WMF的引入極大地促進(jìn)了ZVI的腐蝕速率。硝酸根和氯離子對(duì)ZVI去除Sb(Ⅲ)幾本上沒(méi)有影響,亞砷酸鹽、磷酸鹽和硅酸鹽在一定程度上,降低了Sb(Ⅲ)的去除效率。
[Abstract]:The discharge of heavy metal wastewater has posed a serious threat to the environment and human health. Heavy metal pollution has become a hot and difficult problem in the field of environment.Among them, Cr (Cr) and SB) are widely used in various fields of national economy. Their mining, smelting and processing have resulted in serious water pollution.In the past two decades, zero-valent iron zero-valent iron (ZVI) has been widely used in the remediation of groundwater or the removal of industrial wastewater containing various organic and inorganic pollutants.However, the application of ZVI still has some technical defects, including: the surface of iron powder has passivation layer produced in the production process, the reaction activity is low, the range of effective pH is narrow, and the reaction time goes on.The metal iron oxides and carbonates are passivated on the surface of ZVI, and the reaction activity is decreased. The treatment effect of some refractory pollutants is poor, and there are still some improvements in the technology.Therefore, the activated carbon supported nanocrystalline NZVI / AC technique and the weak magnetic field WMF / ZVI technique were used to remove Cr (鈪，

本文編號(hào)：1737234