本文關(guān)鍵詞： 鐵 四環(huán)素 絮凝 絡(luò)合物　出處：《湖南農(nóng)業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：四環(huán)素在畜禽養(yǎng)殖業(yè)中廣泛使用,其排放對(duì)水體環(huán)境產(chǎn)生嚴(yán)重的危害。本論文利用淀粉包覆的零價(jià)納米鐵(starch-NZVI)去除水體中的四環(huán)素(TC),研究了四環(huán)素初始濃度、pH,不同反應(yīng)時(shí)間,離子的類型,離子強(qiáng)度等因素對(duì)去除效果的影響。當(dāng)四環(huán)素原始濃度為500 mg/L,零價(jià)納米鐵0.20 g/L的時(shí)候,去除四環(huán)素的效率高達(dá)99%,其中吸附和降解占30%,絮凝作用占69%。零價(jià)納米鐵去除四環(huán)素容量隨著四環(huán)素的濃度升高而升高,當(dāng)四環(huán)素原始濃度為1000 mg/L,最大去除容量4137.3 mg/g。此外,從絮凝作用的來看,它受到pH和離子強(qiáng)度的影響非常大。中性條件和高鹽離子濃度可以提高去除效率和絮凝沉降速率。99%Fe-TC的絡(luò)合物一般在7天完成絮凝,在2M NaCl條件下,僅需要24小時(shí)。XPS分析顯示絮凝物中Fe由88%Fe(Ⅲ)和12%Fe(Ⅱ)組成。LC-MS顯示有機(jī)成分包括TC和它經(jīng)過氧化后的降解產(chǎn)物。我們的結(jié)果是首次報(bào)道零價(jià)納米鐵通過降解和絮凝的復(fù)合作用高效去除水中的四環(huán)素。為了快速去除水體中的四環(huán)素,我們發(fā)現(xiàn)Fe(Ⅲ)與四環(huán)素易形成帶正電荷的絡(luò)合物質(zhì),它能快速高效地被聚丙烯酸-丙烯酰胺復(fù)合樹脂吸附去除。通過研究材料中O=C-NH-C的數(shù)量、鐵離子與四環(huán)素含量比、鹽離子濃度對(duì)去除四環(huán)素效果的影響,結(jié)合最優(yōu)化條件下的吸附熱力學(xué)、吸附動(dòng)力學(xué)發(fā)現(xiàn)Fe(Ⅲ)能夠顯著促進(jìn)四環(huán)素被樹脂吸附,Fe(Ⅲ)的去除幾乎不受四環(huán)素影響。在500 min內(nèi),大量四環(huán)素被去除。初步探討出機(jī)理如下：Fe(Ⅲ)和TC先形成Fe-TC絡(luò)合物,然后被樹脂吸附,其中鐵離子具有橋梁作用,其具有大量空軌道,不僅與四環(huán)素有配位作用,而且與樹脂中的CONH2\ O=C-NH-C有配位作用,所以隨著樹脂中O=C-NH-C越多,去除四環(huán)素的效果越高。Fe(Ⅲ)、Fe-TC絡(luò)合物與羧基的反應(yīng)可能是離子交換作用,但是羧酸基因與鐵離子的相互作用力強(qiáng)，，會(huì)破壞Fe-TC絡(luò)合物結(jié)構(gòu),而形成COO-Fc(Ⅲ)的結(jié)構(gòu)。
[Abstract]:Tetracycline is widely used in livestock and poultry breeding, and its discharge has serious harm to the water environment. In this paper, the initial concentration of tetracycline (pH) and different reaction time were studied by using starch-NZVI (starch coated nano-iron) to remove tetracycline (TCN) from water. When the original concentration of tetracycline is 500 mg / L, and the zero valence nanocrystalline iron is 0.20 g / L, The efficiency of removing tetracycline is as high as 99mg / L, of which 30 are adsorbed and degraded, and 69 are flocculated. The removal capacity of tetracycline increases with the increase of tetracycline concentration, when the original concentration of tetracycline is 1000 mg / L, the maximum removal capacity of tetracycline is 4137.3 mg / g. From the point of view of flocculation, it is greatly affected by pH and ionic strength. Neutral conditions and high salt ion concentration can improve the removal efficiency and flocculation rate. The flocculation of 99-TC complex is generally completed in 7 days, and under the condition of 2m NaCl. It only takes 24 hours. XPS analysis shows that Fe in the flocculation consists of 88 (鈪

本文編號(hào)：1542753