本文選題：改性硅砂 + 磷酸根��； 參考：《濟南大學》2017年碩士論文

【摘要】：含磷、氟的廢水是當前環(huán)境污染的重要組成部分。吸附法是去除廢水中磷和氟常用的方法之一。實驗通過在硅砂表面構建多孔二氧化硅包覆層,氨基功能化后再負載金屬離子以制備改性硅砂,并吸附水溶液中的磷酸根和氟離子。實驗還利用了氨基功能化的硅砂處理實際電鍍含銅廢水后再吸附磷和氟。論文為處理廢水中金屬離子以及磷、氟提供了新的思路。實驗采用模板法與溶膠-凝膠法相結(jié)合,以正硅酸四乙酯為硅源、十六烷基三甲基溴化銨為模板劑在堿性條件下,在硅砂表面形成多孔SiO2包覆層,此包覆硅砂經(jīng)N-(β-氨乙基-γ-氨丙基)甲基二甲氧基硅烷功能化并負載金屬離子(Fe、Al、Cu)進行改性,得到三種改性硅砂(Fe(III)-NH2-sand、Al(III)-NH2-sand、Cu(II)-NH2-sand)。采用FTIR、氮氣等溫吸附和火焰原子吸收光譜等手段對改性硅砂進行了表征。實驗研究了三種改性硅砂對磷和氟的吸附,探究pH值、反應溫度、時間、初始離子濃度對吸附效果的影響,從而確定了最佳吸附條件。三種硅砂對磷、氟的吸附過程均符合Langmuir模型和準二級動力學方程。通過三種改性硅砂對磷進行吸附,Fe(III)-NH2-sand吸附磷酸根的最佳pH值為4,當磷酸根的離子濃度為200mg/L,吸附時間為180min,吸附溫度為65℃時,最大吸附量為7.2mg/g。Al(III)-NH2-sand對磷酸根吸附的最佳pH為2,當磷酸根的離子濃度為100mg/L,吸附時間為90min,吸附溫度為65℃時,最大吸附量為2.5mg/g。Cu(II)-NH2-sand對磷酸根的吸附最佳pH值為2,當磷酸根的濃度為100mg/L,吸附時間達到120min,吸附溫度為65℃時,最大吸附量為2mg/g。三種改性硅砂吸附氟離子,實驗表明Fe(III)-NH2-sand吸附氟離子的最佳pH值為2,當氟離子的濃度為120mg/L,吸附時間達到90min,吸附溫度為65℃時,最大吸附量為5.1mg/g。Al(III)-NH2-sand對氟離子吸附的最佳pH為5,當氟離子的濃度為200mg/L,吸附時間為90min,吸附溫度為65℃時,最大吸附量為4.3mg/g。Cu(II)-NH2-sand對氟離子的吸附最佳離子pH值為4,當氟離子的濃度為100mg/L,吸附時間達到60min,吸附溫度為65℃時,最大吸附量為1.2mg/g。三種改性硅砂對于磷和氟的的吸附效果對比發(fā)現(xiàn):Fe(III)-NH2-sandAl(III)-NH2-sandCu(II)-NH2-sand。實驗利用氨基功能化硅砂對實際電鍍含銅廢水進行吸附,并將吸附后的硅砂分別用于去除磷酸根和氟離子,經(jīng)過四次連續(xù)吸附后,溶液中的磷、氟分別達到了國家排放要求,實現(xiàn)了一種雙重凈化廢水的模式。
[Abstract]:Wastewater containing phosphorus and fluorine is an important part of current environmental pollution. Adsorption is one of the commonly used methods to remove phosphorus and fluorine from wastewater. In this experiment, porous silica coating layer was constructed on the surface of silica sand. After amino functionalization, metal ions were loaded to prepare modified silica sand, and phosphate and fluorine ions were adsorbed in aqueous solution. Amino-functionalized silica sand was used to treat copper-containing wastewater and then to adsorb phosphorus and fluorine. This paper provides a new idea for the treatment of metal ions, phosphorus and fluorine in wastewater. In this experiment, a porous Sio _ 2 coating layer was formed on the surface of silica sand with tetraethyl orthosilicate as silicon source and hexadecyltrimethylammonium bromide as template under alkaline conditions. The coated silica sand was functionalized by N- (尾 -aminoethyl- 緯 -aminopropyl) methyl dimethoxy silane and modified with metal ions (Fe (III) -NH _ 2-NH _ 2-sand Al (III) -NH _ 2-sandU Cu (II) -NH _ 2-sand). The modified silica sand was characterized by FTIR, nitrogen isothermal adsorption and flame atomic absorption spectrometry. The effects of pH, reaction temperature, time and initial ion concentration on the adsorption of phosphorus and fluorine were studied. The adsorption process of phosphorus and fluorine by three kinds of silica sand is in accordance with Langmuir model and quasi second order kinetic equation. The optimum pH value of phosphate adsorbed by three kinds of modified silica sand is 4. When the ion concentration of phosphate is 200 mg / L, the adsorption time is 180 min and the adsorption temperature is 65 鈩，

本文編號：2063073