目录
摘要Ⅱ
关键词Ⅱ
AbstractⅢ
引言
引言1
1 材料与方法4
1.1化学试剂与仪器 4
1.2 SFeCuLaO的合成5
1.3溶液的配制5
1.4 As(III)吸附实验6
1.5 As(III)浓度的测定方法7
1.6等电点的测定方法7
2 结果与分析8
2.1初始pH对吸附的影响8
2.2竞争阴离子对吸附的影响9
2.3 .SFeCuLaO吸附As(III)的热力学研究10
2.4 .SFeCuLaO吸附As(III)的动力学研究12
2.5 .SFeCuLaO去除As(III)的机理探讨13
3 结论与讨论 15
3.1结论15
3.2讨论15
致谢15
参考文献16
磁性基掺硫铁铜镧三元金属复合氧化物去除水中As(III)的效果研究
摘 要
砷是一种广泛存在于自然界中的非金属元素。单质砷不具有毒性，但砷化合物均有毒，三价砷的毒性高于五价砷。砷污染对人体健康和生态环境都会造成严重危害。本文利用化学共沉淀法合成了吸附材料——磁性基掺硫铁铜镧三元金属复合氧化物（SFeCuLaO），研究了初始pH和竞争阴离子对SFeCuLaO吸附As(III)的影响以及吸附过程热力学和动力学方程行为，并通过通入氮气和添加不同自由基抑制剂简单探讨了As(III)的吸附机理。结果表明，在As(III)初始浓度为30 mg/L、SFeCuLaO用量为0.2 g/L的条件下，随着初始pH在3.010.0范围内不断增大，As(III)的去除率先增加后减小，在pH=6.0时达到最大值。在研究的五种竞争阴离子中，PO43(对As(III)吸附的抑制作用十分明显，而Cl(、NO3(、SO42(、CO32(对As(III)去除所产生的影响可以忽略。在初始pH为6.0、SFeCuLaO用量为0.2 g/L的条件下，测得材料的最大吸附量为188.24 mg/g。根据热力学模型拟合，此吸附过程符合Langmuir等 *51今日免费论文网|www.51jrft.com +Q: ￥351916072￥ 
温吸附模型，属于单分子吸附；根据动力学方程拟合，该吸附过程属于准二级反应。加入对苯醌和通入氮气对As(III)吸附抑制作用均很强，而加入叔丁醇对As(III)吸附基本上没有影响，说明在吸附过程中产生超氧自由基（O2•(），推测As(III)先被生成的O2•(氧化为As(V)，然后被SFeCuLaO吸附。
EFFICENT REMOVAL OF As(III) FROM AQUEOUS SOLUTION BY MAGNETIC SULFURDOPED IRONCOPPERLANTHANUM TRIMETALLIC OXIDES
ABSTRACT
Arsenic is a kind of nonmetallic element, which widely exists in the environment. Arsenic itself has no toxicity, but its compounds are all toxic, and the toxicity of As(III) is much higher than As(V). The pollution of arsenic in water is extremely harmful to human health and ecological environment. The adsorbent material, magnetic sulfurdoped FeCuLa trimetallic oxide (SFeCuLaO) was successfully synthesized by a chemical coprecipitation method. The effects of initial pH and competing anions were investigated in this paper, and the thermodynamic and kinetic equations were fitted for the adsorption process as well. The adsorption mechanism was proposed by degassing with nitrogen and adding different free radical inhibitors. The results indicated that the removal efficiencies of As(III) gradually increased to the maximum value at pH 6.0 and then decreased with the initial pH increasing in the range of 3.010.0 when the initial concentration of As(III) was 30 mg/L and the adsorbent dosage was 0.2 g/L. Among the five competing anions studied, the presence of PO43( obviously inhibited the adsorption of As(III), while the influences of Cl(, NO3(, SO42( and CO32( on the removal of As(III) could be ignored. The maximum removal capability for As(III) reached 188.24 mg/g with 0.2 g/L SFeCuLaO at pH 6.0. The adsorption of As(III) was well fitted by Langmuir isotherm model and the pseudosecondorder kinetic model. The introduction of pbenzoquinone (BQ) and N2 perfromed a strong inhibition effect while the addition of tertbutanol (TBA) has no effect on the adsorption of As(III), suggesting that As(III) was oxidized to As(V) by the generated O2•(, and then the produced As(V) was adsorbed onto the surface of SFeCuLaO.

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