糖作用下FeCl_3溶液中四方纤铁矿的形成及表征  

Formation and characterization of akaganéite in FeCl_3 solutions under the action of saccharides

作　　者：沈星宇 张必宪 熊慧欣[1] 徐轶群[1] 

机构地区：[1]扬州大学环境科学与工程学院,江苏扬州225127

出　　处：《扬州大学学报（自然科学版）》2017年第4期19-23,共5页Journal of Yangzhou University：Natural Science Edition

基　　金：国家自然科学基金资助项目(41472034;31372133;40902018);江苏省环境材料与环境工程重点实验室开放基金资助项目(K14022;K13058)

摘　　要：考察28℃下含适量糖(葡萄糖、鼠李糖、海藻糖、葡聚糖)的FeCl_3溶液水解反应中铁矿物的形成,并利用X射线衍射仪(XRD)、傅里叶红外光谱仪(FTIR)和场发射电子显微镜(FESEM)对产物进行表征.结果表明:Fe^(3+)与反应溶液中OH-在结合形成四方纤铁矿(β-FeOOH)沉淀的过程中,FeCl_3物质的量浓度宜为20mmol·L^(-1),葡萄糖浓度对β-FeOOH的形成速率无影响,而糖类的结构基团和相对分子质量大小对其有着明显的影响;糖所含—OH与Fe^(3+)、Fe(OH)^(2+)、Fe(OH)_2^+等之间的配位作用促进了FeOOH沉淀的形成和β-FeOOH的成核与生长;不同浓度或种类的葡萄糖作用下形成β-FeOOH产物的表面结构无明显差异,产物的颗粒形貌和尺寸大小也基本相似,均为纺锤形或棒状颗粒结构,颗粒粒径约为200~400nm,长宽比约为5.Formation of iron oxyhydroxide can usually be impacted by the organic substances such as saccharide extruded from bacteria in natural environments. In this work, the author observes the formation of iron precipitates in FeCl3 solutions containing moderate content of saccharides （such as glucose, rhamnose,trelalose,dextran 2w and dextran 4w） , during Fe^3＋ hydrolysis reaction for 8 days. The result product are identified and examined by X-ray diffraction （XRD） , Fourier trans-fer infrared spectrometer （FTIR） and field emission scanning electron microscopy （FESEM）. Results show that the moderate concentration of FeCl3 is 20 mmol·L^-1 for akaganeite （｜3-FeOOH） formation by ferric hydrolysis and neutralization with OH- , and saccharide concentration has little impact on the rate of ｜3_FeOOH formation, but which can markedly be influenced by the functional group and molecular structure of saccharides. The coordination action between -OH and Fe^3＋ , Fe（OH）^2＋ , or Fe（OH）^ can promote the formation of FeOOH by precipitation of ferric ions, nucle- ation and growth of β-FeOOH crystals. Under the function of various contents or kinds of saccha-rides ,the obtained β-FeOOH products present little changes in their surface structures and the sim-ilar morphology of spindle- or rod-shape particles with a length of 200^-400 nm with an axial ratio of about 5 are observed.

关 键 词：糖 四方纤铁矿 羟基氧化铁 

分 类 号：O614.81[理学—无机化学]