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1.
坡缕石/磁性铁氧化物/TiO2复合光催化剂性能实验研究   总被引:1,自引:0,他引:1  
用醇盐水解法、硫酸亚铁-硝酸钾氧化法制备TiO2光催化剂、坡缕石/TiO2复合光催化剂和坡缕石/磁性铁氧化物/TiO2复合光催化剂.通过XRD、TEM、UV-Vis和MS分析光催化剂的物相组成、形貌特征、对紫外可见光的漫反射以及磁化率,并以甲基橙为处理对象,对比研究了TiO2光催化剂、坡缕石/TiO2复合光催化剂和坡缕石/磁性铁氧化物/TiO2复合光催化剂的光催化效果.结果表明:坡缕石/磁性铁氧化物的复合能降低复合光催化剂中锐钛矿的平均粒径,提高锐钛矿的分散性.铁的复合是否提高光催化剂的光催化效率与催化剂的煅烧温度有关.坡缕石的复合对光催化剂的最佳煅烧温度有影响.  相似文献   

2.
采用酸性溶胶法制备掺铁-TiO2/膨润土复合光催化剂,利用XRD﹑IR等测试手段对其进行了表征。通过测试甲基橙溶液的脱色率和COD去除率对复合光催化剂的光催化活性进行了评价。结果表明,该催化剂有较高的催化氧化性能,在太阳光照射下,对pH=4﹑质量浓度为20 mg/L的甲基橙溶液进行降解时,其脱色率可达95%以上,COD去除率可达85%以上。该催化剂在经过200℃焙烧活化2.5 h后可多次重复利用。  相似文献   

3.
掺铁二氧化钛薄膜的自组装制备、表征与光催化性能研究   总被引:3,自引:0,他引:3  
李青霞  孙振亚  王婷 《矿物学报》2011,31(1):102-107
采用自组装方法于低温液相反应体系中成功制备出大尺寸二维纳米二氧化钛薄膜和掺铁二氧化钛薄膜。样品通过荧光发射光谱、拉曼光谱、高分辨透射电镜等方法进行表征,并研究了紫外光和可见光下Fe3+/TiO2纳米薄膜对甲基橙溶液(MO)的光催化降解过程,探讨了Fe3+对TiO2的光催化活性的影响。结果表明,此方法不需要高温煅烧即可得到高催化活性的金红石和锐钛矿混合型二氧化钛薄膜,以金红石为主。Fe3+掺杂明显提高了TiO2对甲基橙溶液的光催化降解效率:掺杂Fe3+浓度为0.5 mmol/L时光催化效果最优,且更利于较低浓度甲基橙溶液的降解,在紫外光和可见光下对初始浓度5 mg/L甲基橙溶液的降解率分别达到98.62%和89.24%。  相似文献   

4.
以硅烷偶联剂黏结剂,利用溶胶-凝胶法将TiO2(P25)负载在膨胀石墨上,利用XRD、EDS以及SEM等分析技术对TiO2/膨胀石墨复合材料进行表征;以橙黄Ⅱ为目标降解物,考察了TiO2/膨胀石墨复合材料光催化性能以及重复使用性能。结果表明:随着TiO2含量的增加,TiO2/膨胀石墨复合材料的光催化效率随之增加,对橙黄Ⅱ的光催化降解符合一级反应动力学方程,TiO2负载量为15%时,反应速率常数为0.387 h-1,高于P25的反应速率常数。TiO2/膨胀石墨复合物使用4次仍保持较高的光催化活性。  相似文献   

5.
采用溶胶-凝胶法制备TiO2/电气石复合光催化剂,通过光降解甲基橙实验考察复合光催化剂的活性,发现复合物中2%电气石的制备比例就可以显著提升TiO2降解有机物活性,降解率(0.5h)达99.87%,明显优于纯TiO2(0.5h)83.64%,提高了约20%。经XRD、BET、SEM等手段对样品进行分析得知:经800℃以下长时间热处理,电气石的结晶构造不变;900℃热处理使电气石结构破坏。SEM分析显示复合物中TiO2颗粒呈球簇状,均匀包覆在电气石表面形成颗粒膜层。  相似文献   

6.
采用微波处理方法合成了TiO2结晶体柱撑蒙脱石光催化材料,采用XRD、BET吸附和降解甲基橙实验分析了柱撑蒙脱石的结构、锐钛矿金红石晶相比例、比表面积和光催化性能。结果证实,微波功率与辐照时间等条件将影响材料的结构与性能;与传统加热方式比较,微波处理可获得锐钛矿相含量高的混晶TiO2;该TiO2柱撑蒙脱石具备优异的光催化性能。  相似文献   

7.
TiO_2-I~-/γFe_2O_3磁性复合催化剂的制备及性能   总被引:1,自引:0,他引:1  
以四氧化三铁、钛酸四丁酯和氢碘酸等为原料,采用溶胶-凝胶法制备了一种新型磁性复合催化剂TiO_2-I~-/γFe_2O_3.通过X射线衍射分析、热重差热分析、透射电镜以及红外光谱进行分析,研究了热处理时间、温度以及碘掺杂量对光催化剂性能的影响.结果表踢:最佳碘掺杂量为0.5%,烧结温度为400℃,最佳烧结时间为0.5 h,材料对甲基橙的降解率达99%,3次循环使用后甲基橙的降解率仍保持在80%.  相似文献   

8.
以微晶白云母为载体,钛酸丁酯为钛源,采用溶胶-凝胶法合成制备微晶白云母负载纳米TiO2光催化剂,然后用X射线衍射,扫描电镜等对微晶白云母负载TiO2光催化剂进行表征。再以微晶白云母负载纳米TiO2光催化剂对亚甲基蓝进行了光催化降解研究,特别针对有无紫外光照射条件下微晶白云母、纳米TiO2、微晶白云母/纳米TiO2等在亚甲基蓝溶液中的行为进行研究,结果表明:所制备的微晶白云母负载TiO2光催化剂对亚甲基蓝具有较好的光催化降解能力,1250目微晶白云母负载TiO2在紫外光照射下光催化反应4h,其降解率可达99%以上。  相似文献   

9.
以钛酸丁酯为前驱体,采用醋酸为酸催化剂制备TiO2溶胶,将制备的溶胶分别加入经表面活性剂十六烷基三甲基溴化铵改性的河北、临安、安吉、内蒙古膨润土中,制备有机-钛柱撑膨润土复合光催化剂,并对其进行XRD、SEM、BET表征。结果表明,TiO2插入了膨润土层间,并以锐钛矿型的晶形存在,制备的复合光催化剂仍有较好的层状结构,其比表面积均比相对应的不同产地的膨润土的比表面积大。以甲基橙为目标污染物,考察了有机-钛柱撑膨润土复合光催化剂的吸附性能和光催化活性,发现所制备的复合光催化剂具有较好的光催化活性,而且用不同的膨润土合成的催化剂的光催化活性差别很大。膨润土的化学组成和层状结构上的差异是复合催化剂吸附性能和光催化活性差别的主要原因。其中有机-钛柱撑临安膨润土复合光催化剂的光催化活性最好。  相似文献   

10.
采用阳离子表面活性剂十六烷基二甲基溴化铵对临安膨润上进行改性修饰,以钛酸丁酯和K2P1Cl6为前驱体,利用掺有小同量铂的TiO2溶胶对改性膨润土进行反应,制得一系列掺铂有机-钛柱撑膨润土复合材料。测定了复合材料的BET比表面积,利用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)和能量分散光谱(EDS)等手段对其微观结构进行了表征。以甲基橙染料为目标污染物,考察了复合材料的吸附能力和光催化活性。实验结果表明,掺铂的有机-钛柱撑膨润土复合材料比未掺铂的复合材料具有较好的层状结构,且对甲基橙的吸附能力较佳。由于铂能够充当捕获载流子的陷阱,能够有效抑制TiO2光生电子-空穴的复合,所以掺铂有机-钛柱撑膨润土复合材料具有更好的光催化性能,其中掺铂量为0.2%的复合材料的光催化活性最佳,对甲基橙的降解效果最好。  相似文献   

11.
河南省鲁山石墨矿浮选工艺研究   总被引:4,自引:0,他引:4  
河南鲁山石墨矿属区域变质型矿床.根据矿石性质,进行了粗选条件试验,阶段磨矿阶段选别试验和阶段磨矿阶段选别预先分目试验,研究结果表明阶段磨矿是保护石墨大鳞片的有效方法,同时,结合预先分目能更好地提高石墨大片率.阶段磨矿阶段选别预先分目工艺闭路试验获得的指标为:当原矿品位为3.65%时,获得的技术指标为精矿品位C90.62...  相似文献   

12.
山东蓝宝石的主要致色因素   总被引:1,自引:0,他引:1       下载免费PDF全文
山东蓝宝石颜色深暗,与其主要致色元素有着直接关系.对其化学成分进行分析认为:Cr2O3是红色、橙黄色、黄色的主要致色因素.而w(TiO2)低,w(TFeO)高,尤其是Fe3 大于全铁的90%,TFeO/TiO2比值大是山东蓝宝石颜色深暗的主要原因.对其紫外-可见光-近红外吸收光谱进行分析,进一步得出Cr3 离子的d-d电子跃迁、成对Fe3 离子、单Fe3 离子的d-d电子跃迁、Fe2 -Ti4 之间的电荷转移、Fe2 Fe3 之间的电荷转移等是山东蓝宝石致色的本质.代表绝大多数山东蓝宝石颜色的深蓝色蓝宝石,缺失紫外-可见光-近红外吸收光谱的575~711nm吸收带,即缺少Fe2 -Ti4 之间的电荷转移.因此,针对性地选择w(TiO2)高的蓝宝石进行改善,或是设法加入TiO2、减少Fe3 含量、在还原条件下改变其TFeO/TiO2的比值,应是目前山东蓝宝石改色的关键.  相似文献   

13.
A new organic hybrid of silicotungstic acid was prepared by means of an easily available, very cheap, and non-toxic amine via a facile precipitation method. Characterization of hybrid was carried out by elemental analyses, Fourier transform infrared spectroscopy, powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy. Dye adsorption and photocatalytic properties of the prepared water-insoluble hybrid were examined by studying the decolorization of model dyes such as methylene blue and methyl, orange and their mixture solutions under ultraviolet, visible, and sunlight irradiation. The effect of different factors containing the initial concentration, pH, catalyst dosage, H2O2 dosage, and salt adding was investigated on the decolorization of dyes. The results showed that the hybrid is a good heterogeneous photocatalyst in the degradation of methylene blue, methyl orange and their mixture and can be recovered and reused. The methylene blue is removed via combination of adsorption and photocatalytic degradation under ultraviolet, visible, and sunlight through direct oxidation by hybrid. The methyl orange is removed via ultraviolet and solar photocatalytic degradation through indirect oxidation by ·OH radicals. While the visible light is not able to degrade methyl orange solution alone in the presence of hybrid, it degrades the methyl orange mixed with methylene blue solution.  相似文献   

14.
采用微波法对蜜桔皮中黄酮类化合物进行提取。将单因素分析与正交试验相结合,得到微波法提取蜜桔皮中黄酮类化舍物的最佳工艺条件:提取剂乙醇体积分数为50%;微波功率为560w;提取时间为4min;料液比(g/mL)为1:30。每克蜜桔皮中提取黄酮类化合物为0.52mg,回收率为93.3%。在最佳参数组合下,桔皮黄酮提取量可这最大,并且研究了AB-8大孔吸附树脂对桔皮黄酮的吸附和解吸附特性和纯化效果,结果表明AB-8大孔树脂可用与桔皮中总黄酮的纯化。  相似文献   

15.
镉标准溶液配制结果的不确定度评定   总被引:4,自引:2,他引:2  
李松  饶竹 《岩矿测试》2009,28(5):479-482
选择氧化镉标准物质,配制成质量浓度为1000μg/mL的镉标准溶液,利用等离子体质谱法对标准溶液进行了定值与稳定性检验。通过对镉标准溶液配制过程不确定因素的描述,以95%概率下的扩展因子2获得标准溶液浓度配制标示值的扩展不确定度。实验数据表明,所配制的标准溶液稳定性可达2年。  相似文献   

16.
An iron (III)-impregnated sorbent was prepared from sugarcane bagasse and ferric chloride solution via carbonization/activation in a muffle furnace at 500?°C for 4?h. The adsorption removal of chromium (VI) from aqueous solution by the iron (III)-impregnated sorbent was then studied in a batch system. With increasing initial chromium (VI) concentration from 25 to 130?mg/L at an adsorbent dose of 300?mg/50?mL, the amount of adsorbed chromium (VI) increased from 4.15 to 12.20?mg/g at 20?°C, from 4.16 to 12.50?mg/g at 30?°C, and from 4.16 to 13.72?mg/g at 40?°C. The dynamical data fit very well with the pseudo-second-order kinetic model, and the calculated adsorption capacities of 4.16, 8.37, and 13.37?mg/g were equal to the actual values of the experiments at the initial chromium (VI) concentrations of 25, 50, and 100?mg/L, respectively. The Langmuir isotherm could yield better fits than the Freundlich isotherm. The calculated isotherm parameters confirmed the favorable adsorption of chromium (VI) on the iron (III)-impregnated sorbent.  相似文献   

17.
钒钛磁铁矿样品经过氧化钠熔融,盐酸提取,溶液分取稀释后用电感耦合等离子体发射光谱法同时测定其中的V2O5、TiO2、Co、Ni。实验确定过氧化钠的用量为1.5 g,盐酸的用量为10 mL,选择干扰元素较少和背景干扰较小的V、Ti、Co、Ni分析谱线分别为292.4 nm、334.9 nm、230.7 nm、231.6 nm,在稀释因子为10(总稀释因子5000)的条件下进行分析,方法检出限为0.05~0.17μg/g。用国家一级钒钛磁铁矿标准物质GBW 07225(原矿)、钒钛磁铁矿标准物质GBW 07226a(精矿)、钒钛磁铁矿标准物质GBW 07227(尾矿)验证方法精密度和准确度,方法精密度(RSD,n=12)为0.41%~1.91%;除含量较低的Ni和Co外,相对误差(RE,n=4)均小于5%。通过安装氩气加湿器有效地解决了盐分较大带来的影响,在标准系列中加入等量空白溶液,保持基体与试样一致,消除了基体效应。方法分解样品彻底完全,分析流程简单,易于掌握,一次熔样可以同时测定多种元素,可适用于大批量样品分析。  相似文献   

18.
淡水中丝状绿藻对重金属Pb2+的吸附   总被引:3,自引:0,他引:3  
通过淡水中绿藻门的一些丝状种类,如毛枝藻(Stigeoclonium)、刚毛藻(Cladophora)、水绵(Spirogyra)对铅的吸附实验,研究淡水藻类与铅的吸附关系及影响因素。结果表明,淡水中丝状绿藻对铅有较强的吸附能力, 当pH值和温度以及包埋藻类的量控制在一定条件下,即pH值约为4,温度为28℃左右,按照2 g藻类处理20 mL 质量浓度为100 mg/L Pb2+溶液原则包埋藻类,就可以使单位藻类吸附效率达到40%。  相似文献   

19.
The hydrated-titanium-oxide/montmorillonite composite samples were prepared using a hydrolysation- intercalation composite method by controlling the amount of TiOSO4·2H2O. The TiO2/montmorillonite composite samples were got after calculated at 700℃ and 1100 ℃. The results show that: when the value of Ti/montmorillonite is 12.5 mmol/g, the c axis of hydrated-titanium-oxide/ montmorillonite composite sample began to disorder, moreover, the crystal size of anatase is just 13.4nm in the TiO2/montmorillonite composite sample calculated at 700 ℃, and after calculated at 1100 ℃, the crystal size of anatase is 55.8 nm, and the relative content of anatase reaches the highest (55.7%). Compared with pure TiO2 nano-particle sample, TiO2/montmorillonite composite sample has a higher phase transition temperature from anatase phase to rutile phase and smaller crystal size of TiO2. Montmorillonite structure layer has a significant blocking effect on TiO2 phase transformation and grain growth, and the blocking effect reaches saturation when the value of Ti/montmorillonite is 12.5 mmol/g.  相似文献   

20.
Xianfeng large-scale lignite mining area, symbiotic diatomaceous earth mining area is the second largest diatomaceous earth mining in China with high organic matter content. The Xianfeng diatomaceous earth mining is a difficult development and utilization of low-grade diatomaceous earth, which has not been effective utilized due to low economic value of traditional processes. The objectives of this paper are utilizing high organic matter content diatomite as waste resources and improving the comprehensive utilization ratio of mineral resources in Xianfeng coal mining areas. The high organic content diatomaceous earth was purified by the acid washing and then calcinations under N2 as a protective atmosphere and high temperature of 500 to 800 ℃. The organic matter was carbonized with the formation of amorphous complex of activated carbon and diatomaceous earth. The novel ternary composited diatomaceous earth was prepared by combining carbonation diatomaceous earth and magnetic nanomaterials. The absorption property of ternary composited diatomaceous earth was improved through the organosilane and polyacrylamide modification to meet the needs of practical application. Electron microscopy showed that magnetic precursor calcined under N2 as a protective atmosphere, the surface of the magnetic nanoparticles were coated with amorphous carbon, which improved chemical stability and compatibility with diatomaceous earth. The magnetic nanoparticles and amorphous activated carbon uniformly dispersed in a diatomaceous earth surface and within the pores, to form a stable magnetic nanoparticles - the amorphous active carbon - ternary complexes. The specific surface area and methylene blue adsorption test showed ternary composited diatomaceous earth performing much higher than conventional diatomite products, the novel diatomaceous earth with specific surface area of 55.79 m2/g, methylene blue adsorption capacity of 44.5 m2/g. MgFe2O4 and Co3O4-based superparamagnetic ternary composited diatomaceous earth as an unique adsorbent has great application potential in organic pollutants and heavy metals pollution treatment of water. In addition, the CoFe2O4 based soft magnetic ternary composited diatomaceous earth has potential applications in magnetic plastics, rubber functional filler fields. This study shows that the proposed technology is conducive to a substantial increasing economic value of the Xianfeng diatomaceous earth mining, has a broad industrial application prospects.  相似文献   

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