共查询到19条相似文献,搜索用时 156 毫秒
1.
2.
《合成材料老化与应用》2017,(4)
制备了钼钒改性高岭土催化剂,采用红外光谱(FTIR)、X射线衍射分析(XRD)及差示扫描量热(TG-DSC)手段对催化剂进行了表征,并将催化剂用于电化学处理焦化废水中。研究表明:高岭土经改性后,高岭土中的Al-O八面体结构部分被破坏,Al-O-Si的伸缩振动发生畸变形成了Si-O-Mo或Si-O-V键,使得高岭土的层间距显著增大;改性高岭土负载铁离子电化学处理焦化废水,p H值为4时,COD去除率达到84%。 相似文献
3.
4.
5.
采用N2吸附、IR酸性表征和SEM等手段研究碱改性或酸改性高岭土的孔体积、比表面积、酸性及形貌特征。采用改性后高岭土部分替代高岭土制备FCC催化剂,并利用ACE对制备的3种催化剂进行性能评价对比。结果表明,高岭土经过酸碱改性后,碱改性高岭土的孔体积为0.30 mL·g-1,比表面积为111 m2·g-1;酸改性高岭土的孔体积为0.27 mL·g-1,比表面积为146 m2·g-1,孔体积和比表面积均有大幅提高,表现出一定的L酸酸性。改性后高岭土部分替代高岭土制备的FCC催化剂抗重金属污染能力较强,重油转化能力提高,碱改性高岭土制备的催化剂活性更高,但焦炭产率较高。 相似文献
6.
采用水热法制备了钒酸铋催化剂,以罗丹明B为目标降解物,对催化剂的光催化性能进行了测定。考察了水热反应pH、反应温度、反应时间对催化剂光催化性能的影响,实验得出制备钒酸铋催化剂的最佳水热反应条件:水热反应pH为7、反应温度为100℃、反应时间为8 h。在最佳水热反应条件下,投放5 mg的钒酸铋催化剂,对5 mL初始质量浓度为10 mg/L罗丹明B溶液的光催化降解率高达96.5%。最后利用X射线衍射(XRD)表征手法,对最佳水热反应条件下制备的钒酸铋催化剂的结构进行了表征,证明制得的钒酸铋催化剂纯度较高。 相似文献
7.
硅烷偶联剂对龙岩高岭土表面改性的研究 总被引:1,自引:0,他引:1
采用硅烷偶联剂KH-540对龙岩高岭土进行表面改性处理,研究了偶联剂的用量、表面改性处理的pH值、改性温度、反应时间等因素对高岭土活化指数的影响。以高岭土在液体石蜡中的沉降体积和红外光谱(FT-IR)等手段研究了改性效果以及改性剂与高岭土之间的相互作用。结果表明,改性的最佳实验条件为:偶联剂用量为2%左右,改性pH在8~10,改性温度为60℃,反应时间40 min。高岭土经过活化处理后,在液体石蜡中的分散性和稳定性均得到明显提高;偶联剂与高岭土之间以化学键合作用为主。 相似文献
8.
9.
10.
采用等体积浸渍法制备不同系列钒-钨-钛催化剂,以与二噁英TCDD化学结构式相似的邻二氯苯作为替代物,研究催化剂对邻二氯苯的去除效率,考察钒负载质量分数和钨负载质量分数对邻二氯苯催化氧化性能的影响,通过XRD和催化剂比表面积分析对催化剂的微观结构进行表征。结果表明,随着钒负载质量分数的增加,催化剂比表面积降低,催化剂性能降低;随着钨负载质量分数的增加,催化剂比表面积增加,催化剂性能提高。钨的加入有利于促进活性钒的分散,提高催化剂的比表面积,催化剂比表面积是影响催化剂性能的关键因素。 相似文献
11.
Hongzhu Ma Qiongfang Zhuo Bo Wang 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,155(1-2):248-253
The electrochemical oxidation of methylene blue (MB) wastewater assisted by Fe2O3-modified kaolin in a 200 mL electrolytic batch reactor with graphite plate as electrodes was investigated. The catalyst was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of pH, current density and introduction of NaCl on the efficiency of the electrochemical degradation process were also studied. It was found that Fe2O3-modified kaolin has higher catalytic activity in the electrochemical degradation of MB wastewater. 96.47% chemical oxygen demand (COD) removal was obtained in 40 min of electrochemical treatment of MB wastewater at pH 3, current density was equal to 69.23 mA cm−2. 相似文献
12.
13.
生物吸附法是一项处理重金属离子废水污染的新技术,在处理重金属污染废水和重金属回收方面有着广阔的应用前景,具有较好的经济价值和社会效益。本文主要研究改性笋壳为吸附剂去除废水中的铬离子,探讨振荡时间、吸附剂量、初始浓度、温度、pH对铬离子去除率的影响。结果表明:pH对铬离子去除率有很大影响,pH越低,吸附效果越好。当笋壳用量为0.5 g,、振荡时间为90 min,铬离子吸附率可达40%以上。 相似文献
14.
15.
A novel carbon ceramic electrode consisting of CuNPs and MWCNT was developed to treat reactive orange 84 (RO84) wastewater using ultrasound-assisted electrochemical degradation. The proposed electrode generated more hydroxyl radicals than non-nanoparticle electrodes did. In addition, a new electrochemical sensor was applied to determine residue RO84 in an aqueous medium during discoloration. This sensor is based on a glassy carbon electrode modified with gold nanourchins and graphene oxide and can detect RO84 concentration in the range of 1.0-1200 μmol·L-1 with the detection limit of 0.03 μmol·L-1. The degradation effects of the modified electrode on RO84 were evaluated systematically with different initial pH values, time durations, and amounts of CuNPs and MWCNT. The results suggested that the removal efficiency of RO84 was approximately 83% after 120 min of electrolysis in a phosphate buffer with pH 8.0 using a carbon ceramic electrode made with 4.0 wt% CuNPs and 4.0 wt% MWCNT. The possible mechanism of RO84 degradation was monitored by gas chromatography-mass spectrometry, and degradation pathways were proposed. 相似文献
16.
17.
用循环伏安法制备DL-精氨酸/石墨烯修饰玻碳电极,研究金属铅在修饰电极上的电化学行为。在0.1 mol/L pH=4.5的NaAc-HAc缓冲液中,以DL-精氨酸/石墨烯修饰电极作为工作电极,用循环伏安法测定-1.0~1.0 V处的溶出峰电流。实验结果显示:铅的浓度与溶出峰电流具有良好的线性关系,范围是3.0×10-9~9.0×10-7mol/L,检测限为1.0×10-10mol/L,用于测定金属结果满意。 相似文献
18.
为探寻硝基芳香族有机污染物的高效降解技术,采用溶胶凝胶法制备了钛基锡系阳极,且掺杂Sb、La等元素对该电极材料进行了改性,并把该系列电极用于电化学处理模拟对硝基苯酚废水。通过SEM和XRD对电极形貌进行表征,分析了元素掺杂改善电极性能的机理,考察了电解条件对电化学降解对硝基苯酚效果的影响,探究了电场因素对电化学体系降解废水的影响机制。通过紫外吸收光谱分析推断了对硝基苯酚在电化学作用下可能的降解历程。研究结果表明:同时掺杂La和Sb的电极降解对硝基苯酚效果最好;在电解电压12 V、极板间距25 mm、pH值为7、电解质浓度0.5 mol/L的条件下电解120 min,对硝基苯酚的降解率可达92.8%,可见应用掺杂La、Sb的Ti/SnO2电极材料的电化学法降解对硝基苯酚优势相当明显。 相似文献
19.
An enhanced ozonation process, methylene blue (MB) wastewater treated by MnO2/O3 assisted with kaolin in a slurry reactor, at room temperature and atmospheric pressure, MB wastewater can be effectively purified, a chemical oxygen demand (COD) of 88.3% and a decoloration rate of 98.9% were obtained in 10 min at pH 11. Compared with MnO2/O3 catalytic ozonation (16.0% of decoloration and 33.3% of COD reduction), decoloration and COD reduction were markedly increased, indicating that kaolin can significantly improve the catalytic ozonation process. According to the experimental results, the hypothetical mechanism of degradation and the reaction kinetics were also proposed. COD reduction can be described by a second-order model and the reaction rate constant in the presence of kaolin was higher than that of absence of kaolin. 相似文献