水滑石焙烧产物对阴离子染料萘酚绿B的吸附动力学试验

研究了水滑石焙烧产物对萘酚绿B溶液的吸附动力学,考察了苯酚初始浓度和吸附剂投加量对吸附的影响,并用动力学模型进行了拟合。结果表明水滑石焙烧产物对萘酚绿B的吸附动力学过程可以用准二级模型进行描述。吸附平衡容量随着萘酚绿B初始浓度的增加、吸附剂投加量的降低而增加,而吸附速率随着萘酚绿B浓度的增加、吸附剂投加量的增加而降低。水滑石焙烧产物对萘酚绿B的吸附平衡遵循Langmuir等温线模型。颗粒内扩散模型分析表明水滑石焙烧产物在萘酚绿B溶液的吸附过程中,颗粒内扩散不是唯一的速率控制步骤。     

水滑石及其焙烧产物对水中苯甲酸根的吸附研究

为了脱除水中的苯甲酸根,以苯甲酸作为吸附质,研究了水滑石及其焙烧产物的吸附作用。考察了吸附剂的镁铝摩尔比、初始pH值、苯甲酸浓度、吸附剂添加量、吸附时间和温度对吸附效果的影响,并对比考察水滑石和焙烧水滑石对苯甲酸的吸附。结果表明,水滑石及其焙烧产物对苯甲酸的最优吸附条件均为酸性环境下,镁铝摩尔比3∶1,吸附质浓度220 mg/L,吸附剂的量0.06 g;水滑石吸附时间20 h,吸附温度为60℃时,对苯甲酸的去除效果最好;而焙烧水滑石在室温下吸附苯甲酸8 h达到最高去除率;在同样条件下,水滑石焙烧产物比水滑石对苯甲酸的吸附大得多。     

Mg-Al-Fe类水滑石及其焙烧产物对活性艳红X-3B脱色性能研究

采用共沉淀法合成出一系列镁铝铁不同量的比的碳酸根型类水滑石(HTLCs),经500℃高温煅烧制备出镁铝铁复合氧化物HTLCs-500,并用X-射线、红外光谱对它们进行表征;考查了吸附剂投加量、反应时间、初始pH等因素对二者处理阴离子染料活性艳红X-3B模拟废水效果的影响,并对吸附机理进行了探讨.结果表明:以镁、铝、铁的量比为3:0.6:0.4时制得的类水滑石对活性艳红X-3B溶液的脱色效果最好;HTLCs及其焙烧产物HTLCs-500对活性艳红X-3B染料均具有较好的吸附性能,在较宽的pH范围内2者的脱色性能稳定,且HTLCs-500对该染料的吸附效果要优于HTLCs;HTLCs及HTLCs-500对活性艳红X-3B的吸附结果符合Langmuir吸附等温式,25°下饱和吸附量分别为362.9、889.2 mg·g-1;饱和吸附后的HTLCs-500用高温热解法再生,吸附性能良好,随再生次数增多,脱色率下降.     

水滑石类材料及其对水中阴离子污染物的吸附

水滑石类材料,是一类由带正电荷层和层间填充带负电荷的阴离子所构成的层状化合物,因其独特的催化和吸附性能成功应用在化工、医药、农药、功能材料等领域,近年来,水滑石材料在环境领域的应用逐步成为研究热点,此类材料对水中无机阴离子、络合阴离子形式重金属离子、阴离子染料和阴离子表面活性剂有较强的吸附能力,显示出良好的应用前景。     

靛蓝胭脂红脱色酵母菌的筛选及研究

通过富集培养,从印染污水处理厂污泥中分离出四株靛蓝胭脂红脱色酵母,挑选其中脱色效果较好的酵母Y-1菌株进行摇瓶脱色研究。在染料浓度为60mg/L的条件下,此菌株在脱色14小时,对靛蓝胭脂红的脱色率达到95.85%。染料降解产物的紫外-可见光光谱分析表明,可见光区波长602nm处的吸收峰完全消失,紫外光区的吸收峰减弱。实验结果初步判断该酵母菌株对染料的脱色为生物降解作用。     

Zn-Al水滑石及其焙烧产物对水中磷的吸附研究

用水热法制备了不同尿素浓度下的Zn-Al水滑石,焙烧后制得焙烧态水滑石,用XRD、SEM 、BET、FTIR等方法对样品进行了表征,考察了水滑石及焙烧产物对水中磷酸盐的吸附性能.结果表明:水滑石对磷酸盐的吸附基本符合假二级动力学方程和Langmuir吸附等温式,当尿素浓度为0.6 mol/L,150℃水热24h,300...     

有机改性水滑石对染料废水的吸附处理研究

采用十六烷基三甲基溴化铵改性制得有机改性水滑石,并用XRD和红外光谱进行表征。考察了有机改性水滑石对染料废水的吸附能力及相关影响因素。结果表明,水滑石改性后对染料吸附能力提高,染料去除率随改性水滑石投加量的增加而提高,随染料初始浓度的增大而降低,温度太高不利于染料的吸附,p H对染料废水的处理效果影响不大。改性水滑石对染料的吸附可用Langmuir等温吸附方程拟合,二级吸附模型能很好地描述改性水滑石对染料的吸附行为。表征结果表明十六烷基三甲基溴化铵进入到水滑石层间,但水滑石结构并没有发生大的变化。     

焙烧态镁铝水滑石对刚果红的脱色性能研究

采用单滴法合成了n(Mg)/n(Al)=3的镁铝水滑石Mg3Al-LDH及其焙烧态产物Mg3Al-CLDH,并对刚果红溶液进行了吸附脱色试验。XRD分析结果说明合成的Mg3Al-LDH样品具有水滑石的典型结构,Mg3Al-CLDH在吸附刚果红阴离子后重新恢复为水滑石的层状结构。相同条件下Mg3Al-CLDH对刚果红的脱色率高于Mg3Al-LDH。对质量浓度为100mg/L的刚果红溶液,当Mg3Al-CLDH投加量为0.7g/L,pH值为5～10时,室温下反应40min,脱色率可达99%以上。Mg3Al-CLDH重复再生4次循环利用,刚果红脱色率仍在90%以上。表明Mg3Al-CLDH能够有效吸附溶液中的刚果红阴离子,可用于水体中阴离子染料的脱色处理。     

焙烧态锌镁铝水滑石吸附刚果红的性能研究

采用水热法制备锌镁铝水滑石前驱体,经500℃焙烧得到Zn-Mg-Al复合金属氧化物(ZnMgAl-LDO)吸附材料。通过XRD、SEM、FTIR等对其结构特征及形貌进行表征。以难降解的有机染料刚果红为模拟污染物,研究ZnMgAl-LDO的吸附性能,并对吸附过程的动力学和等温线进行了探讨。结果表明,在25℃,pH值为7.02条件下,40 mg的ZnMgAl-LDO对200 mL初始质量浓度为40 mg/L刚果红溶液的去除率为97.86%。ZnMgAl-LDO对刚果红的吸附过程符合准二级动力学模型和Langmuir等温吸附模型,为表面单分子层吸附。经3次循环使用后,对刚果红的去除率仍能达到90%以上。     

焙烧态锌镁铝水滑石吸附刚果红的性能研究

采用水热法制备锌镁铝水滑石前驱体,经500℃焙烧得到Zn-Mg-Al复合金属氧化物(ZnMgAl-LDO)吸附材料.通过XRD、SEM、FTIR等对其结构特征及形貌进行表征.以难降解的有机染料刚果红为模拟污染物,研究ZnMgAl-LDO的吸附性能,并对吸附过程的动力学和等温线进行了探讨.结果表明,在25℃,pH值为7....     

Removal of Indigo Carmine and Pb(II) Ion from Aqueous Solution by Polyaniline

In this work, we report the synthesis of polyaniline emaraldine salt (PAni-ES) by a chemical oxidative polymerization method. The obtained PAni-ES samples prepared under different conditions were used for the removal of indigo carmine anionic dye and Pb(II) ion from aqueous solutions. The results also showed that the pseudo–second-order kinetic model fitted better than the data obtained from pseudo–first-order model for the adsorption of anionic dye and Pb(II) ion onto PAni-ES. The fit of the data for indigo carmine and Pb(II) ion adsorption onto PAni-ES suggested that the Langmuir model gave closer fittings than Freundlich model.     

改性膨润土对污水中镉离子的吸附去除效率

采用内蒙赤峰膨润土进行焙烧改性,考查了改性膨润土对水溶液中Cd^2＋的吸附性能。试验表明：钙基膨润土经450℃焙烧2．5h后,在pH值=5,吸附时间为25min时,对金属Cd^2＋离子的饱和吸附效率达83％;焙烧前后XRD分析显示膨润土保持了完善的层间结构和化学结构。     

云芝菌发酵产漆酶及其对靛蓝脱色的研究

采用云芝菌(Coriolus versicolor)摇瓶发酵生产漆酶,对主要的工艺参数进行了优化.研究结果表明:木质纤维废弃物木糖渣可用作云芝菌产酶的有效碳源,其适宜浓度为20.0 g·L-1;在培养基中添加10 0 g·L-1葡萄糖可以促进菌种的前期生长,有利于发酵后期漆酶的分泌合成;产酶培养基的最适C/N为20;适量的Cu2 和维生素C对漆酶的生成有明显促进作用,其适宜浓度分别为0.100 mmol·L-1和1.500 mmol·L-1.3.7 L自控式发酵罐中的产酶试验显示:最适通气量为100 L·h-1.在云芝菌的发酵进程中,前期主要为营养生长,产酶高峰期出现在发酵后期.在优化条件下发酵144 h,漆酶活力可高达2474.2 IU·mL-1.采用上述粗酶液处理靛蓝染料,当靛蓝浓度为50 mg·L-1,粗酶液用量为0.45%(Ⅴ∶Ⅴ)时,反应40 min,脱色率可达到94.8%.试验结果显示,漆酶在牛仔服生物整理及染整废水的脱色净化处理中具有良好的应用前景.     

TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

Applications of carbon-TiO₂ materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO₂ on carbon prepared from residues of the plant Manihot, commercial TiO₂ and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant S_BET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO₂/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture.     

Kinetic Study of Leuco‐Indigo Carmine Oxidation and Investigation of Taylor and Dean Flow Superposition in a Coiled Flow Inverter

In two‐phase capillary flow, Taylor and Dean vortices can enhance mass transfer according to recent studies. By utilizing a colorimetric method based on the consecutive oxidation of leuco‐indigo carmine it is possible to visualize the superposition of Taylor and Dean vortices in a gas‐liquid system. A kinetic study is performed in order to estimate the enhancement factor. Depending on the flow conditions, three different flow regimes are identified with different intensities of Taylor and Dean vortices affecting the oxygen distribution within the liquid phase. A dimensionless number is derived that describes this transition in flow regimes.     

焙烧层状氢氧化镁铝吸附脱除水中苯酚的研究

用层状氢氧化镁铝的焙烧产物吸附水中苯酚,研究了吸附剂用量、吸附时间、温度、溶液pH值等条件对吸附性能的影响。结果表明,吸附主要发生在90min内,吸附量随着温度的升高而增加。溶液初始pH值对吸附影响较大,pH值在6～11范围内吸附效果较酸性时好。吸附符合Langmiur等温线,饱和吸附量为0.557mg/g。     

煅烧凹凸棒石的水化处理对其结构演化和吸附NH3的影响

采用X射线衍射分析了煅烧凹凸棒石的水化处理对其结构演化的影响;通过NH3吸附试验表征煅烧凹凸棒石水化处理后表面性质的变化,揭示了凹凸棒石对NH3的吸附机理。结果表明：随着煅烧温度的不断提高,凹凸棒石中的结晶水和结构水逐步脱除,内孔道结构发生折叠塌陷,凹凸棒石的内孔道折叠温度在250～300℃之间,只有低于300℃煅烧的...     

Perchlorate Uptake from Aqueous Solutions by Calcined Mg-Al Layered Double Hydroxides

The calcined layered double hydroxides (CLDHs) with 3:1 Mg/Al molar ratio were observed to acquire a high removal efficiency of perchlorate. And they were applied into perchlorate adsorption process with the initial 100 mg/L perchlorate solution in order to analyze removal efficiencies of perchlorate on various influential factors. The results represented that 1.5 g/L CLDHs could achieve ideal adsorption efficiencies of perchlorate at the pH range of 7–9 and at the temperature of 25°C. The removal efficiencies of perchlorate increased up to a maximum efficiency with the increasing dose of CLDHs. Acidic or highly alkaline environment adversely affected perchlorate adsorption. The adsorption process was found to be endothermic due to the higher adsorption capacity in CLDHs with the increasing temperature. The removal of perchlorate was best represented by the pseudo second-order kinetics model and Langmuir isotherm model. Co-existing anions tests showed that the anions of higher valence had a more significant effect than the monovalent anions during the adsorption process. Finally, the adsorption process was further validated by the X-ray patterns and Fourier-transform Infrared spectra of CLDHs. Results demonstrated potential utility of CLDHs that could be developed into a viable technology for perchlorate removal from water.