基于H3PMo12O40修饰一例MOF复合材料实现阳离子染料吸附

采用溶剂热法,以H3PMo12O40和金属有机骨架（(Cu3(BTC)2, BTC=1,3,5-benzenetricarboxylate)为原料构筑一例金属有机骨架复合材料{H3PMo12O40@Cu3(BTC)2}?xG (G＝客体分子),并采用IR、XRD、SEM、TG、BET等手段进行了表征。研究其对水溶液中亚甲基蓝(MB)的吸附性能,并探讨了初始pH,温度,不同初始浓度的MB对吸附容量的影响。结果表明降低温度和降低溶液的初始pH值有利于亚甲基蓝的吸附。等温吸附模型符合Langmuir等温吸附模型,动力学符合拟二级动力学。热力学参数ΔG<0,ΔΗ<0和ΔS>0,表明H3PMo12O40@Cu3(BTC)2对亚甲基蓝的吸附是自发和放热的,而且对甲基紫、罗丹明B、孔雀石绿、碱性品红等阳离子染料有良好的吸附性能。     

Mn_(0.8)Cu_(0.2)Fe_2O_4/埃洛石纳米管的制备及其对次甲基蓝的吸附研究

采用溶胶凝胶法,以埃洛石纳米管、硝酸铁、硝酸锰、氯化铜为原料,制备磁性埃洛石纳米管,并采用扫描电镜,对Mn0.8Cu0.2Fe2O4/埃洛石纳米管磁性复合材料的形貌及结构进行分析,并对其吸附次甲基蓝废水进行研究。结果表明,磁离子很好的负载到埃洛石纳米管的表面,当投加量为0.1 g时,初始浓度为50 mg/L的溶液,去除率在90%以上,吸附量为11.61 mg/g,温度和浓度对磁性复合材料的吸附性能也有一定影响,吸附量随温度的升高及浓度的增大都呈增大趋势。     

Bi2O3光催化氧化降解亚甲基蓝的动力学研究

以Bi2O3作为光催化剂,进行了亚甲基蓝光催化氧化降解的动力学研究,得出亚甲基蓝降解的动力学方程,并利用L-H方程研究亚甲基蓝的降解,讨论了亚甲基蓝初始浓度、催化剂用量、溶液pH值和H2O2用量对光催化降解速率的影响。     

基于H_3PMo_(12)O_(40)修饰一例MOF复合材料及对染料的吸附

采用溶剂热法,以H3PMo12O40和金属有机骨架〔Cu3(BTC)2,BTC=均苯三甲酸根〕为原料构筑一例金属有机骨架复合材料〔H3PMo12O40@Cu3(BTC)2〕·x G(G=客体分子),并采用IR、XRD、SEM、TG、BET进行表征。研究其对水溶液中亚甲基蓝(MB)的吸附性能,并探讨了初始p H、温度、不同初始浓度的MB对吸附容量的影响。结果表明降低温度和降低溶液的初始p H值有利于亚甲基蓝的吸附。等温吸附模型符合Langmuir等温吸附模型,动力学符合拟二级动力学。热力学参数ΔG0,ΔΗ0和ΔS0,表明H3PMo12O40@Cu3(BTC)2对亚甲基蓝的吸附是自发和放热的,除此之外对甲基紫、罗丹明B、孔雀石绿、碱性品红等阳离子染料也有良好的吸附性能。     

基于三维框架材料H3PW6Mo6O40/Zn(BDC)(4,4'-Bipy)0.5高效吸附亚甲基蓝

采用溶剂热法,用H3PW6Mo6O40对金属有机骨架Zn(BDC)(4,4'-Bipy)05进行改性,制备出金属有机骨架复合材料H3PW6Mo6O40/Zn(BDC)(4,4'-Bipy)0.5.利用IR、XRD、TG、SEM对其结构进行分析.同时,以亚甲基蓝溶液模拟染料废水进行吸附实验,考察了初始pH、温度对吸附容量的影响,探究了其吸附等温线和动力学特征.实验结果表明,H3PW6Mo6O40/Zn(BDC)(4,4'-Bipy)05对亚甲基蓝有很好的吸附性能,在20℃和pH 2的条件下,吸附量达588.24mg/g,且该吸附符合Langmuir等温吸附模型和拟二级动力学方程,吸附过程自发且放热.     

石墨烯/二氧化钛复合材料的制备及其对亚甲基蓝的吸附性能研究

伴随着染料需求量增加,染料废水处理一直备受关注。物理吸附法是染料废水处理工艺中研究最广泛的方法之一,它是通过将污染物富集在材料表面,达到去除废水中污染物的目的。本文以鳞片状石墨为碳源,以TiO_2为钛源,通过水热法制备了石墨烯/二氧化钛(GN/TNT)复合材料,分析了pH值、吸附温度、溶液初始浓度、GN/TNT用量等因素对亚甲基蓝吸附性能的影响。结果表明亚甲基蓝溶液初始浓度为15mg/L,GN/TNT复合材料加入量为0.55g/L,吸附温度为328K,pH=10时,亚甲基蓝溶液脱色率可达91%,说明GN/TNT复合材料对亚甲基蓝具有良好的吸附能力。     

Mn3O4@SiO2核壳磁性复合材料对钼(VI)的吸附性能

采用氧化法和正硅酸乙酯水解法制备了Mn3O4@SiO2核壳结构磁性纳米材料，研究了其对水溶液中Mo(VI)离子的吸附效果。运用Ｘ射线衍射仪(XRD)、扫描电镜(SEM)、透射电镜(TEM)、红外光谱仪(IR)及磁强计(VSM) 等多种手段对Mn3O4@SiO2核壳磁性复合材料进行了表征,并研究了溶液的初始pH、Mo(VI)离子初始浓度和温度对Mo(VI)吸附量的影响。结果表明：在298 K条件下Mn3O4@SiO2核壳结构磁性复合材料对Mo (VI)的饱和吸附量为145.35 mg/g； Mn3O4@SiO2对Mo (VI)的吸附过程符合Langmuir等温吸附模型，吸附动力学符合准二级动力学模型；吸附热力学分析表明Mn3O4@SiO2复合材料对Mo (VI) 的吸附行为是自发的、放热过程。     

磁性半纤维素接枝聚丙烯酰胺凝胶对亚甲基蓝的吸附研究

利用自由基聚合和原位共沉淀法制备了1种磁性半纤维素接枝聚丙烯酰胺凝胶,研究了该凝胶吸附亚甲基蓝的性能,特别考察了凝胶用量、pH、吸附时间、亚甲基蓝初始含量等因素对吸附的影响。结果表明,磁性凝胶用量增大,凝胶单位吸附量下降;pH增大,凝胶吸附量增加;初始亚甲基蓝的质量浓度从25 mg/L增加到250 mg/L,凝胶吸附量不断增大。凝胶吸附亚甲基蓝的动力学符合准2级动力学方程,Langmuir、Freundlich和Temkin吸附等温线模型均能很好地拟合凝胶对亚甲基蓝的吸附过程。     

高岭土对染料废水中亚甲基蓝的吸附去除

利用天然硅酸盐矿物材料高岭土对染料废水亚甲基蓝进行吸附去除研究,采用平衡吸附法研究不同高岭土投加量、溶液初始pH条件下高岭土对亚甲基蓝吸附去除的影响,进一步考察了热力学和动力学吸附规律,确定最佳的试验条件。结果表明:高岭土最佳投加量选择0.8 g/L,对亚甲基蓝的吸附量随初始pH的升高而增加;热力学研究表明,Koble-Corrigan模型对吸附过程的拟合度最高,更适合高岭土对亚甲基蓝的吸附行为,吸附过程是一个自发吸热的过程;动力学研究表明,在60min时基本达到吸附平衡,吸附过程符合准二级动力学的吸附模型。     

Fe3O4/δ-MnO2纳米片的制备及其对 亚甲基蓝的吸附研究

采用拓扑氧化法制备δ-二氧化锰六边形纳米片,通过共沉淀法控制pH=10,使Fe2+与Fe3+发生共沉淀形成四氧化三铁沉积于δ-二氧化锰纳米片表面,形成Fe3O4/δ-MnO2磁性六边形纳米片。研究了铁用量对Fe3O4/δ-MnO2结构和晶相的影响。利用X射线衍射（XRD）、场发射扫描电子显微镜（FESEM）等技术手段对其进行表征分析。研究了Fe3O4/δ-MnO2磁性纳米片对亚甲基蓝溶液的吸附行为,系统分析了吸附剂用量、亚甲基蓝初始浓度和吸附时间对吸附效率的影响。Fe3O4/δ-MnO2六边形纳米片尺寸大小均一,边长约为100 nm。该材料对亚甲基蓝表现出良好的吸附性能,当吸附时间为1 h时吸附量约为2.7 mg/g,去除率约为86.3%。     

Fe3O4@MOF-199@C18的制备及其对亚甲基蓝吸附的影响

采用水热法合成了Fe3O4@MOF-199@C18磁性纳米材料,并以此为吸附剂进行对亚甲基蓝的吸附实验,考察了Fe3O4@MOF-199@C18材料的吸附性能。通过红外光谱、扫描电镜、透射电镜等手段对该磁性材料进行了表征,结果表明此合成材料为质地均匀、表面多孔的磁性纳米材料。Fe3O4@MOF-199@C18磁性纳米材料吸附亚甲基蓝的最佳吸附条件为:pH为4,振荡时间为35 min,材料用量为5 mg,亚甲基蓝初始浓度为3 mg/L时,Fe3O4@MOF-199@C18磁性纳米材料对亚甲基蓝的吸附量为12.81 mg/g。重复利用实验结果表明,Fe3O4@MOF-199@C18材料至少可以重复利用7次。     

Removal of methylene blue dye from aqueous solutions by a new chitosan/zeolite composite from shrimp waste: Kinetic and equilibrium study

The adsorption of methylene blue dye (MBD) from aqueous solutions was investigated using a new composite made up of shrimp waste chitosan and zeolite as adsorbent. Response surface methodology (RSM) was used to optimize the effects of process variables, such as contact time, pH, adsorbent dose and initial MBD concentration on dye removal. The results showed that optimum conditions for removal of MBD were adsorbent dose of 2.5 g/L and pH of 9.0, and initial MBD concentration of 43.75 mg/L and contact time of 138.65 min. The initial concentration of dye had the greatest influence on MBD adsorption among other variables. The experimental data were well fitted by the pseudo-second order kinetic model, while the Freundlich isotherm model indicated a good ability for describing equilibrium data. According to this isotherm model, maximum adsorption capacity of the composite was 24.5 mg/g. Desorption studies showed that the desorption process is favored at low pH under acidic conditions.     

Fe3O4@SA/CTS凝胶球对亚甲基蓝及碱性品红的吸附

为解决染料对水体污染问题,本工作以海藻酸钠为骨架,结合Fe3O4及壳聚糖,制备了Fe3O4@SA/CTS凝胶球,并对制备的材料进行了微观表征。研究了不同影响因素下,吸附剂对MB及CB的吸附效果,同时研究了不同pH下对混合液的吸附性能,以及吸附剂循环利用性实验。结果表明,MB或CB初始浓度为100 mg/L、吸附剂投加量为1.0 g/L、MB的pH为11或CB的pH为8、反应时间4 h、MB和CB的去除率分别可以达到91.9%和21.5%。Langmuir模型能够更好反应对MB或CB的吸附,吸附以单分子物理吸附为主。吸附动力学符合伪二级动力学方程,吸附过程更容易受到化学吸附影响。不同pH下,Fe3O4@SA/CTS对混合液中的MB吸附优于CB,5次脱附循环使用后对MB保持在70%以上,对CB的去除率保持在15%以上。     

Synthesis of citric acid modified β-cyclodextrin/activated carbon hybrid composite and their adsorption properties toward methylene blue

In this article, citric acid modified β-cyclodextrin/activated carbon hybrid (CA-β-CD/AC) composites were synthesized by crosslinking reaction, and their adsorption properties for methylene blue were studied. The scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and Brunauer–Emmett–Teller (BET) method were used to characterize the structure and the morphology of composite materials. It was investigated that the effect of experiment parameters on the adsorption performance including weight fraction of AC in the composite, the adsorbent dose, the initial concentration of MB, the solution pH value, contact time, and temperature. The maximum adsorption capacity calculated by the Langmuir isotherm is 862.07 mg g⁻¹. Kinetic studies show that the adsorption process follows the pseudo-first-order and pseud-second-order reaction models. Thermodynamic analysis indicated that the adsorption behavior was an exothermic reaction. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48315.     

Least square-support vector (LS-SVM) method for modeling of methylene blue dye adsorption using copper oxide loaded on activated carbon: Kinetic and isotherm study

A multiple linear regression (MLR) model and least square support vector regression (LS-SVM) model with principal component analysis (PCA) was used for preprocessing to predict the efficiency of methylene blue adsorption onto copper oxide nanoparticle loaded on activated carbon (CuO-NP-AC) based on experimental data set achieved in batch study. The PCA-LSSVM model indicated higher predictive capability than linear method with coefficient of determination (R²) of 0.97 and 0.92 for the training and testing data set, respectively. Firstly, the novel nanoparticles including copper oxide as low cost, non-toxic, safe and reusable adsorbent was synthesized in our laboratory with a simple and routine procedure. Subsequently, this new material properties such as surface functional group, homogeneity and pore size distribution was identified by FT-IR, SEM and BET analysis. The methylene blue (MB) removal and adsorption onto the CuO-NP-AC was investigated and the influence of variables such as initial pH and MB concentration, contact time, amount of adsorbent and pH, and temperature was investigated. The results of examination of the time on experimental adsorption data and fitting the data to conventional kinetic model show the suitability of pseudo-second order and intraparticle diffusion model. Evaluation of the experimental equilibrium data by Langmuir, Tempkin, Freundlich and Dubinin Radushkevich (D-R) isotherm explore that Langmuir is superior to other model for fitting the experimental data in term of higher correlation coefficient and lower error analysis.     

常压下Fe3O4@C磁性复合材料的制备及其对亚甲基蓝的吸附

以共沉淀法合成的Fe₃O₄为载体,在常温常压下,利用浓硫酸蔗糖碳化法制备出Fe₃O₄@C磁性复合材料,通过傅里叶变换红外光谱仪（FTIR）、X射线粉末衍射仪（XRD）、扫描电镜（SEM）、透射电镜（TEM）和磁学测量系统（MPMS）手段对合成的磁性复合材料进行表征,并研究了Fe₃O₄@C对水中亚甲基蓝的吸附性能。考察了吸附剂用量、溶液pH、吸附温度、震荡时间等因素对吸附过程的影响。结果表明,Fe₃O₄@C表面分布有大量不规则的孔道,其饱和磁化强度为18.45emu/g;当亚甲基蓝初始浓度为100mg/L,吸附剂加入量1g/L,吸附时间150min,吸附温度25℃,pH=12时,得到吸附容量为96.74mg/g。Fe₃O₄@C对水中亚甲基蓝的吸附符合Langmuir模型,吸附过程动力学符合准二级动力学方程,吸附过程是吸热及熵增加的过程;Fe₃O₄@C经过稀硫酸溶液解吸之后可以重复利用。     

聚丙烯酸/聚丙烯酰胺/凹凸棒复合材料对亚甲基蓝的吸附性能

将聚(丙烯酸-co-丙烯酰胺)/凹凸棒复合吸附剂用于亚甲蓝的吸附,研究了时间、浓度、酸度、表面活性剂和离子强度等因素对吸附性能的影响。复合吸附剂对亚甲蓝的吸附是吸热过程,60℃时吸附量达到1 273.3 mg.g-1,吸附过程符合Langmuir单分子层吸附等温模式,并计算了热力学常数ΔG、ΔH和ΔS。在实验考察范围内吸附过程均符合准二级动力学特征。该复合吸附剂具有高吸附容量和较快的吸附速率,是良好的亚甲蓝吸附剂。     

H6P2W18O62/MIL-101(Fe)材料的制备及其吸附性能

采用溶剂热合成法在制备MIL-101(Fe)的过程中引入杂多酸H_6P_2W_(18)O_(62),制备出吸附剂H_6P_2W_(18)O_(62)/MIL-101(Fe),并测试了其对亚甲基蓝(MB)的吸附性能。考察了H_6P_2W_(18)O_(62)的负载量、MB质量浓度、溶液pH、温度等对材料的吸附性能。通过XRD、SEM、FTIR、N2吸附-脱附等手段对材料进行表征。结果表明:吸附平衡前,吸附量随MB质量浓度的增加而增加,在溶液pH=4、H_6P_2W_(18)O_(62)负载量相对于复合物质量分数为35%的条件下,吸附剂H_6P_2W_(18)O_(62)/MIL-101(Fe)对亚甲基蓝溶液吸附效果最佳,在303K下H_6P_2W_(18)O_(62)/MIL-101(Fe)对MB的最大吸附量可达148.1 mg/g。通过动力学和热力学分析,该吸附过程符合拟二级动力学与Langmuir等温吸附模型,同时是一个吸热、自发的过程。     

Preparation of hemicellulose‐g‐poly(methacrylic acid)/carbon nanotube composite hydrogel and adsorption properties

An organic–inorganic composite hydrogel was prepared based on hemicellulose and multi‐wall carbon nanotubes. The effects of hydrogel amount, initial concentration, contact time, and salt concentration on the adsorption performance of the prepared hydrogels were observed using methylene blue as a model hazardous material. The results indicated that the adsorption kinetic of methylene blue on the prepared adsorbent was well fitted to the pseudo‐second‐order kinetic model and the adsorption isotherm conformed to the Freundlich model. Removal percentage of methylene blue increased with increased adsorbent amount and kept higher than 98% when adsorbent amount was above 6 g L⁻¹. Adsorption amount of methylene blue on the prepared adsorbent also increased when increasing initial concentration over the range from 50 to 500 mg L⁻¹. Both of adsorption amount and removal percentage increased with an increase in the contact time, and removal efficiency obviously deteriorated as salt concentration increased. All obtained results reported that the prepared composite hydrogel would have an application prospect in water treatment. POLYM. COMPOS., 35:45–52, 2014. © 2013 Society of Plastics Engineers     

Equilibrium and kinetics of adsorption of methylene blue on Ti‐modified volcanic ashes

Volcanic ashes (VAs) and Ti‐modified volcanic ashes (TVA) were investigated as inexpensive adsorbents to remove methylene blue (MB) from aqueous solutions. TVA displayed higher and faster MB adsorption than VA. Adsorption studies were carried out in a batch system at room temperature. In this work, several variables were studied: contact time, pH, initial MB concentration, and adsorbent dosage. The equilibrium data of MB adsorption were analyzed according to the Langmuir and Freundlich adsorption isotherm models. Optimum adsorption performance for TVAs particles, prepared using a hydrothermal method, was obtained at pH = 10 and 3 g/l adsorbent dose. MB adsorption isotherm data can be described satisfactorily by the Langmuir equation, whereas adsorption kinetic data fit a pseudo second‐order kinetics model. © 2010 American Institute of Chemical Engineers AIChE J, 2011