阳离子木屑纤维素吸附剂的制备及其吸附性能研究

通过木屑纤维素的改性制备阳离子木屑纤维素吸附剂,研究其最佳制备条件及对1-萘酚的吸附条件,并对产物进行SEM表征。结果表明,最佳合成条件:CTA/MC质量比2:1,反应时间1.5 h,Na OH溶液浓度20.0%;最适宜的吸附条件为:在吸附剂用量2.5 g,p H 5.0,吸附时间2.0 h,处理25 m L 1-萘酚溶液(20 mg/L),吸附率可达89.56%。     

Co3O4对2,4-二氯苯酚的吸附性能影响

以硝酸钴(Co(NO₃)₂·6H₂O)为钴源,考察了不同沉淀剂(6 mol/L氨水、1 mol/L NaOH溶液、饱和碳酸铵溶液)对Co₃O₄吸附2,4-二氯苯酚(2,4-DCP)性能的影响。考察了焙烧温度、pH值、沉淀剂种类、吸附剂用量、2,4-DCP初始质量浓度对Co₃O₄吸附性能的影响,并进行了离子干扰实验。结果表明,焙烧温度为300℃、pH=9.0、沉淀剂为1 mol/L NaOH时,Co₃O₄对20 mg/L 2,4-DCP吸附性能最佳。Co₃O₄对2, 4-DCP的动力学吸附过程符合准二级动力学方程,等温吸附方程符合Langmuir方程,吸附过程以单分子层化学吸附为主。     

介孔Co-Cu-Ox吸附剂的制备及其吸附有机污染物的性能研究

以金属Co为基础,通过加入不同的金属合成双金属氧化物Co-M-Ox(M:Fe、Cu、Ni),用于水溶液中2,4-二氯苯酚(2,4-DCP)的吸附去除。结果表明:Co、Cu金属质量比为50%∶50%,以NaOH为沉淀剂调节至pH 9,300℃焙烧条件下制得的双金属氧化物对水溶液中2,4-DCP具有很好的吸附性;在25℃吸附条件下,吸附剂的最佳用量为0.2 g;并通过离子干扰实验、动力学以及等温吸附方程拟合得知金属离子的存在基本不影响吸附剂的吸附性能,吸附过程更符合准二级动力学方程及Freundlich等温吸附模型。     

醇水体系制备纳米Pd/Fe颗粒去除水中2,4-DCP

为了提高纳米铁的活性和分散性,在醇水体系下制备出纳米钯铁(Pd/Fe)双金属颗粒并表征,将制得的纳米Pd/Fe颗粒应用于水中2,4-二氯苯酚(2,4-DCP)的去除,考察了材料投加量、反应温度、初始pH值、2,4-二氯苯酚初始浓度等因素对2,4-DCP去除的影响,分析了2,4-DCP的去除机理并进行动力学拟合.结果表明...     

醇水体系制备纳米Pd/Fe颗粒去除水中2,4-DCP

为了提高纳米铁的活性和分散性,在醇水体系下制备出纳米钯铁(Pd/Fe)双金属颗粒并表征,将制得的纳米Pd/Fe颗粒应用于水中2,4-二氯苯酚(2,4-DCP)的去除,考察了材料投加量、反应温度、初始pH值、2,4-二氯苯酚初始浓度等因素对2,4-DCP去除的影响,分析了2,4-DCP的去除机理并进行动力学拟合。结果表明,在醇水体系中制备纳米铁有利于纳米颗粒的稳定分散;钯的加入将脱氯途径转变为催化加氢,极大改善了2,4-DCP的去除效果;当2,4-DCP初始浓度为20 mg/L、反应温度30℃、纳米Pd/Fe颗粒投加量为2 g/L时,2,4-DCP可在5 h内去除99.9%;反应过程符合修正的一级反应动力学方程。     

声光催化降解2,4-二氯苯酚研究(Ⅰ)反应条件的影响

研究了超声场强化在光催化高级氧化技术中的应用,以2,4-二氯苯酚(2,4-DCP)为典型污染物,考察了光催化剂TiO_2浓度、2,4-DCP初始浓度、超声功率和频率、溶液pH值,氯离子以及在反应体系中通入气体种类对降解过程的影响.在优化条件下,溶液中10.0 mg·L~(-1)的2,4-DCP可在30分钟内完全降解.在超声分散作用下,光催化剂浓度0.1 g·L~(-1)效果较好,光催化剂浓度过高反而不利于降解.在体系中通入含氧气体有利于2,4-DCP降解,而通入N_2不利于降解.在碱性条件下,2,4-DCP降解速率更快.溶液中氯离子会抑制2,4-DCP降解.结合光催化和功率超声理论,对实验结果进行了初步解释并探讨了超声强化光催化降解的作用机制.     

改性纳米铁镍去除水中2,4-DCP的研究

采用Pluronic F-127改性纳米零价铁后负载镍,形成改性纳米铁镍(F-NZVI/Ni)。探讨了Ni的负载量、F-NZVI/Ni的投加量、2,4-DCP初始浓度、pH及反应温度对2,4-DCP去除率的影响。同时探究了F-NZVI/Ni去除2,4-DCP的最佳条件下F-NZVI/Ni去除2,4-DCP的反应过程。结果表明,F-NZVI/Ni去除2,4-DCP的能力优于NZVI,当F-NZVI/Ni投加量为3 g/L,镍负载率为5%,2,4-DCP初始浓度为20 mg/L,反应温度为35℃,初始pH值为7时,2,4-DCP的去除率为97%。F-NZVI/Ni去除2,4-DCP主要是先吸附,然后在镍催化剂作用下将2,4-DCP降解为苯酚。     

改性纳米铁镍去除水中2,4-DCP的研究

采用Pluronic F-127改性纳米零价铁后负载镍,形成改性纳米铁镍(F-NZVI/Ni)。探讨了Ni的负载量、F-NZVI/Ni的投加量、2,4-DCP初始浓度、pH及反应温度对2,4-DCP去除率的影响。同时探究了F-NZVI/Ni去除2,4-DCP的最佳条件下F-NZVI/Ni去除2,4-DCP的反应过程。结果表明,F-NZVI/Ni去除2,4-DCP的能力优于NZVI,当F-NZVI/Ni投加量为3 g/L,镍负载率为5%,2,4-DCP初始浓度为20 mg/L,反应温度为35℃,初始pH值为7时,2,4-DCP的去除率为97%。F-NZVI/Ni去除2,4-DCP主要是先吸附,然后在镍催化剂作用下将2,4-DCP降解为苯酚。     

HDX-8树脂对2,4-二氯苯酚吸附的研究

研究了HDX-8树脂对2,4-二氯苯酚的吸附性能。结果表明,静态条件下在pH2~6范围内,对2,4-二氯苯酚具有良好的吸附性能,最大静态吸附量为9.725 mg 2,4-二氯苯酚/g树脂。等温吸附符合Freundlich和Langmuir方程式,相关系数均在0.99以上;柱长8 cm,内径1.0 cm,内装2.5 g HDX-8树脂的吸附柱对流速为5 mL/min,浓度为20μg/mL的2,4-二氯苯酚溶液的吸附率达到99%;负载柱可用1 mol/mL的NaOH洗脱。     

ZH-03树脂对苯酚和2,4-二氯苯酚的吸附机理研究

在静态条件下,研究了水溶液中新型树脂ZH-03吸附苯酚和2,4-二氯苯酚的热力学特性,测定了在288k、303k、318k和下降到288k温度下的吸附等温线。结果表明,在稀溶液中ZH-03吸附剂对苯酚和2,4-二氯苯酚的吸附同时符合Langm u ir和F reund lich模型。该树脂对苯酚的吸附是一个放热过程,而对2,4-二氯苯酚的吸附属于吸热过程,同时不同温度下的吸附等温线和热力学计算结果都证明了在树脂ZH-03对2,4-二氯苯酚吸附行为中存在着化学吸附。     

Adsorption of 2,4-dichlorophenol from Aqueous Solution by a New Low-Cost Adsorbent – Activated Bamboo Charcoal

Adsorption experiments were conducted to study the removal of 2,4-dichlorophenol (2,4-DCP) from aqueous solution by a new low-cost adsorbent-activated bamboo charcoal. The results showed that acidic pH was favorable for the adsorption and removal of 2,4-DCP. Higher initial 2,4-DCP concentrations led to higher adsorption capacity. Most of the adsorption of 2,4-DCP occurred within the first 5 min, and about 90% of 2,4-DCP were removed from solution. After 5 min, the adsorption capacity increased slowly with contact time and the adsorption reached equilibrium in less than 100 min. As the adsorbent dose was increased, the removal of 2,4-DCP was increased, while the equilibrium time was slightly affected. Adsorption kinetics could be best described by the pseudo-second-order model, independent of adsorbent dosages. The adsorption behavior of 2,4-DCP onto bamboo charcoal fitted both Langmuir and Freundlich isotherms well, but followed Freundlich isotherm more precisely. This study demonstrated for the first time that activated bamboo charcoal could be used for the removal of 2,4-DCP in water treatment.     

Adsorption of 2,4-dichlorophenol on metal-nitrate modified activated carbon

To remove 2,4-dichlorophenol (2,4-DCP) from aqueous solution, the surface of the activated carbon was first treated with HCl and then the surface was modified by using various metal ions (Cu, Co, Fe, Ni, Zn, and Mg). Metal doping significantly enhanced the adsorption efficiency of activated carbon, an effect that was further increased by HCl treatment of the modified activated carbons. Of all the preparations, the zinc(II)-modified activated carbon with HCl treatment showed the highest adsorption capacity for 2,4-DCP. Analysis of the zinc(II)-modified activated carbon by SEM and BET showed a surface area and micropore volume of around 1,154.69 m²/g and 0.291 cm³/g, respectively, values about 20% higher than in the starting material. In the pH range of 2.0–11.0, the maximum uptake of 2,4-DCP from an initial concentration of 1,000 mg/L was 508 mg/g at pH 4.0.     

Molecular Imprinted Polymer of Methacrylic Acid Functionalised β-Cyclodextrin for Selective Removal of 2,4-Dichlorophenol

This work describes methacrylic acid functionalized β-cyclodextrin (MAA-βCD) as a novel functional monomer in the preparation of molecular imprinted polymer (MIP MAA-βCD) for the selective removal of 2,4-dichlorophenol (2,4-DCP). The polymer was characterized using Fourier Transform Infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) and Field Emission Scanning Electron Microscopy (FESEM) techniques. The influence of parameters such as solution pH, contact time, temperature and initial concentrations towards removal of 2,4-DCP using MIP MAA-βCD have been evaluated. The imprinted material shows fast kinetics and the optimum pH for removal of 2,4-DCP is pH 7. Compared with the corresponding non-imprinted polymer (NIP MAA-βCD), the MIP MAA-βCD exhibited higher adsorption capacity and outstanding selectivity towards 2,4-DCP. Freundlich isotherm best fitted the adsorption equilibrium data of MIP MAA-βCD and the kinetics followed a pseudo-second-order model. The calculated thermodynamic parameters showed that adsorption of 2,4-DCP was spontaneous and exothermic under the examined conditions.     

环氧氯丙烷改性花生壳吸附水中Cu~(2+)的研究

利用环氧氯丙烷对花生壳改性制备吸附剂,并用其吸附水溶液中Cu2+。实验结果显示,花生壳的改性条件为:花生壳5.0 g,浓度为1.5 mol/L NaOH溶液100 mL,环氧氯丙烷5 mL,反应温度30℃,反应40 min;用上述条件改性花生壳0.3 g,吸附初始浓度50 mg/LCu2+溶液,控制溶液的pH为5.0,吸附时间3.0h,对Cu2+吸附率可达96.0%,高于未改性花生壳的70.4%,使吸附率提高36.4%。     

磁性聚合物微球在Cr(VI)吸附分离中的应用(英文)

The magnetic poly-(methacrylate-divinyl benzene) microspheres with micron size were synthesized by modified suspension polymerization method.Adsorption of Cr(VI) from aqueous solution by magnetic poly-(MA-DVB) microspheres with surface amination was investigated.The adsorption processes were carried out under diversified conditions of pH value,adsorption time and temperature to evaluate the performance of the mag-netic microspheres.The optimum pH value for Cr(VI) adsorption was found as 3.The adsorption capacity increased with adsorption time and attained an optimum at 60 min.The adsorption processes for magnetic microspheres was endothermic reaction,and the adsorption capacity increased with increasing temperature.     

双甘膦修饰磁性四氧化三铁纳米微球吸附DNA的研究

用双甘膦(PMIDA)修饰磁性四氧化三铁纳米微球(MNP)并负载Zn2+制得了PMIDA-Zn2+修饰磁性微球吸附剂。考察了吸附溶液的pH值、离子强度、吸附时间、吸附温度等因素对DNA吸附的影响。结果表明,当吸附剂用量为10mg、pH值为5.0、离子强度(NaCl浓度)为2.0mol.L-1、吸附时间为20min、吸附温度为35℃时,吸附率可达80%,吸附容量为21mg.g-1。被吸附的DNA用3.5%的氨水能完全洗脱。将PMIDA-Zn2+修饰磁性微球用于玉米DNA的提取,所得DNA纯度较高,效果令人满意。     

壳聚糖对Pb(Ⅱ)的吸附及动力学研究

研究了壳聚糖（CTS）微粒吸附Pb（Ⅱ）时pH值、温度、溶液浓度对吸附量的影响及壳聚糖微粒对Pb（Ⅱ）的吸附动力学特性,结果表明其吸附最适pH值为5,在30-60℃范围内,随吸附温度的升高,吸附量增大。壳聚糖与Pb（Ⅱ）之间发生反应,其吸附行为可用Freundlich单分子层吸附机理解释,且Lagergren二级方程与吸附研究吻合较好。     

丝瓜瓤固定黄孢原毛平革菌对2,4-二氯酚的降解研究

利用植物载体丝瓜瓤对黄孢原毛平革菌进行固定,研究了固定化细胞对2,4-二氯酚的降解性能。利用固定化细胞流化床反应器连续处理质量浓度为20mg/L的2,4-二氯酚废水。考察了不同水力停留时间对处理效果的影响。结果表明,采用吸附生长法能有效实现黄孢原毛平革菌的固定,固定细胞量可达0.791g[细胞]/[丝瓜瓤]。固定化细胞最适降解温度和pH值分别为35℃、6.0。对于质量浓度在20mg/L以下的低浓度2,4-二氯酚,固定化细胞和游离细胞的降解速率相当;对于质量浓度在50～120mg/L的高浓度2,4-二氯酚,固定化细胞具有明显优势,不仅可以耐受更高浓度的2,4-二氯酚,其降解速率也高于游离细胞,最大降解速率是13.95mg/(L·d),是游离细胞的2倍。不同的水力停留时间对固定化细胞流化床反应器连续处理2,4-二氯酚的降解效率有很大影响,固定化细胞对2,4-二氯酚降解过程遵循Monod方程。     

两性壳聚糖的制备及其处理磷化废水的研究

以壳聚糖、3-氯-2-羟丙基三甲基氯化铵、氯乙酸为原料,制备了两性壳聚糖。以两性壳聚糖为吸附剂,处理磷化废水。通过单因素实验考察了pH、吸附剂用量、吸附时间和温度等因素对吸附效果的影响,对吸附机理进行了初探。结果表明,室温下最佳吸附工艺条件pH为2.0,ρ(吸附剂)为12.0g/L,吸附t为2.0h。此条件下,两性壳聚糖对磷化废水中锌离子和磷酸根的去除率分别达到78.9%和88.2%。