Kinetics of zirconium ions adsorption on activated charcoal from aqueous solutions

The batch kinetics of adsorption of the zirconium ions from aqueous solutions on activated charcoal has been investigated over a wide range of concentration of zirconium ions (1.0–5.0 g/l) and temperatures (10–50°C). The adsorption process of zirconium ions proceeds via two stages; the first stage is rather fast, followed by a much slower one. The Bangham equation was used to study the kinetics of the zirconium ions' adsorption on activated charcoal. It is observed that the diffusion of zirconium ions into the pores of the activated charcoal controls the kinetics of the adsorption process. Moreover, zirconium ion adsorption obeys the Freundlich and Langmuir isotherms in the concentration range studied. The adsorption equilibrium constant (k_c) values for zirconium ions adsorption on activated charcoal have also been calculated at different temperatures. Various thermodynamic quantities, ΔG, ΔH, and ΔS were computed from k_c values. The results showed that the adsorption of zirconium ions on activated charcoal is an endothermic process.     

高活性木炭的制备与孔结构表征

介绍了二步炭化法制备高活性木炭工艺。研究了保温时间和温度对活性木炭吸附性能的影响,并通过ESEM和HRTEM等对其孔结构进行表征。结果表明:二步炭化法可很好地提高木炭的性能,可制得孔径主要集中在0.6～2.0nm的活性木炭;随着保温时间延长,活性木炭的比表面积、孔容积均增大。在较佳实验条件下,所制高活性木炭的比表面积、总孔容积和微孔容积分别为1288.4m2/g、0.784mL/g、0.407mL/g。     

聚偏氟乙烯膜亲水改性及其乳液分离与重金属吸附应用

聚偏氟乙烯（PVDF）膜因其优异的化学和力学稳定性而被广泛应用于水处理领域,但PVDF膜本身的疏水性,容易使其在处理含油废水的过程中被油滴污染,造成膜孔堵塞。以PVDF微滤膜为基底,通过单宁酸（TA）和聚乙烯亚胺（PEI）共沉积形成了TA/PEI黏附层,经戊二醛共价交联和接枝半胱氨酸（Cys）,制备了一种PVDF改性膜（PVDF@TA/PEI-Cys）。改性后的PVDF膜具有良好的亲水性和水下超疏油性,水接触角和水下油接触角分别为22.2°和150.2°。在0.09 MPa下,PVDF@TA/PEI-Cys膜的纯水通量达6328 L/（m²·h）,水包油型乳液分离效率高达99.9%。此外,该改性膜还可同时吸附水中的汞离子,最大吸附量为24.7 mg/g。     

Surface molecularly imprinted polymers based on yeast prepared by atom transfer radical emulsion polymerization for selective recognition of ciprofloxacin from aqueous medium

To achieve selective recognition of water‐soluble ciprofloxacin (CIP), an effective method was developed for the preparation of surface molecularly imprinted polymers based on the yeast particles (yeast@MIPs) via atom transfer radical emulsion polymerization (ATREP). The reactions were carried out in the nontoxic and green emulsion system at room temperature, which was environment friendly with low energy consumption. In this study, the yeast, for the advantages of low cost, easily available source and abundant active groups on the cell wall, was selected as an ideal biological support substrate. The prepared yeast@MIPs was characterized by FT‐IR, SEM, TEM, EDS, and elemental analysis techniques. Batch mode adsorption studies were carried out to investigate the specific adsorption equilibrium, kinetics, selective recognition, and reuse ability of yeast@MIPs. The experimental static adsorption data of CIP on to yeast@MIPs were well‐described by Langmuir, Freundlich, and pseudo‐second‐order models. The maximum static adsorption capacity for CIP of yeast@MIPs was 18.48 mg g^?1, and the adsorption equilibrium could be reached in 60 min. The selectivity coefficients for CIP relative to enrofloxacin, tetracycline, and sulfadiazine were 1.212, 2.002, and 10.65, which demonstrated CIP of high affinity and selectivity over three competitive antibiotics. In addition, the reusability of the material without obvious deterioration (8.52% loss) in performance was observed at least four repeated cycles. And the yeast@MIPs was used to determine CIP from spiked shrimp samples by HPLC analysis. These results showed that yeast was a well‐defined substrate and ATREP was a promising technique for the preparation of surface molecularly imprinted polymers targeting templates. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40310.     

炭纤维基复合吸附材料的制备及其气体分离性能研究

活性炭纤维基复合炭分子筛材料作为一种新型的吸附材料,具有丰富而发达的微孔结构、大的比表面积和优异的导电性能,这些性质使其具有独特的气体分离性能。本文以沥青基活性炭纤维和酚醛树脂为原料制备复合炭分子筛材料,用扫描电镜和氮吸附等温线法研究其外观型态和孔隙结构,在变电吸附工艺条件下以CO2为探针考察了此类复合吸附材料的分离性能。     

Recycling of waste attapulgite to prepare ceramic membranes for efficient oil-in-water emulsion separation

Large-scale application of ceramic membranes is restricted by high cost resulting from raw materials and sintering process. In this study, low-cost ceramic membranes were prepared with waste attapulgite (WAT) and α-Al₂O₃ as starting materials and used for oily wastewater treatment. The optimal membrane sintered at 1100 °C possessed excellent properties, with open porosity of 41.6%, flexural strength of 37.2 MPa and average pore size of 0.40 μm. The membrane also displayed outstanding permeability and chemical stability. The hydrophilicity and underwater oleophobicity were enhanced after surface modification. When used for oil-in-water emulsion filtration, the permeate flux reached 236.8 L m^?2 h^?2 bar^-1 under a low transmembrane pressure of 0.2 bar and the oil rejection exceeded 99%. Membrane cleaning with a simple ultrasonic treatment could easily achieve flux recovery. This study proposed a feasible strategy for both solid waste utilization and oily wastewater treatment.     

Co-MOF-74的合成及其吸附正己烷/1-己烯性能

采用溶剂热方法合成了Co-MOF-74,采用X射线衍射（XRD）、氮气吸附、红外光谱（FTIR）、热重-差热分析（TG-DSC）和扫描电子显微镜（SEM）对其进行表征,研究其吸附正己烷/1-己烯性能。结果表明,优化的Co-MOF-74合成工艺条件为：原料配比n[Co（NO₃）₂·6H₂O]：n（DHTP）：n（THF）：n（H₂O）=2：1：165：750,晶化温度100℃,晶化时间24h,150℃活化2h。合成Co-MOF-74对1-己烯和正己烷的静态饱和吸附量分别为125.6mg/g和72.9mg/g,BET比表面积为1209m²/g,孔体积为0.41cm³/g,微孔平均孔径为0.66nm。L-F吸附模型能较好地解释Co-MOF-74材料对1-己烯的吸附等温线数据,Co-MOF-74吸附1-己烯的过程是热力学自发放热过程。     

Effect of activated charcoal treatment of alkaline hydrolysates from sugarcane bagasse on purification of p-coumaric acid

The brown compounds in the ultrafiltration permeates resulting from the alkaline-hydrolysis of sugarcane bagasse were determined to be composed mainly of lignin monomers. These monomers significantly influence the separation and purification of p-coumaric acid. Addition of 3% of activated charcoal removed 78.10% of the compounds’ color value but adsorbed only 14.36% of the available coumaric acid in alkaline conditions. Decoloration by the application of activated charcoal before purification by anion exchange chromatography ensured the repeated use of the resins and crystallization of p-coumaric acid, thus significantly reducing preparation costs. A total of 8.56 g of crystal contained 95.2% of coumaric acid was obtained from 1 kg of sugarcane bagasse after decoloration and separation.     

乳状液膜分离技术的发展与应用

乳状液膜分离技术综合了固体膜分离法和溶剂萃取法的特点,是一种新兴的节能型分离手段。介绍了乳状液膜的组成和分类,并对其传质机理和分离过程中的影响因素进行了分析。对乳状液膜在废水处理和冶金工业方面的应用进行了具体介绍。     

以纸巾为模板制备活性炭纤维

以纸巾为前驱体通过NaOH化学活化制备活性炭纤维,扫描电镜观测其微观结构为多孔纤维状。通过活性炭纤维对亚甲基蓝的吸附实验研究活性炭纤维吸附动力学,Pseudo-second-order方程比Pseudo-first-order方程更适于吸附数据模型,相关系数高达0.998,所制备活性炭纤维对亚甲基蓝最大平衡吸附量为200mg/g。     

乳化剂对动态膜分离油水乳化液过程的影响

利用管状陶瓷膜基氧化锆动态膜分离油水乳化液，研究了4种工业常见乳化剂[斯盘80（SP-80）、十二烷基磺酸钠（SDS）、十二烷基硫酸钠（SLS）和十二烷基苯磺酸钠（SDBS）]对分离过程的影响。利用正交实验方法考察了乳化剂种类和浓度、乳化液温度和流量以及操作压力对过程的影响。正交实验结果表明，在SDS、1.0 g/L、50℃、120L/h和0.14MPa操作条件下，油水混合物稳定渗透通量最大。单因素实验结果表明，当乳化剂浓度增大时，稳定渗透通量减小；当乳化液温度升高时，稳定渗透通量先增加后降低。无机盐离子Na⁺、Ca²⁺和Al³⁺的存在均可使稳定渗透通量增加。当Al³⁺大于0.75g/L时，乳化液的稳定性被完全破坏，更有利于提高渗透通量。基于实验结果，采用分子模拟方法研究了不同实验条件下乳化剂的乳化效果，分析了SDS的油水界面形成能（E）和水的界面扩散系数（D）与乳化剂浓度和乳化液温度的关系。模拟结果表明，E和D绝对值均随着乳化剂浓度和乳化液温度增加而增大。实验和模拟结果均表明，乳化剂的乳化效果决定了油滴的平均粒径，基于油水分离的堵塞机理，也由此影响了稳定渗透通量。模拟结果从微观角度解释了实验现象，研究结果可为动态膜处理油水乳化液的工业应用提供依据。     

种子乳液聚合制备MCPU-PMMA复合乳液

本文采用改性蓖麻油合成了软段中含不饱和双键的阴离子聚氨酯水分散液（MCPU），将其作为可聚合乳化剂和种子成分同甲基丙烯酸甲酯（MMA）进行共聚，制得了MCPU－PMMA复合乳液。1HNMR谱图显示MCPU中含有双键结构,共聚后双键消失。通过考察单体转化率和复合乳液平均粒径、凝胶量及成膜耐水及甲苯性探讨了影响种子乳液聚合的多种因素：采用过硫酸钾作为引发剂，单体转化率高，乳液粒径小，成膜耐水及甲苯性好；反应的表观活化能Ea为164.86kJ/mol，反应温度控制在70℃较适宜；聚合反应速率Rp∝［I］1.0856，引发剂用量宜控制在聚合有效组份总质量的0.5％。     

Preparation and application of supported demulsifier PPA@SiO2 for oil removal of oil-in-water emulsion

ABSTRACT

To improve the separation efficiency of oil-in-water emulsion of produced water from ASP (Alkaline/Surfactant/Polymer) flooding, a modified silica gel-supported polyether polyquaternium (PPA@SiO₂) was developed as a demulsifier for separating oil-in-water emulsion. The performance of oil removal using PPA@SiO₂ is achieved under combined demulsification and adsorption, the polyether polyquaternium (PPA) was functionalized by displacement and charge neutralization as demulsifier, the modified silica gel (MPS-SiO₂) was functionalized by adsorbing oil droplets as adsorbent. PPA@SiO₂ was synthesized and characterized using FTIR, XPS, SEM, and N₂ sorption analysis. PPA@SiO₂ was applied for the treatment of oil-in-water emulsion of produced water from ASP flooding. A 92.31% of oil removal is obtained under conditions as following: a 500 mg/L of initial oil concentration, a 1.5 g of PPA@SiO₂, a 30°C of demulsifying temperature and a 60 min of demulsifying time. MPS-SiO₂ particles after demulsifying exhibited a high adsorption capacity of 303.6 mg/g. This work not only provides a promising demulsification to demulsify the oil-in-water emulsion of produced water from ASP flooding but also gives a demulsify method combined demulsify and adsorb.     

醋丙乳液HG-498的合成及性能

采用半连续种子乳液聚合方法,合成了一种高性能醋酸乙烯-丙烯酸丁酯-新癸酸乙烯酯三元共聚乳液(简称醋丙乳液)。探讨了乳化剂的配比、单体的用量、聚合温度、引发剂的用量和单体滴定时间对产品性能的影响。确定了聚合配方,优化了聚合工艺。实验结果表明,丙烯酸丁酯为单体总量的25%、阴离子型与非离子型乳化剂的质量比为1∶1、聚合温度为80℃、单体滴定时间为1.5~2 h时,乳液综合性能良好。同时对胶体稳定性进行了相关表征:乳液外观为乳白色且泛蓝光,胶体冷冻24 h后,无破乳现象发生,无悬浮颗粒,pH值6.4,固含量49.7%,黏度116 Pa s,黏均分子质量为36 872左右。·     

Modeling the selectivity of activated carbons for efficient separation of hydrogen and carbon dioxide

Grand canonical Monte Carlo simulations (GCMC) are carried out to investigate the separation of hydrogen and carbon dioxide via adsorption in activated carbons. In the simulations, both hydrogen and carbon dioxide molecules are modeled as Lennard-Jones spheres, and the activated carbons are represented by a slit-pore model. At elevated temperatures (T = 505 and 923 K), the activated carbons exhibit essentially no preference over the two gases and the selectivity of carbon dioxide relative to hydrogen falls monotonically as the pore size increases. At room temperature, however, the selectivity of carbon dioxide relative to hydrogen reaches up to 90, indicating that hydrogen and carbon dioxide can be efficiently separated. Furthermore, the optimized pore sizes, of width H = 1.48 nm for the bulk mole fraction ratio of x_CO2/x_H2=1:2 and H = 1.18 nm for x_CO2/x_H2=1:8, are identified in which the activated carbons show the highest selectivity for the separation of hydrogen and carbon dioxide.     

丙烯酸酯-富马酸酯共聚乳液的合成及表征

采用半连续乳液聚合方法,以甲基丙烯酸甲酯（MMA）、富马酸二丁酯（DBF）为主单体,丙烯酸（AA）为功能单体,十二烷基硫酸钠（SDS）为乳化剂,过硫酸钾（KPS）为引发剂,合成了固含量为30%的共聚物乳液。探讨了单体配比、SDS用量、KPS用量对乳液及胶膜性能的影响。结果表明,乳胶粒子有核壳结构,当DBF/MMA比例为1/1.5,SDS为单体总质量的3%,KPS为0.4%时,乳液涂料综合性能达到最佳,涂膜光泽度、附着力良好,力学性能及耐化学试剂性能优良。     

催化裂化干气分离丙烯用活性炭吸附剂的特性研究

为了获得可用于催化裂化干气中吸附分离丙烯用的活性炭,选择国内有代表性的不同材质和产地的活性炭,测定了比表面积、孔容、平均孔径和微孔体积等物性参数.在自制的吸附实验装置上,测定了101.3 kPa、40℃下丙烯和乙烯在不同活性炭上的吸附量,比较对丙烯的选择性.结果表明在上述吸附条件下,活性炭AC-1对丙烯的吸附量最大,达3.552 mmol/g,对丙烯的选掸性为1.37.测定了乙烯丙烯二元混合气中,不同丙烯分压下,活性炭AC-1对丙烯和乙烯的吸附量.活性炭AC-1适用于干气吸附分离丙烯过程.     

Synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

Many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue (black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir's equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, EA, SEM, Nitrogen adsorption (specific surface areas of 879 and 652 m²·g^-1), and their points of zero charge (2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed (58-59.8 mg·g^-1) in greater amounts compared to anionic dyes (10-58.8 mg·g^-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.     

水性丙烯酸酯乳液的合成及性能研究

以双丙酮丙烯酰胺（DAAM）为功能性单体,采用预乳化半连续种子乳液聚合法合成水性丙烯酸酯乳液,添加己二酸二酰肼（ADH）为交联剂,构成室温自交联体系。考察了DAAM、ADH用量对乳液及其乳胶膜性能的影响。用傅里叶红外光谱仪（FT-IR）对交联反应进行了表征。通过差示扫描量热法、力学性能和耐溶剂性能的测试等方法研究了乳液和乳胶膜的性能。结果表明,当DAAM用量为2.4%~3.5%,ADH与DAAM的当量比为1~1.2时,乳液和乳胶膜的综合性能较好。     

核-壳结构含氟丙烯酸酯乳液的合成与表征

A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate （MMA） and butyl acrylate （BA） were used as main monomers and hexafluorobutyl methacrylate （HFMA） as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum （FT-IR）, transmission electron microscopy （TEM）, particle size analysis, X-ray photoelectron spectroscopy （XPS）, contact angle （CA）, differential scanning calorimetry （DSC） and thermogravimetry （TG） analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion.