固井用遇油自修复材料的研制与性能评价

采用悬浮聚合法,以甲基丙烯酸十二烷基酯(LMA)、苯乙烯(St)、甲基丙烯酸羟乙酯(HEMA)为聚合单体,过氧化苯甲酰(BPO)为引发剂,聚乙烯醇(PVA)为分散剂,二乙烯基苯(DVB)为交联剂,合成了一种树脂并应用到固井水泥石中。通过正交实验考察了单体、分散剂、引发剂、交联剂、温度对三元共聚树脂吸油性能的影响。结果表明:当m(LMA)∶m(St)∶m(HEMA)=6∶3∶1、w(PVA)=2.5%(以单体的总质量为基准,下同)、w(BPO)=1.0%、w(DVB)=0.5%、t=85℃时,三元共聚树脂的吸油性能最佳,二甲苯的吸油率达12.78 g/g。通过人工造缝,对加入树脂水泥石的渗透率和抗压强度进行了考察,结果表明:在25℃下,养护30 d后,水泥石渗透率随树脂的增加而降低,在w(树脂)=8.0%(以水泥质量为基准,下同)时低至2.50×10~(-4)μm~2,而抗压强度随树脂的增加先增加后减小,在w(树脂)=2.0%时达到最大值20.8 MPa,抗压强度恢复率达70.5%。     

固井用遇油自修复材料的研制与性能评价

采用悬浮聚合法,以甲基丙烯酸十二酯(LMA)、苯乙烯（St）、甲基丙烯酸羟乙酯（HEMA）为聚合单体,过氧化苯甲酰（BPO）为引发剂,聚乙烯醇(PVA)为分散剂,二乙烯基苯（DVB）为交联剂,合成了一种树脂并应用到固井水泥石中。通过正交实验考察了单体、分散剂、引发剂、交联剂、温度对三元共聚树脂吸油性能的影响。结果发现,当m(LMA):m(St):m(HEMA)=6:3:1、w(PVA)=2.5%、w(BPO)=1.0%、w(DVB)=0.5%、T=85℃时吸油性能最佳,二甲苯的吸油率达12.78 g/g。通过人工造缝,讨论了加入树脂的水泥石渗透率和抗压强度的变化规律,结果表明：养护30 d后,渗透率随树脂的增加而降低,在加量8.0%时低至0.25×10-3 μm2,而抗压强度随树脂的增加先增加后减小,在加量2.0%时达到最大值20.8 MPa,抗压强度恢复率达70.5%。     

新型硼螯合树脂的合成及其对盐湖卤水中硼的吸附

用甲基葡萄糖胺(MG)将甲基丙烯酸缩水甘油酯(GMA)和三甲基丙烯酸三甲醇基丙烷酯(TRIM)的大孔共聚物功能化改性,制备出新型硼特效螯合树脂. 通过红外光谱鉴定了大孔共聚物、螯合树脂及吸附硼后树脂的结构,研究了该树脂对盐湖卤水中硼的吸附性能,考察了树脂基体聚合物性质对硼吸附量的影响,并建立了树脂对硼的吸附动力学模型. 结果表明,聚合物单体中GMA含量对硼吸附量的影响较大,此类树脂吸附硼具有选择性高、吸附容量高、吸附速度快、易于脱附的优点,吸附动力学模型符合颗粒扩散模型.     

基于废轮胎胶粉的吸油树脂的制备与性能研究

采用悬浮聚合法以废轮胎胶粉和叔丁基苯乙烯(tBS)为单体、二乙烯苯(DVB)为交联剂、过氧化苯甲酰(BPO)为引发剂制备吸油树脂,并考察其吸油性能的影响因素.结果表明,tBS可以接枝到废轮胎胶粉分子链上;当废轮胎胶粉/tBS并用比为60/40、交联剂DVB用量为1份、引发剂BPO用量为1份时,吸油树脂的吸油率达到最大;随交联剂DVB用量的增大,吸油树脂的凝胶含量增大,吸油率则先增大后减小;吸油树脂在甲苯和原油/甲苯混合物中的吸油过程基本上遵循一级动力学方程.     

高铝粉煤灰碱法提铝过程镓的吸附研究

我国内蒙古中西部以及山西北部地区的高铝粉煤灰中氧化铝含量高达50%以上,伴生的镓含量可达60 mg/kg,是重要的含铝、镓二次资源。为进一步提升高铝粉煤灰资源化利用附加值,实现粉煤灰提铝过程低浓度含镓溶液的高效提取,本文基于高铝粉煤灰预脱硅拜耳-亚熔盐联合法提铝工艺中的含镓碱液体系,研究了含镓模型溶液中镓离子的静态吸附规律,系统考察了不同吸附时间、吸附温度、镓初始浓度以及碱浓度对螯合树脂吸附镓离子的影响,完成了吸附动力学与吸附等温线的考察,并采用吸附柱进行了低浓度含镓碱液动态吸附及淋洗试验验证。静态吸附试验结果表明:采用LSC-600型螯合吸附树脂可实现低浓度含镓碱液中镓离子的高效吸附,树脂的平衡吸附容量随静态吸附时间增大而增大,吸附24 h后树脂吸附容量达到平衡;镓离子初始浓度低于400 mg/L,树脂的平衡吸附容量受吸附温度影响较小,在镓离子浓度高于400 mg/L体系中,树脂的平衡吸附容量随吸附温度升高而降低,其中吸附温度为50℃时树脂对镓离子的平衡吸附容量最大;随含镓碱液碱浓度增加,螯合树脂对镓离子的吸附容量先增大后减小,螯合树脂对镓离子的平衡吸附容量随镓离子初始浓度增大而增大,镓离子初始浓度高于1 200 mg/L时树脂吸附容量达到饱和,吸附温度为50℃,镓离子初始浓度为1 200 mg/L,碱浓度为5 mol/L时树脂的最大吸附容量为36 mg/g。动力学拟合结果表明:碱体系树脂对镓离子的吸附动力学过程符合准二级动力学方程,属于化学吸附过程;吸附等温线拟合结果表明,LSC-600型螯合树脂对镓离子的吸附满足Langmuir等温方程,说明镓离子的螯合吸附过程为单层吸附。树脂的动态吸附和淋洗结果表明,液体流速越大,树脂达到吸附平衡时的穿透床层数越小,树脂对镓离子的吸附容量和吸附率均较低,镓离子初始浓度50 mg/L,吸附温度为50℃,吸附流速为2. 5 BV/h时,树脂对低浓度含镓碱液吸附效果最优,最大吸附容量为3. 13 mg/g,淋洗过程淋洗液镓离子浓度随着床层数增加先增大后降低,淋洗流出液达到0. 7 BV时镓浓度最高为1 936mg/L,高浓度段(0. 3～1. 5 BV)溶液中镓离子浓度为1 248 mg/L,富集倍数达25倍。     

丙烯酸酯二元高吸油树脂的合成及性能研究

以聚乙烯醇(PVA)为分散剂、二乙烯基苯(DVB)为交联剂、过氧化苯甲酰(BPO)为引发剂、乙酸乙酯(EA)为致孔剂,选用长链单体甲基丙烯酸十八烷基酯(SMA)和短链单体甲基丙烯酸异丁酯为原料以悬浮聚合法成功合成了一种丙烯酸酯二元共聚高吸油树脂。通过红外(FT-IR)、扫描电子显微镜(SEM)和热重(TG)分析法对树脂进行表征,并考察了各因素对4种待测油品吸油性能的影响。结果表明,该树脂对三氯甲烷、甲苯、环己烷、柴油的饱和吸油率分别为20.69、13.87、12.05、10.93 g/g。树脂的最佳合成条件为：w(SMA) 80%、w(BPO) 1%、w(DVB) 0.5%、w(PVA) 1%、w(EA) 50%、W/O为5∶1。     

单宁基酚胺型螯合树脂的制备及对Cr(Ⅵ)的吸附

杨梅单宁先与氯化亚砜反应制得氯代单宁,再与聚乙烯亚胺交联合成单宁基酚胺型螯合树脂.通过FTIR、SEM、EDS和XPS对单宁基酚胺型螯合树脂的结构进行表征,并考察了螯合树脂对Cr(Ⅵ)的吸附性能.在单宁的分子结构侧链引入氨基,能有效改善单宁基螯合树脂对Cr(Ⅵ)的吸附性能,螯合树脂对Cr(Ⅵ)的吸附主要为还原吸附,铬主要以Cr(Ⅲ)的形式吸附到树脂上;在温度为318 K、pH为2.0、Cr(Ⅵ)初始质量浓度为500 mg/L,吸附时间420 min时,单宁基酚胺型螯合树脂对Cr(Ⅵ)的最大吸附量达到364.46 mg/g;当Cr(Ⅵ)初始质量浓度低于20 mg/L时,单宁基酚胺型树脂对铬的吸附率达到95％以上;单宁基酚胺型螯合树脂对Cr(Ⅵ)的吸附过程符合Langmuir等温吸附模型和准二级吸附动力学方程.该树脂在含铬废水处理方面具有潜在的应用前景.     

多元共聚高吸油树脂的合成研究

以甲基丙烯酸十八酯(SMA)、丙烯酸丁酯(BA)和苯乙烯(St)为单体,二乙烯苯(DVB)为交联剂,过氧化苯甲酰(BPO)作引发剂,采用悬浮聚合法合成了高吸油性树脂,研究了体系中单体组成及配比、交联剂、分散剂及致孔剂用量等因素对吸油树脂性能的影响。结果表明:m(SMA):m(BA):m(St)=33:67:12,w(DVB)=1%,w(PVA)=1.2%,w(CHCl3)=35%时,所合成的树脂吸油性能最佳,其对柴油、甲苯、四氯化碳的饱和吸油倍率分别可达11.2g/g、18.9g/g、27.4g/g。     

新型偕胺肟基螯合树脂对Ni(Ⅱ)和Cu(Ⅱ)吸附性能研究

用表面引发原子转移自由基聚合(SI-ATRP)将丙烯腈(AN)接枝到氯甲基化聚苯乙烯树脂(PS-CH2Cl)表面,再由羟胺和腈基的胺肟转换反应得到偕胺肟基螯合树脂(PAO-g-PS)。采用红外和扫描电镜对树脂进行了表征,并研究了树脂对Ni(Ⅱ)和Cu(Ⅱ)的吸附性能。结果表明,树脂对Ni(Ⅱ)和Cu(Ⅱ)吸附容量分别达到1.58、1.01mmol/g,经过10次吸附-解吸循环试验,树脂的吸附容量无显著变化,表明树脂具有优异的吸附性能以及良好的重复使用性。     

单宁基酚胺型螯合树脂的制备及对Cr(VI)的吸附

杨梅单宁先与氯化亚砜反应制得氯代单宁,再与聚乙烯亚胺交联合成单宁基酚胺型螯合树脂。通过FTIR、SEM、EDS和XPS对单宁基酚胺型螯合树脂的结构进行表征,并考察了螯合树脂对Cr(VI)的吸附性能。在单宁的分子结构侧链引入氨基,能有效改善单宁基螯合树脂对Cr(VI)的吸附性能,螯合树脂对Cr(VI)的吸附主要为还原吸附,铬主要以Cr(III)的形式吸附到树脂上;在温度为318 K、pH为2.0、Cr(VI)初始质量浓度为500 mg/L时,单宁基酚胺型螯合树脂对Cr(VI)的最大吸附量达到364.46 mg/g;当Cr(VI)初始质量浓度低于20 mg/L时,树脂对铬的吸附率达到95%以上;单宁基酚胺型螯合树脂对Cr(VI)的吸附过程符合Langmuir等温吸附模型和准二级吸附动力学方程。该树脂在含铬废水处理方面具有潜在的应用前景。     

Gallium recovery from Bayer's liquor using hydroxamic acid resin

Gallium, which is extensively used in the production of semiconductor materials, is present at the parts per million level in Bayer's liquor. The low concentration of gallium in the liquor, along with the high concentration of aluminum, prompted the use of chelating ion exchangers as an alternative separation process. A chelating ion exchange resin with hydroxamic groups attached to the copolymer of acrylonitrile‐divinylbenzene has been prepared by suspension polymerization followed by hydrolysis and chelation with hydroxylamine hydrochloride. Adsorption studies of gallium, using the above hydroxamic acid resin, were carried out. Adsorption was dependent on particle size of the resin and optimum conditions are determined for obtaining 0.3‐ to 0.5‐mm particles by varying the composition of the emulsion, using a secondary polymerization technique, and adding of diluents. Acrylic acid, as a diluent in the copolymer matrix, was found to increase the particle size and stability of the resin. IR studies, carried out for the products obtained at various stages, confirmed the conversion of polymer to resin with a hydroxamic acid group and its complex formation with gallium. Both batch and column studies were carried out for the determination of the capacity of the resin with synthetic Bayer's liquor containing gallium and commercial Bayer's liquor. Scaled‐up column studies were carried out with commercial Bayer's liquor to test the cyclability and stability of the resin. It was observed that chelated ion exchange resin could be recycled up to 30 times. The optimal liquid to solid phase ratio was found to be 1:12. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 847–855, 2004     

Cross-linked polyvinyl amidoxime fiber: a highly selective and recyclable adsorbent of gallium from Bayer liquor

Gallium, a scarce metal produced mainly from Bayer liquor, is widely used in semiconductors. Ion-exchange method is currently considered as the most effective method to recover gallium from Bayer liquor. In this article, fibrous amidoxime adsorbents are introduced to recover gallium from Bayer liquor. In addition, hydrazine cross-linked polyvinyl amidoxime (HPAO) fibers have been prepared. The structure of the as-prepared fibers was ascertained by FTIR, elemental analysis and weight gain rate. The adsorption kinetics, adsorption isotherm and recycling performance were investigated by batch method. Cross-linking duration was studied and it turned out to be an important factor to optimize the adsorption capacity and recycling performance. After 1.5 h cross-linking time, the fiber showed the highest gallium adsorption capacity of 14.83 mg/g in Bayer liquor. After 3 h cross-linking time, the fiber showed the best recycling performance, which retained 82.9% of the initial adsorption ability after four cycles. Adsorption capacity of vanadium was lower than 1 mg/g for all samples. HPAO displayed very fast adsorption kinetics with an equilibrium at 60 min. The EDS results confirmed the low extraction of aluminum and vanadium provided by HPAO fibers. The gallium-loaded fiber could be effectively eluted by acidified thiourea. With proper control of the cross-linking duration by hydrazine, HPAO fiber with high selectivity towards gallium, high adsorption capacity and good recycle performance could be obtained, which is promising for recovering gallium needed for industrial applications.     

Preferential extraction of gallium from Bayer liquor using ion exchange chelating resin containing hydroxamic acid functional group

Gallium extraction studies were carried out using resin containing an hydroxamic acid functional group. Extraction was dependant on reaction time and alkali concentration. The resin did not extract aluminium. Vanadium extraction kinetics were slower than those of gallium. The gallium and vanadium separation efficiency increased with decreasing contact time with extractions of 64% and 32% respectively after 1 min. Gallium extraction was independent of alkali concentration up to 250 g dm^?3 and thereafter decreased with increasing alkali concentration. Vanadium extraction decreased with increasing alkali concentration. Cyclic batch and column studies were carried out with synthetic as well as actual Bayer liquor to test the stability and preferential extraction of gallium using the resin. It was observed that using resin partially loaded with gallium, the co‐extraction of vanadium could be minimised. Copyright © 2003 Society of Chemical Industry     

Uniform macroporous amidoximated polyacrylonitrile monoliths for gallium recovery from Bayer liquor

Efficient recovery of gallium from aqueous solution remains a problem to be solved in industry. Here a novel crosslinked monolith based on polyacrylonitrile/dimethyl sulfoxide (C-PAN) was prepared by thermally induced phase separation and supercritical CO₂ extraction drying technology. The influences of dissolution temperature and exchange solvents with different solubility parameters on the pore structure of C-PAN were systematically studied. It was found that the pore diameter decreased with the decrease of dissolution temperature and the increase of Δδ between exchange solvent and PAN. Meanwhile, the C-PAN with a small and dense pore structure showed better mechanical strength. Thereafter, the Ga³⁺ adsorption ability of amidoximated monolith (C-PAO) in simulated Bayer liquor was determined by batch tests. In the case of using methanol as the exchange solvent, the kinetic and equilibrium inspection study illustrated that both physical and chemical adsorption are present due to the multiscale and interconnected structure and the amidoxime groups. The adsorption capacity of C-PAO monolith toward gallium was 15.8 mg/g, with the equilibrium time as fast as 140 min, which can meet the requirement for the rapid extraction of gallium from Bayer liquor. It is expected that our work can provide some new ideas for fabricating gallium adsorbents.     

Preparation of Chelating Resins Containing a Pair of Neighboring Carboxylic Acid Groups and the Adsorption Characteristics for Heavy Metal Ions

Abstract

For the functional enhancement of chelating resins containing carboxylic acids, copolymer beads were prepared by suspension polymerization of styrene (St), methyl methacrylate (MMA), and divinylbenzene (DVB) in the presence of toluene as diluent. The phenyl rings of the beads were directly chloromethylated, and the carboxylic ester groups of the beads were converted into hydroxymethyl groups by reduction followed by chlorination to give chloromethyl groups, respectively. The chelating resins containing a pair of neighboring carboxylic acid groups (NCAGs) were obtained by the alkylation of chloromethyl groups in copolymer beads with diethyl malonate in the presence of sodium hydride followed by hydrolysis using aqueous alkali solution. Accordingly, the structural effects of the resins on the adsorption of heavy metal ions were investigated. Poly(St‐co‐DVB)‐based chelating resin containing NCAGs showed adsorption abilities toward heavy metal ions like Pb²⁺, Cd²⁺, and Cu²⁺, whereas poly(MMA‐co‐DVB)‐based chelating resin containing NCAGs showed adsorption abilities toward heavy metal ions like Cu²⁺, Cd²⁺, and Co²⁺. On the other hand, poly(St‐co‐MMA‐co‐DVB)‐based chelating resin containing NCAGs showed adsorption abilities toward heavy metal ions like Pb²⁺, Cd²⁺, Hg²⁺, Co²⁺, and Cu²⁺: a synergistic effect on the adsorption of heavy metal ions like Pb²⁺, Cd²⁺, Hg²⁺, and Co²⁺ was observed. The adsorption ability of poly(St‐co‐MMA‐co‐DVB)‐based chelating resin among three kinds of chelating resins was relatively good.     

Water‐swellable hydrophobic porous copolymer resins based on divinylbenzene and acrylonitrile. II. Pore structure and adsorption behavior

By using purified divinylbenzene (DVB, 98.8%) or technical DVB (79.3%), the hydrophobic, but water‐wettable or swellable porous copolymer resins based on DVB and acrylonitrile (AN) could be prepared with a wide range of pore structures under certain conditions. The specific surface area for the resulting AN/DVB resin, with an AN/DVB ratio of 40/60 (by mole), could reach a value of 704 m²/g, while such a resin is still water wettable or swellable by direct contact with water. The adsorption behavior of the AN/DVB resins was investigated by focusing on the comparison between the resins with and without prewetting, using caffeine and phenol as model adsorbates. Adsorption behavior of the AN/DVB resins, without prewetting, correlates well with the wetting ability of the resins in water, suggesting that a well water‐wettable hydrophobic porous AN/DVB resin could be directly applied, in a dry state, to the adsorption in an aqueous medium, almost without diminishing the ability of the resin to adsorb the solutes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2050–2056, 2004     

Functional,uniform, and macroporous latex particles: Preparation,electron microscopic characterization,and nonspecific protein adsorption properties

A series of uniform, macroporous particles with different surface chemistries were prepared with different acrylic comonomers [methyl methacrylate (MMA), butyl methacrylate (BMA), epoxypropyl methacrylate (EPMA), 2‐hydroxyethyl methacrylate (HEMA), and methacrylic acid (MAA)] with styrene–divinylbenzene (S–DVB) in a multistep seeded polymerization. In the synthesis, uniform polystyrene seed particles 6.2 μm in size were swollen first with a low molecular weight organic agent and then with a monomer phase including an S–DVB mixture and a relatively polar acrylic monomer. Final macroporous particles approximately 10 μm in size were obtained by the repolymerization of the monomer phase in the swollen seed particles. Surface and bulk morphologies were investigated with scanning and transmission electron microscopy, respectively. Although highly porous particles could be achieved with relatively hydrophobic monomers such as styrene, BMA, MMA, and EPMA, the use of hydrophilic monomers such as HEMA and MAA led to the synthesis of uniform particles with lower macroporosity. A comparison of Fourier transform infrared and Fourier transform infrared/diffuse reflectance spectroscopy spectra indicated that the concentration of polar acrylic monomer on the surface was higher than in the bulk structure. The nonspecific protein adsorption behavior of uniform, macroporous particles was investigated with albumin as a model protein. The highest nonspecific albumin adsorption was observed with plain poly(styrene‐co‐divinylbenzene) [poly(S–DVB)] particles. The particles produced with MMA and EPMA also exhibited albumin adsorption capacities very close to that of plain poly(S–DVB). Reasonably low nonspecific albumin adsorption was observed with the particles produced in the presence of MAA, HEMA, and BMA. Poly(S–DVB) particles functionalized with poly(vinyl alcohol) provided nearly zero nonspecific albumin adsorption. For nonspecific albumin binding onto the particles via a physical adsorption mechanism, desorption ratios higher than 80% could be achieved. The desorption ratio with the EPMA‐carrying particles was only 5% because the albumin adsorption onto EPMA‐carrying particles occurred predominantly with covalent‐bond formation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 414–429, 2002; DOI 10.1002/app.10412     

Synthesis and performance characteristics of methylmethacrylate–divinylbenzene copolymer-based chelating resin for gallium metal recovery

A chelating ion exchange resin based on a methylmethacrylate and divinylbenzene copolymer has been designed through suspension polymerisation and subsequent functionalisation to hydroxamic acid as chelating group. The chelating resin has been characterized by infrared spectroscopy, its particle size, stability in acid/alkaline media, specific gravity and its use in gallium recovery. The use of resin has been demonstrated to effect gallium recovery with an efficiency of about 80%.     

辐射法制备吸油树脂及其对典型有机化学品吸附性能研究

将聚合单体丙烯酸异辛酯(EHA)和化学交联剂苯二乙烯(DVB)溶于环己烷,通过γ射线引发聚合制备吸油树脂,并采用热重分析(TGA)和傅里叶红外光谱(FTIR)对树脂热稳定性和官能团进行分析.在此基础上,通过吸附实验系统研究吸油树脂对脂肪烃、芳香烃、酮类、醋酸酯类、醚类、卤代烃以及燃料油等典型有机化学品的吸附性能.结果表...     

Emulsion polymerisation of styrene in the presence of hydrocarbon diluents

Results are given for the effects of four hydrocarbon diluents (benzene, toluene, ethylbenzene and cyclohexane) upon the rate of emulsion polymerisation of styrene at 50°C, upon the particle size of the resultant latex, and upon the intrinsic viscosity of the polymer produced. The aromatic diluents were found to have a much greater effect in reducing the rate of polymerisation than can be accounted for by mere dilution of the monomer. For these diluents, the rate of polymerisation is approximately third order in initial concentration of monomer in the oil phase as a whole. Cyclohexane is far less effective as a retarder of polymerisation, the rate being approximately first order in monomer concentration in the oil phase. Particle size determinations indicate that the reductions in rate are due primarily to a reduction in the rate of polymerisation at each locus, rather than to a reduction in the number of reaction loci. The intrinsic viscosity of the polymer produced tends to fall with the rate of polymerisation. These observations are consistent with the view that aromatic diluents cause severe retardation of polymerisation because they diminish the Trommsdorff ‘gel’ effect at the reaction loci. This view is in turn shown to be consistent with a reaction mechanism in which, in the case of styrene-rich systems at least, the growing polymer particles do not attain equilibrium with the monomer droplets.