Preparation and characterization of PVDF-glass fiber composite membrane reinforced by interfacial UV-grafting copolymerization

A novel inorganic–organic composite membrane,namely poly(vinylidene fluoride) PVDF-glass fiber(PGF) composite membrane,was prepared and reinforced by interfacial ultraviolet(UV)-grafting copolymerization to improve the interfacial bonding strength between the membrane layer and the glass fiber.The interfacial polymerization between inorganic–organic interfaces is a chemical cross-linking reaction that depends on the functionalized glass fiber with silane coupling(KH570) as the initiator and the polymer solution with acrylamide monomer(AM) as the grafting block.The Fourier transform infrared spectrometer-attenuated total reflectance(FTIR-ATR) spectra and the energy dispersive X-ray(EDX) pictures of the interface between the glass fiber and polymer matrix confirmed that the AM was grafted to the surface of the glass fiber fabric and that the grafting polymer was successfully embedded in the membrane matrix.The formation mechanisms,permeation,and anti-fouling performance of the PGF composite membrane were measured with different amounts of AM in the doping solutions.The results showed that the grafting composite membrane improved the interfacial bonding strength and permeability,and the peeling strength was improved by 32.6% for PGF composite membranes with an AM concentration at 2 wt.%.     

Sorbents with high efficiency for CO2 capture based on amines-supported carbon for biogas upgrading

Sorbents for CO_2 capture have been prepared by wet impregnation of a commercial active carbon(Ketjen-black, Akzo Nobel) with two CO_2-philic compounds, polyethylenimine(PEI)and tetraethylenepentamine(TEPA), respectively. The effects of amine amount(from 10 to70 wt.%), CO_2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO_2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N_2 adsorption–desorption,scanning electron microscopy and energy dispersive X-ray(SEM/EDX). A promising CO_2 sorption capacity of 6.90 mmol/gsorbenthas been obtained with 70 wt.% of supported TEPA at 70℃ under a stream containing 80 vol% of CO_2. Sorption tests, carried out with simulated biogas compositions(CH_4/CO_2mixtures), have revealed an appreciable CO_2 separation selectivity; stable performance was maintained for 20 adsorption–desorption cycles.     

Advanced treatment of wet-spun acrylic fiber manufacturing wastewater using three-dimensional electrochemical oxidation

A three-dimensional electrochemical oxidation(3D-EC) reactor with introduction of activated carbon(AC) as particle micro-electrodes was applied for the advanced treatment of secondary wastewater effluent of a wet-spun acrylic fiber manufacturing plant. Under the optimized conditions(current density of 500 A/m~2, circulation rate of 5 mL/min, AC dosage of 50 g, and chloride concentration of 1.0 g/L), the average removal efficiencies of chemical oxygen demand(COD_(cr)), NH3–N, total organic carbon(TOC), and ultraviolet absorption at 254 nm(UV_(254)) of the 3D-EC reactor were 64.5%, 60.8%, 46.4%, and 64.8%, respectively; while the corresponding effluent concentrations of COD_(cr), NH_3–N, TOC, and UV_(254) were 76.6, 20.1, and42.5 mg/L, and 0.08 Abs/cm, respectively. The effluent concentration of COD_(cr) was less than 100 mg/L, which showed that the treated wastewater satisfied the demand of the integrated wastewater discharge standard(GB 8978-1996). The 3D-EC process remarkably improved the treatment efficiencies with synergistic effects for COD_(cr), NH_3–N, TOC, and UV_(254) during the stable stage of 44.5%, 38.8%, 27.2%, and 10.9%, respectively, as compared with the sum of the efficiencies of a two-dimensional electrochemical oxidation(2D-EC) reactor and an AC adsorption process, which was ascribed to the numerous micro-electrodes of AC in the 3D-EC reactor. Gas chromatography mass spectrometry(GC–MS) analysis revealed that electrochemical treatment did not generate more toxic organics, and it was proved that the increase in acute biotoxicity was caused primarily by the production of free chlorine.     

CO2 capture performance of bi-functional activated bleaching earth modified with basic-alcoholic solution and functionalization with monoethanolamine: isotherms, kinetics and thermodynamics

CO_2 capture performance of bifunctional activated bleaching earth(ABE) was investigated at atmospheric pressure. The sorbents were characterized by means of X-ray diffraction(XRD), Brunauer–Emmett–Teller(BET), Caron-Hydrogen-Nitrogen analysis(CHN), Fourier transform infrared(FT-IR) and thermal gravimetric analysis(TGA). The CO_2 capacity was enhanced via basic-modification and monoethanolamine(MEA) loading of the ABE sorbent to obtain a bifunctional surface property. Here, basic-modified calcined ABE with a 30 wt.%MEA loading(SAB-30) showed the highest CO_2 capture capacity, but this was decreased with excess MEA loading( 30 wt.%). At a 10%(V/V) initial CO_2 concentration feed, the maximum capacity of SAB-30 increased from 2.71 mmol/g at 30℃(without adding moisture to the feed) to 3.3 mmol/g at 50℃ when adding 10%(V/V) moisture to the feed. Increasing the moisture concentration further reduced the maximum CO_2 capacity due to the blocking effect of the excess moisture on the sorbent surface. However, SAB-30 could completely capture CO_2 even in a 100%(V/V) initial CO_2 concentration feed. A maximum CO_2 capacity of5.7 mmol/g for SAB-30 was achieved at 30℃. Varying the ratio of sorbent weight to total flow rate of the gas stream had no discernible effect on the equilibrium CO_2 capture capacity. Avrami's equation and Toth's isotherm model provided a good fitting for the data and suggested the presence of more than one reaction pathway in the CO_2 capture process and the heterogeneous adsorption surface of SAB-30. Thermodynamics studies revealed that CO_2 capture on the bifunctional SAB-30 is feasible, spontaneous and exothermic in nature.     

聚离子液体刷接枝改性PVDF膜及其对药物硫酸氢氯吡咯雷分离性能研究

以聚偏氟乙烯(PVDF)超滤膜为底膜,通过浸渍法使多巴胺(DOPA)在膜表面形成聚多巴胺(PDOPA)层,然后由化学反应固定溴代卤化物,并通过原子转移自由基聚合(ATRP)反应在膜表面接枝聚离子液体刷(PBIVm-Br),以制备聚离子液体刷改性PVDF膜,即PVDF-g-PBIVm-Br膜.结果表明,改性PVDF膜的接触角下降至60°以下且显示出良好的荷正电性.改性膜的药物通量和截留率均大于未改性PVDF膜,分离10 mg·L~(-1)的硫酸氢氯吡咯雷时,改性膜(M4)的药物通量可达27.62 L·m~(-2)·h~(-1),截留率为89.03%,通量恢复率为95.32%.经过60 h分离实验后,膜M4对硫酸氢氯吡咯雷溶液的分离通量维持在18.05 L·m~(-2)·h~(-1),截留率从89.03%上升到92.19%.以上结果表明,聚离子液体刷改性膜在荷正电有机污染物的分离方面具有一定的应用前景.     

Bioaccumulation characterization of uranium by a novel Streptomyces sporoverrucosus dwc-3

The biosorption mechanisms of uranium on an aerobic bacterial strain Streptomyces sporoverrucosus dwc-3, isolated from a potential disposal site for (ultra-)low uraniferous radioactive waste in Southwest China, were evaluated by using transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), proton induced X-ray emission (PIXE) and enhanced proton backscattering spectrometry (EPBS). Approximately 60% of total uranium at an initial concentration of 10 mg/L uranium nitrate solution could be absorbed on 100 mg S. sporoverrucosus dwc-3 with an adsorption capacity of more than 3.0 mg/g (wet weight) after 12 hr at room temperature at pH 3.0. The dynamic biosorption process of S. sporoverrucosus dwc-3 for uranyl ions was well described by a pseudo second-order model. S. sporoverrucosus dwc-3 could accumulate uranium on cell walls and within the cell, as revealed by SEM and TEM analysis as well as EDX spectra. XPS and FT-IR analysis further suggested that the absorbed uranium was bound to amino, phosphate and carboxyl groups of the cells. Additionally, PIXE and EPBS results confirmed that ion exchange also contributed to the adsorption process of uranium.     

Performances of biological aerated filter employing hollow fiber membrane segments of surface-improved poly （sulfone） as biofilm carriers

Using the surface of poly （sulfone） hollow fiber membrane segments as grafted layer, the hydrophilic acrylamide chain was grafted on by UV-photoinduced grafting polymerization. The gained improvement of surface wettability for the modified membrane was tested by measuring the contact-angle as well as FTIR spectra. Then correlation between the hydrophilic ability of support material and the biofilm adherence ability was demonstrated by comparing the pollutant removal rates from urban wastewater via two identical lab-scale up-flow biological aerated filters, one employed the surface wettability modified poly （sulfone） hollow fiber membrane segment as biofilm carder and the other employed unmodified membrane segment as biofilm carder. The experimental results showed that under the conditions of influent flux 5 L/h, hydraulic retention time 9 h and gas to liquid ratio （G/L） 10： 1, the removal rates of chemical oxygen demand （COD） and ammonium nitrogen （NH4^＋-N） for the modified packing filter and the unmodified packing filter was averaged at 83.64% and 96.25%, respectively, with the former filter being 5%-20% more than the latter. The effluent concentration of COD, NH4^＋-N and turbidity for the modified packing filter was 25.25 mg/L, 2 mg/L and 8 NTU, respectively. Moreover, the ammonium nitrogen removal performance of the filter packing the modified PSF was compared with the other bioreactor packing of an efficient floating medium. The biomass test indicated that the modified membrane matrixes provided better specific adhesion （3310-5653 mg TSS/L support）, which gave a mean of 1000 mg TSS/L more than the unmodified membrane did. In addition, the phenomenon of simultaneous denitrification on the inner surface of the support and nitrification on the outer surface was found in this work.     

Emissions from the combustion of eucalypt and pine chips in a fluidized bed reactor

Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution,reduced costs and improved efficiency of technologies.Under the European Union(EU)energy directive,biomass is a suitable renewable source.The aim of this study was to experimentally quantify and characterize the emission of particulate matter(PM_(2.5))resulting from the combustion of two biomass fuels(chipped residual biomass from pine and eucalypt),in a pilot-scale bubbling fluidized bed(BFB)combustor under distinct operating conditions.The variables evaluated were the stoichiometry and,in the case of eucalypt,the leaching of the fuel.The CO and PM_(2.5)emission factors were lower when the stoichiometry used in the experiments was higher(0.33±0.1 g CO/kg and 16.8±1.0 mg PM_(2.5)/kg,dry gases).The treatment of the fuel by leaching before its combustion has shown to promote higher PM_(2.5)emissions(55.2±2.5 mg/kg,as burned).Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass,while carbonate(CO_3~(2-))accounted for between 2.3 and 8.5 wt.%.The particulate mass was mainly composed of inorganic matter(71% to 86% of the PM_(2.5)mass).Compared to residential stoves,BFB combustion generated very high mass fractions of inorganic elements.Chloride was the water soluble ion in higher concentration in the PM_(2.5)emitted by the combustion of eucalypt,while calcium was the dominant water soluble ion in the case of pine.     

Beijing Tong Ren Tang Company Limited Scientific Research Institute, Beijing 100011, China

By dynamic method under UV irradiation,commercial melt-blown polypropylene(PPMB)filter element was modified with acrylamide(AAm)using benzophenone(BP)as initiator.Attenuated total reflection-Fourier transform infrared spectroscopy and scanning electron microscope verified that polyacrylamide chain was grafted on the fiber surface of PPMB filter element.Elemental content analysis with energy dispersive X-ray of fibers revealed that the polymerization content in the inner part of filter element was relatively higher than that in the outer.Degree of grafting changed with initiator concentration,monomer concentration,reaction temperature and reached 2.6% at the reaction condition:C_(BP)=0.06 mol/L,C_(AAm)=2.0 mol/L,irradiation time:80 min,temperature: 60℃.Relative water flux altered with the hydrophilicity and pore size of filter element.In the antifouling test,the modified filter gave greater flux recovery(approximately 70%)after filtration of the water extract of Liuweidihuang,suggesting that the fouling layer was more easily reversible due to the hydrophilic nature of the modified filter.     

Metal distribution characteristic of MSWI bottom ash in view of metal recovery

Bottom ash is the major by-product of municipal solid waste incineration(MSWI), and is often reused as an engineering material, such as road-base aggregate. However, some metals(especially aluminum) in bottom ash can react with water and generate gas that could cause expansion and failure of products containing the ash; these metals must be removed before the ash is utilized. The size distribution and the chemical speciation of metals in the bottom ash from two Chinese MSWI plants were examined in this study, and the recovery potential of metals from the ash was evaluated. The metal concentrations in these bottom ashes were lower than that generated in other developed countries. Specifically, the contents of Al,Fe, Cu and Zn were 18.9–29.2, 25.5–32.3, 0.7–1.0 and 1.6–2.5 g/kg, respectively. Moreover,44.9–57.0 wt.% of Al and 55.6–75.4 wt.% of Fe were distributed in bottom ash particles smaller than 5 mm. Similarly, 46.6–79.7 wt.% of Cu and 42.9–74.2 wt.% of Zn were concentrated in particles smaller than 3 mm. The Fe in the bottom ash mainly existed as hematite, and its chemical speciation was considered to limit the recovery efficiency of magnetic separation.     

Effects of silver adsorbed on fumed silica, silver phosphate glass, bentonite organomodified with silver and titanium dioxide in aquatic indicator organisms

In order to reduce the level of transmission of diseases caused by bacteria and fungi, the development of antimicrobial additives for use in personal care, hygiene products, clothing and others has increased. Many of these additives are based on metals such as silver and titanium. The disposal of these products in the environment has raised concerns pertaining to their potential harmfulness for beneficial organisms. The objective of this study was to evaluate the influence of the shape, surface chemistry, size and carrier of three additives containing silver and one with titanium dioxide (TiO₂) on microcrustacean survival. Daphnia magna was used as a bioindicator for acute exposure test in suspensions from 0.0001 to 10,000 ppm. Ceriodaphnia dubia was used for chronic test in TiO₂ suspensions from 0.001 to 100 ppm. D. magna populations presented high susceptibility to all silver based additives, with 100% mortality after 24 hr of exposure. A different result was found in the acute experiments containing TiO₂ suspensions, with mortality rates only after 48 hr of incubation. Even on acute and chronic tests, TiO₂ did not reach a linear concentration-response versus mortality, with 1 ppm being more toxic than 10,000 ppm on acute test and 0.001 more toxic than 0.01 ppm on chronic assay. Silver based material toxicity was attributed to silver itself, and had no relation to either form (nano or ion) or carrier (silica, phosphate glass or bentonite). TiO₂ demonstrated to have a low acute toxicity against D. magna.     

Hydrothermal fabrication of selectively doped organic assisted advanced ZnO nanomaterial for solar driven photocatalysis

Hydrothermal fabrication of selectively doped (Ag⁺ + Pd^3 +) advanced ZnO nanomaterial has been carried out under mild pressure temperature conditions (autogeneous; 150°C). Gluconic acid has been used as a surface modifier to effectively control the particle size and morphology of these ZnO nanoparticles. The experimental parameters were tuned to achieve optimum conditions for the synthesis of selectively doped ZnO nanomaterials with an experimental duration of 4 hr. These selectively doped ZnO nanoparticles were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV–Vis spectroscopy and scanning electron microscopy (SEM). The solar driven photocatalytic studies have been carried out for organic dyes, i.e., Procion MX-5B dye, Cibacron Brilliant Yellow dye, Indigo Carmine dye, separately and all three mixed, by using gluconic acid modified selectively doped advanced ZnO nanomaterial. The influence of catalyst, its concentration and initial dye concentration resulted in the photocatalytic efficiency of 89% under daylight.     

聚离子液体修饰荷电超滤复合膜的构建及其抗污染性分析

以氯化-1-烯丙基-3-乙烯基咪唑离子液体为反应单体,偶氮二异丁腈(AIBN)为引发剂,通过自由基聚合先合成聚离子液体预聚物,并将其与聚偏氟乙烯(PVDF)、聚乙二醇(PEG)进一步共混反应,以制备聚离子液体/PVDF共混铸膜液.然后将该铸膜液在聚丙烯(PP)微孔膜表面进行涂覆成膜,以制备具有互穿网络结构的聚离子液体/PVDF荷电复合膜.采用红外光谱、扫描电镜、Zeta电位计等对复合膜表面的化学结构、形貌及荷电性能等进行分析,并采用水通量测定仪对复合膜的纯水通量及蛋白质和染料的分离性能等进行了研究.结果表明,该复合膜表面具有较好的荷电性能,且随聚离子液体的加入可以有效提高膜的亲水性和抗污染性,复合膜M2的纯水通量可达到101.7 L·m-2·h-1,该膜对溶菌酶和染料罗丹明6G的截留率分别为88.0%和94.1%,该分离膜经清水反冲洗后通量恢复率分别达到72.5%和91.8%.     

Gas-initiation under UV and liquid-grafting polymerization on the surface of polysulfone hollow fiber ultrafiltration membrane by dynamic method

Using the inner-surface of polysulfone hollow fiber ultrafiltration membranes as grafted layer, the method of gas-initiation and liquid-polymerization has been studied, which aimed to adjust the diameter of the pores in the membranes. The degree of polymerization varied with the changes of the parameters, such as irradiation time, monomer concentration, temperature and time of polymerization and so on. The results indicated that using benzophenone(BP) which is in a gaseous condition as photo-initiator, acrylamide as graft monomer, the polyacrylamide chain was grafted on the surface of membranes. After the surface membrane being modified, the water flux and retention altered, and thus it can be seen that the diameter of the pores in the membrane was altered. These experiments contribute to finding a new way to produce the hollow fiber membrane with the small pore size and are extraordinarily worth developing and studying.     

Drinking water treatment using a submerged internal-circulation membrane coagulation reactor coupled with permanganate oxidation

A submerged internal circulating membrane coagulation reactor(MCR) was used to treat surface water to produce drinking water. Polyaluminum chloride(PACl) was used as coagulant,and a hydrophilic polyvinylidene fluoride(PVDF) submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure(TMP), zeta potential(ZP) of the suspended particles in raw water, and KMnO_4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China(GB 5749-2006), as evaluated by turbidity(1 NTU) and total organic carbon(TOC)(5 mg/L)measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon(DOC) in the raw water also increased with increasing TMP in the range of 0.01–0.05 MPa. High ZP induced by PACl, such as 5–9 mV, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity.However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1–2 mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO_4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes.     

Visible light driven mineralization of spiramycin over photostructured N-doped TiO2 on up conversion phosphors

A novel visible light-active photocatalyst formulation(NdT/OP) was obtained by supporting N-doped TiO_2(NdT) particles on up-conversion luminescent organic phosphors(OP). The photocatalytic activity of such catalysts was evaluated for the mineralization process of spiramycin in aqueous solution. The effect of NdT loading in the range 15–60 wt.% on bulk and surface characteristics of NdT/OP catalysts was investigated by several chemicophysical characterization techniques. The photocatalytic performance of NdT/OP catalysts in the removal of spyramicin from aqueous solution was assessed through photocatalytic tests under visible light irradiation. Total organic carbon(TOC) of aqueous solution,and CO and CO_2 gas concentrations evolved during the photodegradation were analyzed. A dramatic enhancement of photocatalytic activity of the photostructured visible active NdT/OP catalysts,compared to NdT catalyst,was observed. Only CO_2 was detected in gas-phase during visible light irradiation,proving that the photocatalytic process is effective in the mineralization of spiramycin,reaching very high values of TOC removal. The photocatalyst NdT/OP at 30 wt.% of NdT loading showed the highest photocatalytic activity(58%of TOC removed after 180 min irradiation against only 31% removal after 300 min of irradiation of NdT). We attribute this enhanced activity to the high effectiveness in the utilization of visible light through improved light harvesting and exploiting. OP particles act as "photoactive support",able to be excited by the external visible light irradiation,and reissue luminescence of wavelength suitable to promote NdT photomineralization activity.     

LED联合玻璃纤维光催化填料对苯酚的降解研究

以钛酸四丁酯为原料,采用浸渍提拉法制备了负载TiO₂的玻璃纤维光催化填料,考察溶液初始pH值、苯酚初始浓度、UV-LED消耗功率以及曝气强度对光催化降解效果的影响.结果表明,在溶液pH=3、苯酚初始浓度为10mg/L、UV-LED输出功率为2.968W,曝气强度为1.8L/min时,光催化反应装置对苯酚的降解率可达97.05%,降解过程遵循准一级反应动力学.此外,该反应装置的能耗较低,催化剂负载的牢固性较好.     

Enhanced dechlorination of 2,4-dichlorophenol by recoverable Ni/Fe–Fe3O4 nanocomposites

Ni/Fe-Fe_3O_4 nanocomposites were synthesized for dechlorination of 2,4-dichlorophenol(2,4-DCP). The effects of the Ni content in Ni/Fe-Fe_3O_4 nanocomposites, solution pH, and common dissolved ions on the dechlorination efficiency were investigated, in addition to the reusability of the nanocomposites. The results showed that increasing content of Ni in Ni/Fe–Fe_3O_4 nanocomposites, from 1 to 5 wt.%, greatly increased the dechlorination efficiency; the Ni/Fe–Fe_3O_4 nanocomposites had much higher dechlorination efficiency than bare Ni/Fe nanoparticles. Ni content of 5 wt.% and initial p H below 6.0 was found to be the optimal conditions for the catalytic dechlorination of 2,4-DCP. Both 2,4-DCP and the intermediate product 2-chlorophenol(2-CP) were completely removed, and the concentration of the final product phenol was close to the theoretical phenol production from complete dechlorination of 20 mg/L of 2,4-DCP, after 3 hr reaction at initial p H value of 6.0,3 g/L Ni/Fe-Fe_3O_4 , 5 wt.% Ni content in the composite, and temperature of 22℃. 2,4-DCP dechlorination was enhanced by Cl-and inhibited by NO3-and SO_4~(2-). The nanocomposites were easily separated from the solution by an applied magnetic field. When the catalyst was reused, the removal efficiency of 2,4-DCP was almost 100% for the first seven uses, and gradually decreased to 75% in cycles 8–10. Therefore, the Ni/Fe–Fe_3O_4 nanocomposites can be considered as a potentially effective tool for remediation of pollution by 2,4-DCP.     

聚烯丙基磺酸钠接枝空心玻璃微珠的制备及其吸附性能研究

通过将烯丙基磺酸钠（SAS）和硅烷偶联剂接枝到空心玻璃微珠表面,制备出新型空心玻璃微珠基吸附剂（KNH-g-PSAS）并采用扫描电子显微镜,能量分散光谱,X射线光电子能谱,傅里叶变换红外光谱,热重分析和X射线衍射仪等对其进行了充分的表征,显示了SAS的成功接枝.此外,系统地研究了溶液的pH值,接触时间,初始浓度和温度对KNH-g-PSAS吸附阳离子染料的影响.准二级动力学模型和Langmuir等温线模型分别很好地描述了吸附动力学和吸附等温线,表明吸附是发生在吸附剂表面且均匀的单层吸附.吸附实验表明,在最佳条件下,KNH-g-PSAS对碱性品红、金胺O、结晶紫和孔雀石绿的吸附能力分别为2247.19mg/g,2317.46mg/g,2557.54mg/g,2808.98mg/g.KNH-g-PSAS具有出色的自上浮性能和回收表现.     

纳米聚丙烯-丙烯酸酯改性材料的制备及其吸油性能研究

以纳米聚丙烯(nano-polypropylene,PP)为基体,丙烯酸丁酯为单体,采用紫外辐射方法制备高吸油性复合材料(butyl acrylate grafted nano-polypropylene,BAPP)。试验确定的最佳制备条件为:辐照时间1 h,单体浓度33.3%,光敏剂浓度0.2%,并通过傅里叶变换红外光谱仪对改性前后样品的结构进行了表征,结果表明丙烯酸丁酯被成功接枝到纳米聚丙烯纤维上。考察了接枝率、吸附时间、吸附温度和pH值等对改性纳米聚丙烯材料吸油性能的影响,改性纳米聚丙烯对机油的吸附符合二级动力学模型。实验数据显示,常温下纳米聚丙烯和改性材料对原油的吸油量分别为35.5 g/g和28.5 g/g,改性后的材料吸油性能明显改善。温度对改性纳米聚丙烯纤维的吸油率有明显影响,与油品种类及粘度有关系,随着pH值的升高,改性纳米聚丙烯纤维对机油的吸油率迅速增加。