共查询到19条相似文献,搜索用时 93 毫秒
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利用反相悬浮结合溶剂结晶致孔法制备了具有超大孔隙、球形度良好的聚丙烯酰胺晶胶微球,晶胶微球平均粒径为234.1μm,孔径约为10~50μm。采用原位接枝法,将2-丙烯酰胺基-2-甲基-1-丙烷磺酸(AMPSA)接枝到晶胶微球孔隙表面上,得到了带有磺酸基团的阳离子交换晶胶微球。考察了晶胶微球的生物相容性和吸附蛋白质及重金属离子Cu2+的性能,结果表明:在大肠杆菌培养液中,添加晶胶微球,对大肠杆菌的生长影响不大。接枝了AMPSA的晶胶微球表现出更强的吸附Cu2+的能力,吸附容量达到1.14 mmol·g-1。同时,接枝后的晶胶微球也具有一定吸附蛋白质的能力,溶菌酶的吸附容量达到54.5 mg·g-1。因此,该大孔晶胶可望在微生物固定化、生物分离和重金属离子吸附中会发挥更大的作用。 相似文献
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以废弃物柚子皮为原料,制备了廉价、高效的生物炭微球吸附剂(BC、BC500),进行了对重金属铅离子的吸附实验。利用SEM、XRD、BET、FTIR及XPS等方法检测了吸附剂的物化特性。研究了溶液pH值和吸附剂添加量对铅离子吸附特性的影响,同时对吸附等温线及吸附动力学进行了分析研究。结果表明:生物炭吸附剂吸附的最优条件为pH=5和吸附剂添加量为20 mg。BC和BC500对铅离子的吸附更符合Langmuir吸附等温线方程,占据主导地位的是化学吸附而非物理吸附。 相似文献
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壳聚糖固化单宁微球的制备及其吸附性能 总被引:3,自引:1,他引:2
5 g单宁酸与10 g壳聚糖微球在100 mL pH=7的溶液中反应6 h,再用0.06 mol/L环氧氯丙烷在pH=10,50℃反应4 h制得壳聚糖固化单宁微球,每克壳聚糖微球固载单宁量为0.27 g。采用扫描电镜和红外光谱对微球进行了表征,考察了微球的溶胀性能及对金属离子的吸附性能。研究表明,通过此法制得的壳聚糖固化单宁微球具有表面粗糙,内部疏松多孔的结构。与壳聚糖微球相比,壳聚糖固化单宁微球在溶液中的溶胀性减小,在pH=5及9时,分别减小了63%和50%。对金属离子的吸附容量增大,对Cd2+的吸附容量从0.6 mmol/g提高到2.2 mmol/g,提高了2.66倍。 相似文献
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以β-环糊精(β-CD)为原料,环氧氯丙烷(ECH)作为交联剂,采用反相乳液聚合法制备了β-环糊精聚合物微球(β-CDPM)。研究了水溶液中β-CDPM对1,4-对苯二酚的吸附性能。结果表明,β-CDPM对1,4-对苯二酚的吸附平衡时间为2 h,其吸附行为与一级吸附动力学模型和二级吸附动力学模型都有较好拟合,相关系数为0.906 4和0.983 16。在30,40,50℃下吸附等温线符合弗朗德里希方程,且在不同温度下拟合得到的1/n分别为:0.925 02,1.009 39和0.974 48,基本上都小于1,属优惠吸附;随时间的延长,脱附量不断增大,72 h后基本达到平衡。 相似文献
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采用原位接枝法,将3-烯丙氧基-2-羟基-1-丙磺酸钠(AHPSA)接枝到聚丙烯酰胺基晶胶基质孔隙内表面,制备得到了阳离子交换型连续床用的带磺酸基超大孔晶胶介质.通过脉冲示踪法测量停留时间分布(RTD),得到了晶胶介质的理论等板高度(HETP).通过测量一定压差下流经晶胶床柱的液量,得到晶胶介质的渗透率.用溶菌酶作为模型蛋白测量晶胶介质的吸附容量.考察了单体浓度、接枝反应时间等反应条件对晶胶介质的HETP、渗透率、蛋白质吸附容量等性能的影响.结果表明:接枝AHPSA的阳离子交换晶胶介质的HETP基本不受接枝反应时间和单体浓度的影响,其渗透率随接枝反应时间增大略有减小,其对溶菌酶的吸附容量与接枝单体的浓度成正比,受接枝反应时间的影响较小. 相似文献
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以偏高岭土和改性水玻璃为原料,采用分散悬浮固化法制备偏高岭土基地质聚合物微球(GM)。使用扫描电子显微镜、比表面积及孔径分布测试仪、傅里叶变换红外光谱仪和X射线粉末衍射仪对其进行了表征,并研究了GM对亚甲基蓝的吸附性能。结果表明,GM对亚甲基蓝的吸附基本符合准二级动力学模型和Langmuir吸附等温线模型,333 K时理论最大吸附量为100.1 mg/g。GM对亚甲基蓝的吸附是自发吸热过程。GM在5次循环利用后,对MB的去除率仍可达81.56%,并易于回收和再生。分析了GM对不同阴阳离子型染料的吸附效果,结果表明,GM对阳离子型染料具有选择性吸附。GM是一种低价、有效、绿色、可循环利用的吸附剂,可用于去除水中阳离子型染料污染物。 相似文献
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利用氨基硅烷偶联剂(KH-792)对松香基羟基化聚合物微球进行接枝改性,研究了反应温度、反应时间和KH-792用量对聚合物微球性能的影响。利用红外光谱(FTIR)、热重分析(TGA)、扫描电镜(SEM)和X-射线光电子能谱(XPS)对聚合物微球进行测试表征,利用电导滴定法测定了聚合物微球的氨基含量。探讨了不同氨基含量的聚合物微球对乙基紫的吸附作用。结果表明:成功制备了松香基氨基化聚合物微球,改性前后聚合物微球形态均无明显变化且球形及单分散性好,热稳定性高于松香基羟基化聚合物微球。较优制备条件为:KH-792用量为松香基羟基化聚合物微球质量的70%,在90℃下反应10h,聚合物微球氨基含量达到181μmol/g。当固液比为1 g/L,pH=9.5,在328 K下吸附5min时,微球对乙基紫的吸附量为57.02 mg/g。 相似文献
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Polymer beads, particularly supermacroporous beads, play important roles in biotechnological applications, such as their application as adsorbents in bioseparation processes and used as carriers in immobilization of cells or/and enzymes. In this study, supermacroporous polyacrylamide (pAAm) based cryogel beads were prepared via an inverse suspension polymerization method at low temperature (<0°C). Standard porous beads were also prepared at room temperature for comparison. The results showed that the diameter of the beads were in the range of 50–400 μm and some irregular large pores of the beads were of 3–90 μm in diameter, which had good biocompatibility, hydrophilicity, high porosity and large connected pores. To modify the properties of these cryogel beads, cryogel beads embedded with nanoparticles of TiO2 were also prepared. The physical properties of the composite cryogel beads with supermacroporous were characterized and the results showed an improvement in mechanical strength and stability, which indicated that these supermacroporous cryogel beads may be useful in biotechnological applications as the networks in the beads can facilitate the mass transfer of nutrients and oxygen. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3082–3089, 2013 相似文献
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利用冰冻凝胶(cryogel,简称冰胶)印迹聚合物实现了脂肪酶的固定化.在脂肪酶存在的条件下,以过硫酸铵/亚硫酸氢钠为引发剂,由丙烯酰胺、N,N-亚甲基双丙烯酰胺、丙烯酸、烯丙胺共聚而得到印迹聚合物固定化酶.通过催化三油酸甘油酯与甲醇的酯交换反应,发现冰胶固定化脂肪酶、常规凝胶固定化脂肪酶、游离脂肪酶具有相似的催化性能.冰胶固定化酶与相应的凝胶固定化酶显示出类似的稳定性,而传质方面则优于常规凝胶固定化酶,因此冰胶印迹聚合物固定化有望成为一种具有吸引力的酶固定化方法. 相似文献
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This work has demonstrated that the novel chitosan derivative, synthesized by phase transition and grafting diethylenetriamine, has a great potential for the adsorption of acid dyes from aqueous solutions. Four acid dyes with different molecular sizes and structures were used to investigate the adsorption performance of diethylenetriamine‐modified chitosan beads (CTSN‐beads). Results indicated that the adsorption of dyes on CTSN‐beads was largely dependent on the pH value and controlled by the electrostatic attraction. In addition, the adsorption rate (AO10 > AO7 > AR18 > AG25) and adsorption capacities (AO7 > AR18 > AO10 > AG25) were directly related to the molecular size of the dye and the amount of the sulfonate groups on the dye molecules. The equilibrium and kinetic data fitted well with the Langmuir–Freundlich and pseudo‐second‐order model. Furthermore, thermodynamic parameters indicated that the adsorption processes occurred spontaneously and higher temperature made the adsorption easier. The reuse tests indicated that the CTSN‐beads can be recovered for multiple uses. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4090–4098, 2013 相似文献
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Shao‐Jung Wu Tzong‐Horng Liou Chao‐Hsien Yeh Fwu‐Long Mi Tsung‐Kuan Lin 《应用聚合物科学杂志》2013,127(6):4573-4580
Porous chitosan–tripolyphosphate beads, prepared by the ionotropic crosslinking and freeze‐drying, were used for the adsorption of Cu(II) ion from aqueous solution. Batch studies, investigating bead adsorption capacity and adsorption isotherm for the Cu(II) ion, indicated that the Cu(II) ion adsorption equilibrium correlated well with Langmuir isotherm model. The maximum capacity for the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, deduced from the use of the Langmuir isotherm equation, was 208.3 mg/g. The kinetics data were analyzed by pseudo‐first, pseudo‐second order kinetic, and intraparticle diffusion models. The experimental data fitted the pseudo‐second order kinetic model well, indicating that chemical sorption is the rate‐limiting step. The negative Gibbs free energy of adsorption indicated a spontaneous adsorption, while the positive enthalpy change indicated an endothermic adsorption process. This study explored the adsorption of Cu(II) ion onto porous chitosan–tripolyphosphate beads, and used SEM/EDS, TGA, and XRD to examine the properties of adsorbent. The use of porous chitosan–tripolyphosphate beads to adsorb Cu(II) ion produced better and faster results than were obtained for nonporous chitosan–tripolyphosphate beads. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Zhaoping Hou Xinhe Yang Zihan Tian Liangliang Liu 《International Journal of Applied Ceramic Technology》2023,20(5):2737-2746
Porous Al2O3 ceramic beads with a small-scale lamellar pore structure were prepared by the dripping-ice templating method. The densification behavior of lamellar walls and the attrition resistance of porous Al2O3 beads were investigated. For the two-dimensional structural lamellar walls, the intrinsic pores shrunk, and the necking area grew during the sintering process, leading to the densification of lamellar walls and the shrinking of porous beads. In addition, the two-dimensional lamellar walls and three-dimensional Al2O3 bulk are compared and possibilities of elaborating of the discrepancy in grain size and pore morphology are discussed. Attrition resistance was determined by a grinding test. The dominant attrition mechanism of porous Al2O3 beads is abrasion. High sintering temperature led to a decrease in the attrition rate due to a wider necking area and denser pore walls. 相似文献
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Krishankant Singh Chetan Shah Charu Dwivedi Manmohan Kumar Parma N. Bajaj 《应用聚合物科学杂志》2013,127(1):410-419
Polyacrylonitrile beads, containing the amidoximated polyacrylonitrile, were prepared for adsorption of uranium. The synthesized amidoximated polyacrylonitrile chelating beads were evaluated, for their ability to adsorb uranium from aqueous solution, at different temperatures and pH values. The kinetic measurement showed that about 120 min of equilibration time was enough, to remove saturation amount of uranium from the solution. The pseudo first‐order and pseudo second‐order equations were used to analyze the kinetic data, and the rate constants were determined. The equilibrium adsorption data were examined by the Langmuir, Freundlich, and Temkin isotherms. The data showed a better fit to the Langmuir isotherm. The loaded uranium could also be leached out from the beads, by treating with dilute acids. The uranium uptake capacity of the polymeric beads was found to be 3.5 mg/g of the swollen beads. Reusability of the beads was also established by multiple adsorption–desorption experiments. The pore volume and the surface area of the dried beads, measured by BET method, were found to be 1.93 cc/g and 320 m2/g, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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研究了金属有机骨架材料MIL-101表面印迹聚合物的制备方法及其吸附行为。以MIL-101为载体,先通过化学修饰氨基制备了ED-MIL-101材料,再以京尼平苷为模板,甲基丙烯酸为功能单体,二乙烯基苯为交联剂,表面接枝京尼平苷分子印迹聚合物制备了MIPs@MIL-101印迹聚合物。通过傅里叶红外光谱(FTIR)、X射线衍射光谱(XRD)、扫描电镜(SEM)对聚合物进行结构表征,测试了聚合物的等温吸附及吸附动力学性能,探讨了聚合物的固相萃取性能。红外光谱及XRD衍射分析表明了MIL-101氨基化修饰及表面接枝复合材料的成功制备。吸附动力学研究表明当分子印迹聚合物用于吸附京尼平苷时,可在270min内达到吸附平衡。当温度为298K、308K、318K、328K时,印迹聚合物对模板的吸附量分别为55.94mg/g、46.16mg/g、38.98mg/g、31.47mg/g。吸附热ΔH为26.997kJ/mol。分子印迹固相萃取杜仲提取物中的京尼平苷时,总回收率达95.0%。 相似文献