超大孔聚丙烯酰胺晶胶微球的制备及其生物相容性和吸附性能

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234.1 mm,孔径约为10～50 mm。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。     

混合模式介质的制备及用于清除抗体中蛋白A

针对抗体纯化过程中脱落蛋白A的清除,设计和制备了以N-苄基-N-甲基乙醇胺为功能配基的混合模式层析介质Adhere NUPharose FF,该配基兼有疏水、静电和氢键作用。采用烯丙基缩水甘油醚活化法,并对琼脂糖微球基质的活化和配基偶联条件进行了优化,优化后活化密度达260 μmol·ml^-1以上,配基密度达120 μmol·ml^-1。同时以抗体和蛋白A的混合物为研究对象来考察该介质对抗体中蛋白A的清除能力,结果表明对蛋白A的有效去除率达到83.1%,为抗体制品中蛋白A的清除提供了一种可行性方法。     

微流芯片制备粒径均一的壳聚糖-NaCS/TPP微胶囊

以壳聚糖、纤维素硫酸钠（NaCS）和三聚磷酸钠（TPP）为原料,采用十字型微流芯片制备了粒径均一的壳聚糖-NaCS/TPP微胶囊,微通道宽200 μm,高1 mm。分析了微通道内的三种流动状态、分散剂用量、壳聚糖浓度、油水两相流速等因素对壳聚糖微液滴形成的影响,确定了合适的制备条件。以2%(质量)壳聚糖醋酸水溶液为水相,液体石蜡为油相,5%(质量)Span 85为油相分散剂,水相流速5 μl·min^-1,调节油相/水相流速比为40～100,可以形成均匀的壳聚糖微液滴,粒径分布系数小于0.1。壳聚糖微液滴与1% NaCS和3% TPP的混合溶液反应,固化形成了中间空心、周边由两层膜构成的壳聚糖-NaCS/TPP微胶囊。结果表明,采用微流芯片可以有效控制液滴直径,制备粒径均一的微胶囊。     

新型混合模式层析介质制备及用于牛初乳免疫球蛋白分离

针对免疫球蛋白的分离纯化,设计和制备了以2-巯基咪唑为功能配基的新型混合模式层析介质B-DVS-MI,兼有疏水、静电和亲硫作用。采用二乙烯基砜活化法,优化了琼脂糖微球基质的活化反应和配基偶联条件,活化密度达100 μmol·ml-1以上,2-巯基咪唑配基密度达65 μmol·ml-1。将该介质用于从牛初乳蛋白粉中分离免疫球蛋白,考察了B-DVS-MI对牛初乳免疫球蛋白的静态和动态吸附性能,结果表明介质吸附容量达到127.6 mg·(g介质)-1,具有非盐依赖的吸附特性,且pH显著影响吸附性能,通过调节pH可实现高效吸附和洗脱。确定了合适的层析分离条件,从牛初乳蛋白粉中直接分离牛初乳免疫球蛋白,纯度达95%以上。结果充分说明,制备的新型混合模式层析介质B-DVS-MI是一种高效分离免疫球蛋白的分离介质。     

微通道内双重孔结构SiO2微球的制备

利用微流控技术制备双重孔结构SiO₂微球具有微观结构和宏观形貌可控的优点。在同轴环管微通道中,通过pH和温度变化引发快速凝胶过程制备得到了具有双重孔结构的SiO₂微球,考察了有机相溶剂性质、有机相流速以及凝胶温度等因素对微球宏观形貌以及微观结构的影响规律。实验结果表明,制备得到的SiO₂微球粒径在300～600 μm可调,比表面积可以达到1000 m²·g^-1,介孔孔径在4～10 nm之间,大孔孔径在400～1500 nm之间。实验发现有机相流速的增大会导致微球粒径的减小,提高三辛胺对盐酸的萃取速率,加快二氧化硅溶胶粒子的凝胶过程,更易生成松散的网状大孔结构。较高的凝胶温度会增大SiO₂微球介孔的孔容和孔径。     

乙二胺丙酰化交联壳聚糖微球对甲基橙的吸附性能

通过丙烯酰化交联壳聚糖微球（AGCS）上的丙烯酰基团与乙二胺的Michael加成反应，制备乙二胺丙酰化交联壳聚糖微球（EAGCS）。分别采用傅里叶变换红外光谱（FT-IR）、X射线光电子能谱（XPS）和X射线衍射（XRD）表征了EAGCS的结构，利用激光粒度分析仪进行了粒径分布分析，考察了甲基橙（MO）溶液pH、温度、浓度和EAGCS用量对EAGCS吸附性能的影响。结果表明：EAGCS为球形，微球的体积平均粒径为57.4 μm，粒径分布系数1.53；在最佳条件下，EAGCS的吸附去除率为99.6%，吸附容量可达545.40 mg·g^-1，吸附过程属于自发放热过程，吸附动力学符合二级动力学，吸附过程可采用Langmuir和Freundlich等温吸附模型来描述。     

模板沉积法制备大孔高比表面积Fe3O4/P(GMA-co-EGDMA)磁性复合微球

介绍了一种以大孔高比表面积甲基丙烯酸缩水甘油酯（GMA）与二甲基丙烯酸乙二醇酯（EGDMA）共聚交联微球［P(GMA-co-EGDMA)］为模板制备磁性复合微球的简单方法。制备过程包括Fe³⁺和Fe²⁺的浸入、OH^-作用下孔内铁离子的共沉淀两步。在此过程中考察了浸泡温度、浸泡时间、共沉淀温度以及沉积次数对微球磁含量的影响,确定最佳制备工艺为50℃浸泡4 h,70℃反应1 h,如此反复4次磁含量可以达到45.24%。并通过SEM、VSM、XRD、TGA及压汞仪、激光粒度仪等手段对Fe₃O₄/P(GMA-co-EGDMA)的形貌、比饱和磁化强度、磁含量及孔性能进行了表征,微球的粒径范围处于100～200 μm之间,平均粒径为162 μm,比饱和磁化强度为10.92 emu·g^-1,平均孔径及比表面积分别为60 nm和116 m2·g^-1。     

纳米腐殖酸基离子交换复合树脂动态吸附-脱附冶金镍镉废水

系统研究了纳米腐殖酸基离子交换复合树脂在多离子共存体系中对Ni²⁺/Cd²⁺的选择吸附性能。以此为基础,通过多柱串联、饱和吸附、洗脱液套用方法完成了对Ni²⁺、Cd²⁺冶金废水资源化治理研究,用扫描电镜(SEM)、红外光谱仪(FTIR)、热重分析仪(TG-DTA)、X射线光电子能谱仪(XPS)及N₂吸附-脱附分析仪(BET)等物理手段对复合树脂的微观形貌、化学结构、耐热性、元素组分变化及孔径分布进行表征。研究结果表明:纳米腐殖酸基复合树脂对Ni²⁺、Cd²⁺离子具有吸附速度快[0.55～1.50 mg·(g·min)^-1]、交换容量高(Ca²⁺、Mg²⁺共存体系中对Ni²⁺、Cd²⁺吸附容量分别为139 mg·g^-1和148 mg·g^-1)、选择性能好等优点,回收溶液中镍和镉离子浓度和纯度高(分别为45.15 g·L^-1和 39.17g·L^-1,且C_Ni(Ⅱ)/C_total 0.989,C_Cd(Ⅱ)/C_total 0.994);吸附-洗脱200次后,其物理、化学结构性能稳定;断面形貌变化不明显,交换容量基本不变,可重复使用;比表面积、平均孔径及孔容分别为1189.85 m²·g^-1、30.2 nm 和0.96 cm³·g^-1,热稳定性能好;氮含量从16%降至12%、氧含量由26.49%升至29.96%,交换容量由5.38mmol·g^-1升至6.06 mmol·g^-1。     

双重Pickering乳液法制备聚丙烯酰胺多孔微球及应用

采用亲水性气相二氧化硅N20和疏水性气相二氧化硅H30复配表面活性剂制备O/W/O型双重乳液,以此为模板,聚合中间相,挥发内相制备聚丙烯酰胺(PAM)多孔微球,并用于染料分子亚甲基蓝的吸附。结果表明：乳液显微镜照片显示水油比对双重乳液的形成有很大的影响,当水油比(O₁/W)/O₂为(1/2)/2时,可得到稳定的双重乳液;扫描电镜(SEM)照片显示PAM多孔微球基本呈球形,但粒径不均匀,球体表面粗糙,内部为空心结构;激光粒度仪(DLS)结果表明PAM微球平均粒径为356nm,多分散系数(PDI)为0.718,比表面积为230m²/g,粒径分布宽;在吸附温度35℃、吸附时间5min时对亚甲基蓝的吸附率为98.89%,最大吸附率超过99%,在吸附速率和吸附率上均优于传统PAM吸附剂,本研究为染料废水的处理提供了新方法。     

水热法制备TiO2片晶及光催化性能

以稳定的金红石相TiO₂为原料,水热法制备出微米级TiO₂片晶。采用扫描电镜（SEM）、X射线粉末衍射（XRD）、N₂吸附-脱附等分析手段对样品进行了分析。将不同温度下煅烧后样品进行甲基橙降解实验。实验结果表明,反应48 h可获得长60～80μm、宽30～60μm、厚4～9 μm的介孔片晶。经450℃煅烧可得到锐钛矿相占83.6%的混晶,比表面和孔径分别为68 m²·g^-1、21.6 nm,对甲基橙降解率最高,在30 min内降解了92.4%,60 min几乎全部降解,其催化活性优于商用P25,且微米级的颗粒更容易回收再利用。     

Preparation of cellulose–tungsten carbide composite beads with ionic liquid for expanded bed application

Expanded bed adsorption (EBA) is an integrated technology for capturing target biomolecules directly from unclarified feedstock. The adsorbents should be designed specially to ensure the perfect performance of the expanded bed. In this study, an ionic liquid (IL), 1‐butyl‐3‐methylimidazolium chloride, was used to dissolve cellulose directly to prepare cellulose–tungsten carbide composite beads with water‐in‐oil suspension and cooling/ethanol regeneration. The preparation conditions were optimized, especially for four key factors, the cellulose concentration, ratio of the oil phase to the cellulose solution, stirring speed, and addition of tungsten carbide powder. The results showed that the tungsten carbide powder emerged well in the cellulose matrix as an inert densifier. The composite beads had a spherical appearance, a suitable size and size distribution, an appropriate wet density of 1.32–1.68 g/mL, a porosity of 90–96%, a pore radius of 45–65 nm, and a specific surface area of 30–42 m²/mL. These results show the potential application for this EBA process. Compared to the traditional technology with cellulose xanthate viscose, the new method with the IL as the nonderivatizing dissolution solvent is technically feasible, has concise processing, and is environmentally friendly. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Improvement of water quality using alginate/montmorillonite composite beads

The aim of this study is to explore naturally occurring sorbents that have high affinity for heavy metal treatment. In this respect, series of polymer‐clay composite beads that consists of Na‐alginate and montmorillonite clay were prepared using CaCl₂ as crosslinker. The prepared composite bead was characterized by scanning electron microscope (SEM). Removal of lead from aqueous solution using this bead was then studied in batch adsorption experiments. The amount of lead removed was found to increase as the percent of Na‐alginate increase in the composite beads. The experimental results also showed that the equilibrium contact time was obtained within ∼ 100 min with (t_1/2) of 50% adsorption in less than 10 min. Lead adsorption was found to be strongly pH‐dependent and display a maximum uptake capacity (244.6 mg/g) at pH 6 and minimum uptake (76.6 mg/g) at pH 1. Maximum lead adsorption was found to increase with increasing initial lead concentration in the feed solution and with decreasing temperature of experiment. Based on alginate‐montmorillonite beads packed columns, a highly efficient method for Pb(II) removal from aqueous solution was developed. The effect of flow rate on adsorption of 100 mg/L Pb(II) in the packed‐bed column was investigated by changing the flow rate between 0.5 and 2.5 mL min⁻¹. The recovery of 100 mg/L Pb(II) in the packed‐bed column was found to be 100% at flow rates 0.5 and 1 mL min⁻¹ then lowered to be 93% and 84% at flow rates 1.5 and 2.5 mL min⁻¹, respectively. The effect of Pb(II) flow concentration ranging from 10 to 1000 mg/L on the adsorption of lead ions at constant flow rate 1.0 mL min⁻¹ was also studied using column procedure. Technical feasibility for the uses of the prepared composite beads for the treatment of actual polluted wastewater samples collected from some industrial cities in Egypt was investigated. The evaluation of the system was performed by a complete analysis of heavy metals in the wastewater samples before and after the treatment process. The results showed a promising possibility for producing wastewater of better quality using such prepared beads. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Emulsion gel beads prepared by sedimentation polymerization using two-fluid atomization and their Pd(II) ion adsorption properties

An emulsion gel adsorbent which was a polymeric hydrogel containing randomly distributed oil microdroplets of an extractant was developed for improved metal adsorption in our previous study. This study focuses on the preparation of monodisperse, millimeter- or sub-millimeter-sized emulsion gel beads, for which a novel production method combining sedimentation polymerization and two-fluid atomization is proposed. The method involves the drop-wise addition of a pre-gel oil-in-water emulsion solution into a silicone oil through a nozzle, with nitrogen gas flow, and the subsequent free-radical polymerization of the pre-gel droplets during their descent. A novel type of emulsion gel bead composed of a poly(ethylene glycol) methyl ether acrylate hydrogel and di-n-hexylsulfide as an extractant was developed. The size of the emulsion gel beads was controlled by adjusting the gas flow rate. The emulsion gel beads successfully adsorbed Pd(II) ions that were used as a model metal.     

Size controlling of monodisperse carboxymethyl cellulose microparticles via a microfluidic process

Monodisperse carboxymethyl cellulose containing phenolic groups (CMC‐Ph) microdroplets with a radius of 100–400 μm and a coefficient of variation below 3% were produced in a coflowing microfluidic device. The CMC‐Ph solution containing horseradish peroxidase was used as the disperse phase and liquid paraffin containing H₂O₂ and lecithin as the continuous phase. The size of microdroplets decreased with the decreasing diameter of the inner channel and concentration of the disperse phase. When using a 0.04% CMC‐Ph solution and the device with the inner diameter of 160 μm, the size of the microdroplets can be further controlled by the flow rates of both the continuous phase and disperse phase following exponential models. The volume of the microdroplet was not inversely proportional to the flow‐rate ratio of the continuous phase to the disperse phase. There was a weak dependence of the volume on the flow of the continuous phase. The monodisperse microparticles possessed potential application for sensor, drug delivery system, cell encapsulation, catalysis, and imaging. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40663.     

Development of a fixed‐bed column with cellulose/chitin beads to remove heavy‐metal ions

Environmental friendly cellulose/chitin beads, having relatively high mechanical properties, were successfully prepared from a blend of cellulose and chitin in 6 wt % NaOH/5 wt % thiourea aqueous solution by coagulating with 5% H₂SO₄ aqueous solution. The ability of the beads to adsorb Pb²⁺ in an aqueous solution was measured with a fixed‐bed column. The effects of important parameters, to design an adsorption column of the cellulose/chitin beads for fixed‐bed columns, were investigated. The breakthrough curves for the adsorption behavior indicated that the column performance was improved with decreasing initial lead concentration, ionic strength, flow velocity or bead size, as well as increasing pH dependence and bed height. Column studies showed that constants, calculated from the experimental data, and the Bed Depth Service Time (BDST) model had a good correlation. The columns were easily regenerated by treating with 0.1 mol/L HCl aqueous solution after the adsorption of metals, providing a simple and economical method for removal and recovery of heavy metals. After four adsorption–desorption cycles, the efficiency of column for the removal of lead was not significantly reduced (not more than 5%). It is shown that heavy‐metal biosorption processes in fixed‐bed columns could give a broad range of potential industrial applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 684–691, 2004     

程序降温反相悬浮技术制备球形纤维素珠体

以纤维素/N-甲基吗啉-N-氧化物(NMMO)/H2O溶液为原料,用NMMO法,通过程序降温反相悬浮技术制备出球形纤维素珠体,并进行制备工艺的优化实验和纤维素珠体的性能检测。实验结果表明,以10#变压器油为分散相,油水体积比V(油)∶V(水)=4∶1,m(复合型分散剂L-1)∶m(纤维素/NMMO/H2O溶液)=15∶100,在300r/m in的搅拌速度,可制备出粒径分布均匀的球形纤维素珠体,此时均一系数K=1.216。所制备的纤维素珠体的w(H2O)=74.0%,比表面积为215.6 m2/g,孔度为81.2%,湿视密度为0.63 g/mL,湿真密度为1.21 g/mL。在酸浓度或碱浓度为0.1~6.0 mol/L,随着酸浓度或碱浓度的增高,纤维素珠体的质量损失率递增,分别为0.1%~12.4%和0.8%~28.8%。     

EGDE交联的载镧壳聚糖微球对氟离子的静态和动态吸附

利用乙二醇二缩水甘油醚(EGDE)替代戊二醛对壳聚糖微球进行交联,然后负载稀土镧离子La(Ⅲ),制备得到新型的除氟剂(CEB-La).研究了CEB-La对F-的静态和动态吸附性能.静态吸附实验结果表明:该除氟剂的静态吸附条件为pH7.0、温度50℃、吸附时间60 min、振荡频率120 r·min-1;当CEB-La用...     

NMMO法球形纤维素珠体的制备及粒径分布的研究

以N-甲基吗啉-N-氧化物(NMMO)和马尾松漂白硫酸盐浆为原料,制备出纤维素/NMMO/H2O溶液,并以纤维素/NMMO/H2O溶液为原料,采用程序降温反相悬浮技术制备球形纤维素珠体,通过单因素实验和正交实验确定成球优化条件为:纤维素/NMMO/H2O溶液的纤维素质量分数为8.0%,含水率为15.8%,以变压器油为分散相,油∶溶液(V/V)=4∶1,Span80作为分散剂,用量为纤维素/NMMO/H2O溶液的1.5%,搅拌速度为300 r/min。在上述条件下可制得粒径分布在0.45～0.20 mm占70.0%以上的球形纤维素珠体。     

Pd(II) ion adsorption onto emulsion gel beads in a fixed bed

We developed previously an emulsion gel adsorbent for improved metal adsorption. This study focuses on a continuous adsorption–desorption process of metal ions from a solution onto emulsion gel beads using the fixed-bed method. The monodisperse millimeter-sized emulsion gel beads, a polymeric hydrogel containing randomly distributed oil microdroplets of di-n-hexylsulfide as an extractant, were prepared using an automatic production method combining sedimentation polymerization and two-fluid atomization. The isotherms and the kinetics for Pd(II) adsorption were investigated. A continuous adsorption–desorption process was successfully demonstrated, and the breakthrough curve was successfully predicted by a mathematical analysis.