CO2在水作载体的微孔膜内的促进传递

Ｉｎｒｅｃｅｎｔｙｅａｒｓ ,ｔｈｅｆｉｘｅｄｃａｒｒｉｅｒｍｅｍｂｒａｎｅｓｆｏｒＣＯ2 ,ｅｓｐｅｃｉａｌｌｙｔｈｅｍｅｍｂｒａｎｅｓｈａｖｉｎｇａｍｉｎｅｍｏｉｅｔｙ[1— 3] ｈａｖｅｂｅｅｎｉｎｖｅｓｔｉｇａｔｅｄｅｘｔｅｎｓｉｖｅｌｙ .Ｍａｔｓｕｙａｍａｅｔａｌ[4 ] ｆｏｕｎｄｔｈｅｐｅｒｆｏｒｍａｎｃｅｏｆｗａｔｅｒ -ｃｏｎｔａｉｎｉｎｇｍｅｍｂｒａｎｅｓｗａｓｂｅｔｔｅｒｔｈａｎｔｈａｔｏｆｄｒｙｍｅｍｂｒａｎｅｓ .Ｔｈｅｓｅｌｅｃｔｉｖｉｙｏｆｔｈｅｃｏｎｔａｉｎｉｎｇｗａｔｅｒｍｅｍｂ…     

CO2固定载体膜过程中物质间相互作用及其影响

采用自由基聚合合成了聚乙烯基吡咯烷酮，经水解得到了聚N-乙烯基-γ氨基丁酸钠(PVSA).该聚合物含有能与CO₂进行可逆反应的仲胺基和羧基.以PVSA为表层，以微孔膜为支撑体，制备了新型CO₂固定载体复合膜.以CO₂/CH₄体系为分离对象，研究了CO₂、CH₄、PVSA、水、膜中小分子杂质和支撑膜等相互之间的作用，同时探讨了这些相互作用对膜结构和性能的影响.     

用PVP水解物制备CO2固载膜及膜的性能

以自由基聚合合成了聚乙烯基吡咯烷酮（PVP），并用其水解产物聚N-乙烯基-γ-氨基丁酸钠（PVSA）和聚砜（PS）超滤膜制备了PVSA/PS复合膜；用红外光谱、X射线衍射等方法研究了PVP及其水解产物PVSA的结构，证实了PVSA含有可作为CO₂载体的仲胺基与羧基；测试了复合膜的透气性能及对CO₂/CH₄的选择性.结果表明，在26℃，压力为1333Pa时，CO₂渗透速率可达5.46×10^-7 cm³(STP)•cm^-2•s^-1•Pa^-1，CO₂/CH₄的理想分离因子达到212.1.随着进料气压力的增大，CO₂/CH₄的分离因子及CO₂的渗透速率均呈下降趋势.依据膜的渗透通量随压力的变化特性以及不同状态下膜的红外光谱，分析了膜对CO₂的促进传递机理.     

CO2通过合成聚合物膜的促进传递

Two kinds of fixed carrier membrane materials containing secondary amine and carboxyl groups whichcan be used as carriers of CO2 were prepared. One was poly(N-vinyl-γ-sodium aminobutyrate)(PVSA), whichwas obtained through the hydrolysis of polyvinylpyrrolidone (PVP) synthesized with N-vinylpyrrolidone(NVP) byradical polymerization. The other was poly(N-vinyl-γ-sodium aminobutyrate-co-sodium acrylate)(VSA-SA), whichwas obtained through the hydrolysis of copolymer of N-vinylpyrrolidone and acrylamide(AAm) (NVP-AAm). Thecomposite membranes were developed with PVSA or VSA-SA as active layer and polysulfone (PS) as supportmembranes. The permeation rates of pure CO2 and CH4 gas as well as binary mixtures of CO2/CH4 throughthe composite membranes were measured. The results show that the composite membranes present better CO2permeation rates than other fixed carrier membranes do reported in literature. For example, at 26℃, 1330 Pa of CO2pressure, the PVSA/PS composite membrane displays a CO2 permeation rate of 5.95 × 10-7 cm3.cm-2.s-1.pa-1with CO2/CH4 ideal separation factor of 212.1. At 20℃, 6400Pa of CO2 pressure, the VSA-SA/PS compositemembrane displays a CO2 permeation rate of 4.24 × 10-8 cm3@cm-2.s-1.Pa-1 with CO2/CH4 ideal separationfactor of 429.7. The results with the gas mixtures are not as good as those obtained with pure gas because ofthe coupling effects between CO2 and CH4. The heat cross-linked membrane shows good separation factor due todensification of the polymer.     

高富氧载体促进输送膜的研究

基于献，对高富氧载体促进输送膜的载体特征，基膜结构，输氧机理，富氧性能与寿命，富氧工艺设计及经济分析进行了评述。讨论了富氧性能对载体含量，溶剂，温度和压力等的依赖性。指出最高的透氧系数和氧氮分离系数分别达１．１１×１０＾－７ｃｍ＾３（ＳＴＰ）．ｃｍ／ｃｍ＾２．ｓ．ｃｍＨｇ和８０．０。用该膜进行一级空气分离可获得氧含量９０％和氧流量为１．０６×１０＾－３ｃｍ＾３（ＳＴＰ）／ｓ．ｃｍ＾２的富氧空气，     

COMPETITIVE FACILITATED TRANSPORT OF ACID GASES IN MODIFIED CARRIER MEMBRANES

1 INTRODUCTIONMany attempts to develop semipermeable membranes for gas separation have beendone over the past twenty years [1,2].However,it is still difficult to prepare apolymer film which makes certain gas separation processed within range of being econ-omically and technically feasible,since most polymeric materials are relativelyimpermeable to gases.Facilitated transport concept which was first proposed by     

CO2固定载体膜过程中物质间相互作用及其影响

采用自由基聚合合成了聚乙烯基吡咯烷酮 ,经水解得到了聚N 乙烯基 γ氨基丁酸钠 (PVSA) .该聚合物含有能与CO2 进行可逆反应的仲胺基和羧基 .以PVSA为表层 ,以微孔膜为支撑体 ,制备了新型CO2 固定载体复合膜 .以CO2 /CH4体系为分离对象 ,研究了CO2 、CH4、PVSA、水、膜中小分子杂质和支撑膜等相互之间的作用 ,同时探讨了这些相互作用对膜结构和性能的影响     

促进传递液膜分离丙烯(Ⅰ)工艺条件

用含有AgNO3载体的支撑液膜对丙烯进行促进传质分离,研究了不同工艺条件、支撑体材料等因素对丙烯纯度、渗透速率、单程收率及选择性因子的影响．在最佳条件下,丙烯的纯度达99.3％～99.7％,单程收率5.6％,选择性因子＞700．给出了液膜稳定性处理方法．实践证明,支撑液膜促进传递过程明显优于被动的溶解-扩散过程．     

PVAm/PAN复合膜的制备及其对CO2/CH4的分离性能

New polymeric membrane materials——polyvinyl amine (PVAm) with different primary amine contents were synthesized.By covering polyacrylonitrile(PAN) ultrafiltration membranes with PVAm, the PVAm/PAN composite membranes for CO₂/CH₄ separation were prepared. The composite membranes containing more primary amino groups have higher selectivity for CO₂/CH₄.The cross-linking of acid or glutaradehyde could improve the gas permselectivity of the composite membranes. With decreasing CO₂ content in the feed gas, the CO₂/CH₄ separation factor increased.When the feed gas was 25%(vol) CO₂ and 75%(vol) CH₄, the CO₂ permeation rate was 4.1×10^-9cm³(STP) •cm^-2•Pa^-1•s^-1, and the CO₂/CH₄ separation factor was 180.     

用PVP水解物制备CO2固载膜及膜的性能

以自由基聚合合成了聚乙烯基吡咯烷酮 (PVP) ,并用其水解产物聚N 乙烯基 γ 氨基丁酸钠 (PVSA)和聚砜 (PS)超滤膜制备了PVSA/PS复合膜 ;用红外光谱、X射线衍射等方法研究了PVP及其水解产物PVSA的结构 ,证实了PVSA含有可作为CO2 载体的仲胺基与羧基 ;测试了复合膜的透气性能及对CO2 /CH4的选择性 .结果表明 ,在 2 6℃ ,压力为 1333Pa时 ,CO2 渗透速率可达 5 4 6× 10 -7cm3 (STP)·cm-2 ·s-1·Pa-1,CO2 /CH4的理想分离因子达到 2 12 1.随着进料气压力的增大 ,CO2 /CH4的分离因子及CO2 的渗透速率均呈下降趋势 .依据膜的渗透通量随压力的变化特性以及不同状态下膜的红外光谱 ,分析了膜对CO2 的促进传递机理     

CO2通过合成聚合物膜的促进传递

Two kinds of fixed carrier membrane materials containing secondary amine and carboxyl groups which can be used as carriers of CO2 were prepared. One was poly(N-vinyl-7-sodium aminobutyrate)(PVSA), which was obtained through the hydrolysis of polyvinylpyrrolidone (PVP) synthesized with N-vinylpyrrolidone(NVP) by radical polymerization. The other was poly(N-vinyl-7-sodium aminobutyrate-co-sodium acrylate)(VSA-SA), which was obtained through the hydrolysis of copolymer of N-vinylpyrrolidone and acrylamide(AAm) (NVP-AAm). The composite membranes were developed with PVSA or VSA-SA as active layer and polysulfone (PS) as support membranes. The permeation rates of pure CO2 and CH4 gas as well as binary mixtures of CO2/CH4 through the composite membranes were measured. The results show that the composite membranes present better CO2 permeation rates than other fixed carrier membranes do reported in literature. For example, at 26℃, 1330 Pa of CO2 pressure, the PVSA/PS composite membrane displays a CO2 permeation     

超临界CO2中合成聚碳酸酯

在超临界CO₂介质中由双酚A（BPA）和碳酸二苯酯（DPC）合成了双酚A型聚碳酸酯（PC）。反应生成的苯酚能够溶解扩散到超临界流体中。用红外光谱（FT-IR）、核磁共振谱（¹H-NMR）表征了产物的结构。凝胶渗透色谱（GPC）测试表明，合成过程中存在线形缩聚和成环两种不同的反应机理，产物的重均分子量高达117740，分子量分布指数P_d=1.33;差示扫描量热法（DSC）测试表明，超临界CO₂能增塑PC致使其玻璃化转变温度（T_g）降低。考察了反应时间、搅拌转速、反应温度等因素对PC分子量的影响。在反应压力为10 MPa下较佳反应时间为50 h，较佳搅拌转速为800 r·min^-1，较佳反应温度为120℃。     

新型燃烧方式下SO2脱除机理

对O₂/CO₂燃烧方式下SO₂的脱除机理进行了研究.静态实验和动态实验结果表明这种新型燃烧方式有利于降低SO₂的排放,SO₂脱除存在均相脱硫和多相脱硫的协同作用;新型燃烧方式下高CO₂浓度导致燃烧气氛中化学成分不同于传统的空气气氛,SO₂与燃烧气氛中存在的其他组分反应,生成硫的不同形态产物,SO₂只是其中的一种产物形态,导致SO₂总量排放减少;同时 O₂/CO₂燃烧气氛使燃煤中硫的氧化程度减弱;燃煤中本身所含脱硫剂存在优化的微观结构,该种结构有利于脱硫和对底灰中硫的吸附,也导致SO₂的排放量降低;CHEMKIN动力学计算结果进一步表征了以上机理.     

Novel fixed‐carrier membranes for CO2 separation

A new membrane material having two kinds of CO₂ carriers was obtained. Composite membranes were prepared with the material and support membranes. The facilitated transport of CO₂ through these membranes was performed with pure CH₄ and CO₂ as well as CH₄/CO₂ mixtures containing 50 vol % CO₂. The results show that the membranes possess better CO₂ permeance than that of other fixed carrier membranes reported in the literature. In the measurements with pure gases, at 26°C, 0.013 atm of CO₂ pressure, the membrane with polysulfone support displays a CO₂ permeance of 7.93 × 10^?4 cm³ /cm² s cmHg and CO₂/CH₄ ideal selectivity of 212.1. In the measurements with mixed gases, at 26°C, 0.016 atm of CO₂ partial pressure, the membrane displays a CO₂ permeance of 1.69 × 10^?4 cm³ /cm² s cmHg and CO₂/CH₄ selectivity of 48.1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2222–2226, 2002     

PVAm/PAN复合膜的制备及其对CO2/CH4的分离性能

引　言天然气和沼气中含有的大量CO2 将直接影响这些气体的燃烧效果和以这些气体为原料的产品质量 ,并对管线及设备造成腐蚀 ;同时由于CO2 等气体导致的温室效应 ,正引起严重后果 ;再者 ,发展生物技术也对CO2 的分离提出要求 .因此 ,分离CO2 技术已成为目前世界膜界研究的重点[     

填料塔中碱性水溶液对空气中微量CO2的净化

在填料吸收塔中研究了NaOH水溶液(0.30～0.97 kmol·m^-3)以及有机胺水溶液(MEA：0.10～0.50 kmol·m^-3；DEA：0.10～0.50 kmol·m^-3)吸收空气中微量CO₂的过程，并建立了该过程的数学模型，用NaOH水溶液吸收空气中微量CO₂的实验结果估算了填料的有效相界面积a_v，并根据有效相界面积以及有机胺水溶液吸收CO₂的实验结果预测了MEA、DEA水溶液吸收空气中微量CO₂的总反应速率常数(k_ov)_exp.由实验结果计算得到的总反应速率常数与数学模型能很好地吻合.     

超临界CO2萃取丁香油的数值模拟

为了预测超临界CO₂萃取挥发油动态过程,根据挥发油在超临界CO₂与物料之间的质量传递平衡,采用集总参数法建立超临界CO₂萃取丁香油过程的数学模型。结合不同温度、压力、粒径和CO₂流速条件下的实验结果,对方程进行了合理的简化,并利用实验数据拟合出模型中CO₂密度、粒径和流速的系数。验证结果表明模型的计算值和实验值的平均相对误差在6. 88%～57. 78%之间,建立的数值模型能较好地描述实际的超临界CO₂萃取丁香油行为。     

甲基丙烯酸二甲氨基乙酯-丙烯腈共聚物膜的制备及其气体渗透性能

采用水溶液沉淀法合成了甲基丙烯酸二甲氨基乙酯（DM）和丙烯腈（AN）的共聚物,用红外光谱、黏度法和X射线衍射分析了聚合物的结构.实验考察了反应条件对共聚物结构的影响.在此基础上,通过溶液浇注法制备了甲基丙烯酸二甲氨基乙酯（DM）和丙烯腈（AN）的共聚物膜,研究了聚合物膜的CO₂、CH₄渗透性能.结果表明,由于共聚物中含有能与CO₂进行可逆反应的叔胺基,共聚物膜表现出较好的CO₂渗透性和CO₂/CH₄选择性,如在25℃、压力为1140 Pa时,CO₂的渗透速率可达 3.53×10^-12 cm³(STP)•cm^-2•s^-1•Pa^-1 , CO₂/CH₄ 的理想分离因子达到104.5.利用膜吸附CO₂和CH₄后红外光谱的变化,分析了膜对CO₂的促进传递机理.     

活性炭—二氧化氯法处理含酚饮用水的研究

本文采用活性炭－二氧化氯法,结合实例对含酚饮用水作了除酚研究,实验结果和工艺计算表明,活性炭和ＣｌＯ２均具有很好的除酚能力。Ｃ－ＣｌＯ２法比活性炭和ＣｌＯ２单独除酚具有投资少,成本低和水质高等优点,是处理含酚饮用水的一种较为理想的方法。     

Preparation of a Facilitated Transport Membrane Composed of Carboxymethyl Chitosan and Polyethylenimine for CO2/N2 Separation

The miscibility of carboxymethyl chitosan/polyethylenimine (CMCS/PEI) blends was analyzed by FT-IR, TGA and SEM. Defect-free CMCS/PEI blend membranes were prepared with polysulfone (PSf) ultrafiltration membranes as support layer for the separation of CO₂/N₂ mixtures. The results demonstrate that the CMCS/PEI blend is miscible, due to the hydrogen bonding interaction between the two targeted polymers. For the blended membrane without water, the permeability of CO₂ gas is 3.6 × 10⁻⁷ cm³ cm⁻² s⁻¹ cmHg⁻¹ and the corresponding separation factor for CO₂ and N₂ gas is about 33 at the pressure of 15.2 cmHg. Meanwhile, the blended membrane with water has the better permselectivity. The blended membrane containing water with PEI content of 30 wt% has the permeance of 6.3 × 10⁻⁴ cm³ cm⁻² s⁻¹ cmHg⁻¹ for CO₂ gas and a separation factor of 325 for CO₂/N₂ mixtures at the same feed pressure. This indicates that the CO₂ separation performance of the CMCS/PEI blend membrane is higher than that of other facilitated transport membranes reported for CO₂/N₂ mixture separation.