Co-reporter:Jia Gao, Xiaoxu Wang, Jianshu Zhang, Ruili Guo
Separation and Purification Technology 2016 Volume 159() pp:116-123
Publication Date(Web):8 February 2016
DOI:10.1016/j.seppur.2016.01.005
•The solvent-resistant PAN/SiO2 hybrid hollow fiber membranes were prepared.•SiO2 were introduced to manipulate the structure of membrane.•Heat-treated hybrid membranes showed satisfied acetylene absorption performance.The heat-treated PAN/SiO2 hybrid membranes were prepared through combining organic/inorganic blend and heat treatment methods for acetylene absorption process. The effect of SiO2 contents (0.5, 1, 2 and 3 wt%), heat treatment temperature on the membrane morphology, structure and performance were investigated. The as-prepared membranes were characterized by FTIR, SEM, gas permeation test, hydrophobicity and mechanical stability. The results showed that the hybrid membranes had higher gas permeation properties due to their high pore sizes, porosities and thin skin layer. The membranes were further investigated as a membrane contactor for acetylene absorption using 1-methyl-2-pyrrolidinone (NMP) as absorbent. The acetylene absorption performance increased with increasing SiO2 loading, and the acetylene mass transfer flux and absorption efficiency of the hybrid membrane contain 1 wt% SiO2 were about 101% and 107% higher than the plain membrane at the same operating conditions, respectively.
Co-reporter:Yun Qin, Jianfei Lv, Xin Fu, Ruili Guo, Xueqin Li, Jianshu Zhang and Zhong Wei
RSC Advances 2016 vol. 6(Issue 3) pp:2252-2258
Publication Date(Web):22 Dec 2015
DOI:10.1039/C5RA25089G
Three types of amino acid salts (sodium lysine, sodium arginine, sodium histidine) were introduced into SPEEK polymer matrix to fabricate a series of SPEEK/amino acid salt membranes for CO2 separation. The membranes could efficiently separate CO2 from a CO2/CH4 mixture due to the simultaneous improvement of CO2 permeability and separation performance. Firstly, the amino acid salt contained a larger number of amino groups (–NH2), which could reversibly react with CO2, improving the CO2 molecules transfer performance. Secondly, the ether oxygen structure (–O–) in the polymer chain and the carboxyl groups (–COO−) in the amino acid salt had an excellent affinity for CO2, enhancing the solubility selectivity. Thirdly, the introduction of amino acid salt increased the water uptake, and water was favored over CO2 dissolution; this was also good for the increase of solubility selectivity. Among the three types of amino acid salts, the membrane doped with 20 wt% sodium lysine (SPEEK/LLS-20) showed the highest CO2 permeability of 295.6 barrer and CO2/CH4 selectivity of 71.8 at 2 bar and room temperature, surpassing the 2008 Robeson upper bound line.
Co-reporter:Jianfei Lv;Yuanyuan Liu;Yun Qin;Jianshu Zhang ;Zhong Wei
Journal of Applied Polymer Science 2016 Volume 133( Issue 19) pp:
Publication Date(Web):
DOI:10.1002/app.43399
ABSTRACT
SPEEK/phosphate salts membranes were prepared and utilized for CO2/CH4 separation. SPEEK with abundant –SO3H groups and EO groups on polymer chains would be beneficial for CO2 transport. The doped phosphate salts (NaH2PO4, Na2HPO4 and Na3PO4) with different acid-base properties increased the water content in the membrane, and water was expected to increase both the solubility and diffusivity of CO2 in the membrane. All membranes were characterized by FTIR, TGA, and XRD. The CO2 permeability and CO2/CH4 selectivity of SPEEK/Na3PO4 membranes were higher than that of SPEEK/NaH2PO4 and SPEEK/Na2HPO4 membranes. Compared to the pure SPEEK membrane, the CO2 permeability and CO2/CH4 selectivity of SPEEK/Na3PO4−10 membrane were increased by 144% and 65%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43399.
Co-reporter:Xiaoxu Wang;Jia Gao;Jianshu Zhang;Xiaopeng Zhang
Chemical Engineering & Technology 2015 Volume 38( Issue 2) pp:215-222
Publication Date(Web):
DOI:10.1002/ceat.201400338
Abstract
The separation of acetylene from a gas mixture was investigated using a polytetrafluoroethylene hollow-fiber membrane contactor and 1-methyl-2-pyrrolidinone as absorbent. The effects of the gas velocity, the liquid velocity, the feed gas concentration, and the module length on the acetylene mass transfer were investigated. The results showed that the acetylene mass transfer flux increased with increasing liquid velocity, gas velocity, and feed gas concentration, but decreased with increasing membrane module length. A mathematical model was used to predict the wetting extent of the membrane and the mass transfer resistance in the acetylene mass transfer process. The wetting extent of the membrane was found to increase with increasing liquid velocity and to be effectively restrained with increasing gas velocity. The liquid phase resistance and the wetted-membrane phase resistance controlled the acetylene mass transfer in the acetylene absorption process. The acetylene absorption efficiency was maintained at 90 % for 114 h of the C2H2 membrane absorption–thermal desorption cycle process.
Co-reporter:Xueqin Li, Ruili Guo, Xiaopeng Zhang, Xiaoyue Li
Separation and Purification Technology 2012 Volume 88() pp:146-150
Publication Date(Web):22 March 2012
DOI:10.1016/j.seppur.2011.12.018
The present study aims to extract bioactive glabridin from licorice extract using imidazolium-based ionic liquids (ILs). A series of 1-alkyl-3-methylimidazolium ionic liquids with different anions and alkyl chain lengths of cations were selected to extract glabridin. The results are as follows: IL anions have a significant effect on the extraction efficiency of glabridin, the alkyl chain length of imidazolium cations has a minor effect on the extraction efficiency of glabridin, and IL with [NTf2]− anion and [C6mim]+ cation achieve better performances. Under optimal conditions of glabridin extraction technology, a glabridin distribution ratio of 72.67 was achieved with [C6mim][NTf2]. The results show that during the extraction, the interactions between IL and glabridin were mainly based on hydrogen-bonding interactions and the hydrophobic interactions.Highlights► Ionic liquids with different anions and alkyl chain lengths of cations were screened. ► A glabridin distribution ratio of 72.67 was achieved with [C6mim][NTf2]. ► The extraction of glabridin was greatly affected by ionic liquid anions. ► The interactions mainly based on hydrogen-bonding and the hydrophobic interactions.
