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1.
Summary The gas chromatographic behaviour of crosslinked macroporous 2-hydroxyethyl methacrylate grafted with 2-methyloxazoline was
investigated and the range of applicability of the copolymer was assessed. Retention index values were measured on this copolymer
and compared with those obtained on the terpolymer 2-hydroxyethyl methacrylate-ethylene dimethacrylate-acrylonitrile. Rohrschneider
constants and efficiency data for selected sorbates are given. The use of this type of polymer in the separation of various
types of compounds is documented by various examples. 相似文献
2.
3.
The principle of concentrating a substance from a mixture flow in a stationary sorbent layer of infinite length that was previously
developed for gas chromatography is extended to liquid chromatography.
Translated fromIzevestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1063–1065, May, 1997. 相似文献
4.
Na2CO3调质钙基脱硫剂硫化机理实验研究 总被引:7,自引:0,他引:7
对经Na2CO3溶液调质石灰石煅烧产物CaO的物理结构及硫化特性进行了研究,发现同等条件下调质后石灰石煅烧产物CaO(M-CaO)比未经调质的CaO(N-CaO)具有更高的钙转化率.利用XRD技术对CaO晶体结构进行了测定,通过比较二者的晶胞参数和晶格畸变度等并结合其孔特性,证实M-CaO之所以比N-CaO具有更高的钙转化率,是由于M-CaO比N-CaO具有更高的晶体缺陷浓度,使得在硫化反应过程中通过产物层的扩散具有更高的离子扩散率. 相似文献
5.
Brian H. Davison Nhuan P. Nghiem Gerald L. Richardson 《Applied biochemistry and biotechnology》2004,114(1-3):653-669
More than 25 sorbents were tested for uptake of succinic acid from aqueous solutions. The best resins were then tested for
successive loading and regeneration using hotwater. The key desired properties for an ideal sorbent are high capacity, complete
stable regenerability, and specificity for the product. The best resins have a stable capacity of about 0.06 g of succinic
acid/g of resin at moderate concentrations (1–5 g/L) of succinic acid. Several sorbents were tested more exhaustively for
uptake of succinic acid and for successive loading and regeneration using hot water. One resin, XUS 40285, has a good stable
isotherm capacity, prefers succinate over glucose, and has good capacities at both acidic and neutral pH. Succinic acid was
removed from simulated media containing salts, succinic acid, acetic acid, and sugar using a packed column of sorbent resin,
XUS 40285. The fermentation byproduct, acetate, was completely separated from succinate. A simple hot water regeneration successfully
concentrated succinate from 10 g/L (inlet) to 40–110 g/L in the effluent. If successful, this would lower separation costs
by reducing the need for chemicals for the initial purification step. Despie promising initial results of good capacity (0.06
g of succinic/g of sorbent), 70% recovery using hot water, and a recovered concentration of >100 g/L, this regeneration was
not stable over 10 cycles in the column. Alternative regeneration schemes using acid and base were examined. Two (XUS 40285
and XFS-40422) showed both good stable capacities for succinic acid over 10 cycles and >95% recovery in a batch operation
using a modified extraction procedure combining acid and hot water washes. These resins showed comparable results with actual
broth. 相似文献
6.
Urea can be sorbed by coordination (or complexation)with transitional metalpolyacrylic acid complex and transitional metal-polyacrylamide containing polyethylenepolyamine ligand complexes. The experimental results indicate that the sorbents can sorb about 60mg urea per gram of sorbent at 37℃ and the concentration of urea was 1300.0rag/1 in NaH_2PO_4 and Na_2HPO_4 buffer solution (pH=7.0) and the urea sorption capacity was affected by many factors such as other competive ligands, sorption time, pH and the concentration of urea. 相似文献
7.
Feng Liu Si Guo Yuan Xiao Li Wang A.E Polikarpov A.A. Shunkevich 《中国化学快报》2007,18(5):588-590
A fibrous sorbent possessing abundant micropore structure was firstly prepared via post-crosslinking reaction on the PP-ST-DVB original fiber. Its micromorphology and sorptive properties were investigated, and the results demonstrated that the novel fibrous hypererosslinked sorbent has narrow pore-size distribution, small average porous radius (1.90 nm), high specific surface area (362.31 m^2/g), and fine sorptive properties for small organic molecules. 相似文献
8.
A. V. Tvardovskii A. A. Fomkin Yu. I. Tarasevich A. I. Zhukova 《Russian Chemical Bulletin》1995,44(8):1419-1421
The hysteresis of sorptive deformation of sorbents has been studied for the first time. Based on the results obtained, it is assumed that the deformation of sorbents could be the universal reason for the sorptive hysteresis.For Part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1477–1479, August, 1995. 相似文献
9.
Okunev A. G. Sharonov V. E. Gubar" A. V. Danilova I. G. Paukshtis E. A. Moroz E. M. Kriger T. A. Malakhov V. V. Aristov Yu. I. 《Russian Chemical Bulletin》2003,52(2):359-363
Sorption of CO2 in the presence of water vapor by the K2CO3—-Al2O3 composite sorbent was studied by IR spectroscopy in situ, X-ray diffraction analysis, and the differentiating dissolution method and reasons for a decrease in its dynamic capacity are given. The samples containing K2CO3·1.5H2O in pores are characterized by the maximal dynamic capacity. A mechanism for CO2 sorption was proposed, which qualitatively explains the obtained dependence of the capacity on the water content in the composite sorbent. A high dynamic capacity can be maintained by regeneration of the sorbents by water vapor at 170 °N. The capacity of the sorbents decreases during the first 10 sorption—regeneration cycles due to the formation of an inactive phase of potassium aluminum carbonate. 相似文献
10.