• Applied Chemistry for Engineering
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• v.31 no.5
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• pp.575-580
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• 2020

In this study, we simulated an amine regeneration process with heat-stable salts removal unit. We derived the optimal operating conditions considering the flow rate of waste, the removal rate of heat-stable salts, and the loss rate of MDEA (methyl diethanolamine). In the amine regeneration process that absorbs and removes acid gas, heat-stable salt impairs the absorption efficiency of process equipment and amine solution. An ion exchange resin method is to remove heat-stable salts through neutralization by using a strong base solution such as NaOH. The acid gas removal process was established using the Radfrac model, and the equilibrium constant of the reaction was calculated using Gibbs free energy. The removed amine solution is separated and flows to the heat-stable salts remover which is modeled by using the Rstoic model with neutralization reaction. Actual operation data and simulation results were compared and verified, and also a case study was conducted by adjusting the inflow mass of removal unit followed by suggesting optimal conditions.

• Journal of the Korean Electrochemical Society
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• v.13 no.1
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• pp.50-56
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• 2010

The multi-wall carbon nano-tube composite mixed with carbon paste electrode presented more sensitive and selective amperometric signals in the oxidation of glucose than general screen-printed carbon electrodes(SPCEs). Redox mediators to transport electrodes from enzyme to electrodes are very important part in the biosensor. A novel osmium redox complex was synthesized by the coordinating pyridine group containing primary amines which were electrochemically immobilized onto the MWCNT-SPCEs surface. Electrochemical studies of osmium complexes were investigated by cyclic voltammetry, chronoamperometry. The surface coverage of osmium complexes on the modified carbon nano-tube electrodes were significantly increased at 100 time (${\tau}_0=2.0\;{\times}\;10^{-9}\;mole/cm^2$) compared to that of the unmodified carbon electrodes. It's practical application of the glucose biosensor demonstrated that it shows good linear response to the glucose concentration in the range of 0-10 mM.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.471-481
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• 1992

This study is related to the reactivity of dioxygen bridged palladium complexes having amine ligands. New dloxygen bridged palladium complexes were prepared using superoxide ion(${O_2}^-$) as an oxygen source. The reactions of dioxygen palladium complexes prepared in the study were examined in order to clarify the nature of the coordinated dioxygen. Treatments of a solution of the dioxygen bridged palladium complexes in benzene by water, methanol, acetic acid gave hydrogen peroxide($H_2O_2$) and hydroxy, methoxy, acetoxy-bridged palladium complexes, respectively. The dioxygen bridged palladium complexes reacted with substitution phenols of salicylaldehyde, 8-hydroxyquinoline and active mothylenes of acetylacetone, dimethyl malonate to afford mononuclear complexes of palladium and hydrogen peroxide. Furthermore, she dioxygen bridged palladium complexes changed to acetonyl bridged palladium complex and hydrogen peroxide reacting with acetone. The results suggest that dioxygen is coordinated as peroxo (${O_2}^{2-}$) in the complexes and behaves as a strong base.

• KSBB Journal
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• v.19 no.4
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• pp.274-283
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• 2004

Six lumbrokinase (LK) fractions from Lumbricus rubellus lysates were purified by a series of column chromatographies. The molecular weights of the six LK fractions appeared to range from 24.6 to 33.1 kDa. In the experimental model of rat venous thrombosis, the thrombus weight and PAI activity decreased significantly when the LK was administered orally. However, the activities of APTT, PT and plasmin showed a significant increase. The aggregation of rat platelets pretreated with various LK doses was inhibited by thrombin, and the MDA generation decreased. The rat thoracic aorta and mesentric arteries contracted with phenylephrine relaxed due to the treatment of the LK fractions. These results suggest that the fibrinolytic effects of LK were mediated not only by proteolytic activity, but also by the inhibition of platelet agregation and the relaxation of blood vessels. It is concluded that the LK may be useful as a hemolytic agent for treatment of fibrin clot.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.229-237
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• 1991

Vinylester was syntheszed in the presence of amine and metal catalysts, such as triethylamine(TEA), triethylbenzyl ammonium chloride (TEBAC), cetyltrimethyl ammonium bromide (CTMAB), chromium acety] acetate (CAA), and triphenylantimony (TPA). Apropriate use of amine and organometal catalysts were 1.7~2.2 % (Wt. %), 2.5~3.1 % (Wt %) of charged methacrylic acid (MAA) in respect of reactivity, gel-time, and storage stability. The Order of reactivity was TEA>TEBAC>CTMAB>CAA>TPA. Temperature independence of catalyst showed more large deviation above $110^{\circ}C$. Storage stability could be improved without delay of gel-time by adding TPA in 2.0 % (Wt %) of charged MAA after synthesis.

• Analytical Science and Technology
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• v.6 no.5
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• pp.435-442
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• 1993

Carboxymethylated polyamine-polyurea resin loaded with rubeanic acid (RCCPPI resin) was obtained by 1 step chemical reaction between chlorocarboxymethylated polyamine-polyurea(CCPPI) resin as matrix polymer and rebeanic acid. This resin was confirmed with infrared spectrometry, elemental analysis, and thermal analysis(DSC). The adsorption characteristics of the heavy metal's on the resin were studied by measuring distribution coefficient($K_d$) with changing pH of the solutions and frontal chromatography. The enrichment, recovery, and analysis of trace heavy metals, such as cadmium, cerium, copper, nikel, lead, and zinc, in the presence of high concentrations of sodium, calcium, and acetate salts was possible quantitatively by a column packed with the resin at each optimum pH. Preconcentration factors were more than 25. To elute the adsorbed heavy metals on the resin, 0.025M EDTA solution(pH 9.0) was used.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.775-782
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• 2009

PP-g-AA-Am nonwoven fabric, which possess anionic exchangeable function, was prepared by chemical modification of carboxyl (-COOH) group of PP-g-AA nonwoven fabric to amine ($-NH_2$) group using diethylene triamine (DETA). Its adsorption characteristics for anionic nutrients including isotherm, kinetics and co-anions were studied by batch adsorption experiments. Adsorption equilibriums of $PO_4$-P on PP-g-AA-Am fabric were well described by the Langmuir isotherm model, and their adsorption energies were ranged 10.3 kJ/mol indicating an ion-exchange process as primary adsorption mechanism. The adsorption selectivity of PP-g-AA-Am nonwoven fabric for anions under competition with each other was in following order: $SO_4\;^{2-}$>$PO_4\;^{3-}$>$NO_3\;^-$>$NO_2\;^-$. Also, all results obtained from this study indicate that the $PO_4$-P removal capacity of PP-g-AA-Am nonwoven fabric was extremely superior to that of PA308 anion-exchange resin.

• Analytical Science and Technology
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• v.7 no.2
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• pp.205-211
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• 1994

Acetic acid and succinic acid bonded polyamine-polyurea(CPPI and SAPPI) resins were synthesized from the reaction of polyethylenimine-polymethylenepolyphenylene isocyanate(PPI) resin as matrix polymer and chloroacetic acid and chlorosuccinic acid respectively. These resins were confirmed with infrared spectrometry and elemental analysis. The adsorption characteristics of the chromium(III) and dichromate(or chromate) ions on the resins were studied by measuring distribution coefficients($K_d$) with changing pH of the solution. It was thought that these ions were adsorbed by ion exchange mechanism. Chromium(III) and dichromate ion could be separated with stepwise elution method by changing pH of the eluent using SAPPI resin packed column($0.6cm(i.\;d.){\times}10cm(L.)$). Also, dichromate ion could be preconecntrated with CPPI resin column by a concentration factor of 50.

• Polymer(Korea)
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• v.36 no.4
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• pp.470-477
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• 2012

A tyrosinase-immobilized biosensor was developed based on various amine-modified multi-walled carbon nanotube (MWNT) supports for the detection of phenolic compounds. MWNTs with various amine groups were prepared by radiation-induced graft polymerization of glycidyl methacrylate (GMA) onto MWNT supports and the subsequent amination of poly(GMA) graft chains. The physical and chemical properties of the poly(GMA)-grafted MWNT supports and the aminated MWNT supports were investigated by SEM, XPS, and TGA. Furthermore, the electrochemical properties of the prepared tyrosinase-modified biosensor based on MWNT supports with amine groups were also investigated. The response of the enzymatic biosensor was in the range of 0.1-0.9 mM for the concentration of phenol in a phosphate buffer solution. Various parameters influencing biosensor performance have been optimized: binder effects, pH, temperature, and the response to various phenolic compounds. The biosensor was tested on phenolic compounds contained in two different commercial red wines.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.142-143
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• 2000

클로로메틸화된 스티렌-디비닐벤젠 담체에 입체적으로 bulky한 3차 아민을 반응시켜 $NEt_3$과 $N(CH_2$$CH_2$$OH)_3$를 관능기로 가지는 이온교환수지를 합성하였으며, 실험을 통해 $SO_{4}^{2}$보다는 $NO_3$를 우선적으로 제거할 수 있음을 확인하였다.