• Macromolecular Research
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• v.17 no.9
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• pp.631-637
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• 2009

This study examined the unique self-doping behavior of carboxylated polyaniline (PCA). The self-doped PCA was synthesized using an environmentally benign enzymatic polymerization method with cationic surfactants. XPS showed that HCl-doped PCA contained approximately 34% of protonated amines but self-doped PCA contained 9.6% of the doped form of nitrogen at pH 4. FTIR and elemental analysis showed that although the PCA was doped with the proton of strong acids at low pH via the protonation of amines, the self-doping mechanism of PCA at pH > 4 was mainly due to hydrogen bonding between the carboxylic acid group and amine group.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.817-824
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• 2002

Granular activated carbon(GAC) is highly effective in removing organic compounds which are resistant to biological disintegration in wastewater treatment. However, GAC has reached its full adsorptive capacity, GAC needs to be regenerated before it can be used for a further adsorption cycle. Countercurrent oxidative reaction (COR) technique has been developed and evaluated for the regeneration of spent GAC. Various parameters such as flame temperature, the loss of carbon, destruction and removal efficiency (DRE) of organic compounds, surface area, surface structure, adsorptive capacity, etc. were examined to determine the performance of COR. The results of these tests showed that adosorptive capacity of regenerated GAC was completely recovered, the loss of carbon was controllable, flame temperature was high enough to insure complete destruction and removal $(\geq99.9999%)$ of specific organics of interest, polychlorinated biphenyls (PCBs), that are thermally stable, and on formation of toxic byproducts such as polychlorinated dibenzo-p-dioxins (PCDDs) or polychlorinated dibenzofurans (PCDFs) were detected during the regeneration process. The COR technique is environmentally benign, easy to use and less copital intensive than other available regeneration technologies.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.985-989
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• 2002

For efficient biopulping process, very active and stable lignase is essential. Laccase is one of the best enzyme in terms of environmentally benign processes, since the enzyme uses oxygen as an oxidant to degrade lignin and produces no hamful prod ucts. We could purify a laccase homogeneously from Cerrena unicolor in a very active state. It shows characteristic absorption feature with blue band at λmax = 604 ㎚. Molecular weight of the enzyme is 57,608 which could be accurately determined by MALDI/TOF MS. The enzyme has 2.8 copper ions per enzyme implying apoenzymes might exist together. The enzyme is active in lignin degradation and the activity increases 4 times in the presence of ABTS as a mediator.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1332-1334
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• 2008

Stable crystalline 1-Benzyl-4-aza-1-azonia-bicyclo[2.2.2]octane tribromide (BABOT), can be readily synthesized from the reaction of the corresponding bromide with $HNO_3$ and aqueous KBr. Selective Oxidation of a variety of dialkyl and alkyl Aryl sulfides to the corresponding sulfoxides in high yield was achieved by this reagent in solution ($CH_3CN/H_2O$) and solvent free conditions. The reaction proceeds under neutral and mild conditions and can be carried out easily at room temperature with regeneration of BABOT. In this method purification of products is straightforward and no over oxidation to sulfone was noted.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2968-2972
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• 2013

A highly efficient and environmentally benign protocol has been developed for the first time to produce a wide range of biologically active 5-hydroxyindole derivatives using montmorillonite KSF clay as a reusable solid acid catalyst. The use of recyclable clay makes this procedure quite simple, more convenient and cost-effective.

• Mycobiology
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• v.36 no.1
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• pp.66-69
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• 2008

A simple, efficient and cost effective method is described for the synthesis of Biginelli type heterocyclic compounds of dihydropyrimidinones analogous. They were prepared from a reaction mixture consisting of substituted benzaldehydes, thiourea and ethylacetoacetate using ammonium dihydrogenphosphate as catalyst. The procedure for the preparation of the compounds is environmentally benign and safe which is advantageous in terms of experimentation, catalyst reusability, yields of the products, shorter reaction times and preclusion of toxic solvents. The four new synthesised compounds were tested for their antifungal activity. They have good antifungal activity comparing to the standard (Fluconazole).

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1147-1152
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• 2010

This paper reports a safe and environmentally-benign demilitarization method for the K305 35mm CS gas grenades launcher set(also known as E-8 launcher). The launcher system was disposed by a two-step process; complete recovery of the explosive cords and the gas grenades from the launcher followed by incineration of the recovered items in the APE-1236 Flashing Furnace. All of the 64 grenades within the 16 tubes of the E-8 launcher were safely recovered and incinerated. In this study, 32 sets of the launcher were used to make a standard operating procedure for the safe demilitarization of the launcher system and the 35mm CS cartridges were all safely destroyed in the experimental burning tests meeting the related environmental regulations.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2883-2886
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• 2009

A simple, highly efficient and environmentally benign method for the synthesis of 3-styrylchromones from 3-formylchromones and 4-nitrophenylacetic acid/4-nitrotolune in the presence of catalytic amount of basic ionic liquid 1-butyl-3-methylimidazolium hydroxide [(bmim)OH] carried out under the influence of microwave irradiation. This method gives remarkable advantages such as, short reaction times, simple work-up procedure and moderate to good yields. The ionic liquid was successfully reused for four cycles without significant loss of activity.

• Journal of the Korean Chemical Society
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• v.57 no.2
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• pp.260-263
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• 2013

An efficient and environmentally benign protocol for the pseudo four-component synthesis of benzopyranopyrimidines via condensation of salicylic aldehydes, malononitrile and various amines catalyzed by $ZrOCl_2{\cdot}8H_2O$ as an inexpensive and eco-friendly catalyst with high catalytic activity under solvent-free conditions is reported. This protocol provides a new and improved method for obtaining benzopyranopyrimidines in terms of good yields, simple experimental procedure and short reaction time.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2251-2254
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• 2012

A rapid and practical green route for N-formylation of primary and secondary amines with formic acid at room temperature under the solvent-free conditions using HEU zeolite as a heterogeneous, reusable and highly efficient catalyst is described. The process is remarkably simple and environmentally benign. Excellent chemoselectivity was observed for the conversion of primary amines in the presence of secondary amines.