• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1303-1305
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• 1998

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.357.2-359
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• 1992

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.238-245
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• 1991

Chlorination of methane was carried out over the Pt/NaY zeolite catalysts having different dispersion and location. On the finely dispersed platinum particles inside the zeolite methylchloride was the sole product, while on the large platinum ones outside surface of the zeolite all four chloromethanes were produced. Besides the role of highly dispersed platinum particles, the confined volume of the supercages in the support seems to have played another role on the exclusive production of methylchloride by restricting the further chlorination.

• Environmental Engineering Research
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• v.22 no.1
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• pp.108-115
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• 2017

Chlorination has been the most common antifouling method, but alternatives are under searching. In this article, we report how the hydrogen peroxide could enhance the effect of chlorination to prevent fouling by inhibiting larvae settlement and abatement of mussel colonization or by extinct of them; through marine mussel Mytilus edulis. The addition of hydrogen peroxide shows synergic effect on the veliger larvae (up to 19 folds) and effectively reduces required time of mussel mortality by 8-22%. For resolution of micro- and macro-fouling caused by the marine mussel, as well as diminishing of time and conventional chlorine dose could be important factor in favour of environment and economics.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.266-270
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• 2005

본 연구는 Ta, Nb, Zr, 및 희토류 등을 복합적으로 함유한 복합광을 대상으로 사염화탄소에 의한 염화반응을 알아보기 위한 기초연구로서 각 산화물의 염화반응 특성을 알아보고 이를 토대로 복합광의 염화반응을 비교하여 보았다. 실험결과 산화물 상태의 Nb, Ta 및 Zr은 비교적 낮은 온도에서 염화반응이 일어나고 염화물이 휘발됨을 알 수 있었다. 복합광을 반응 온도 $400^{\circ}C,\;CCl_4$ 분압 0.28 일때 반응시간이 10분에서 60분으로 변함에 따라 니오븀 및 탄탈륨은 $91%{\sim}99%$의 높은 회수율을 나타내었으나 지르코늄은 각각 16.5%에서 27.5%로 약간 증가하는 경향을 나타내었다. 희토류의 경우 세륨은 반응율이 71.7에서 73% 정도였고 란타늄은 51%에서 54% 정도의 반응율을 나타내었다.

• Membrane and Water Treatment
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• v.4 no.1
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• pp.69-81
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• 2013

The pH-dependent inter-conversion of the three free chlorine species ($Cl_2$, HOCl, OCl-) present in the aqueous hypochlorite solution was theoretically investigated. Each species was found overwhelmingly present in a characteristic pH range. Hypochlorite treatment of the polyamide membrane was carried out over these pH ranges and various membrane responses were observed. As pH is less than 8, membrane tends to be N-chlorinated by $Cl_2$ and HOCl, and N-chlorinated membrane showed reduced water permeance and salt rejection. As pH rises to 10-12, $OCl^-$ appears to be the dominating chlorine species. Membrane hydrolysis was found to well interpret the improved water permeance and salt rejection. When the pH is between 8-10, both N-chlorination and hydrolysis contribute to the response of the membrane, and the treated membrane showed improved salt rejection but reduced water permeation. Excessive hydrolysis occurred while the membrane was treated at pH 13 for the much stronger alkalinity.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3434-3436
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• 2010

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3692-3695
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• 2011

Poly(N,N'-Dichloro-N-ethyl-benzene-1,3-disulfonamide) (PCBS) and N,N,N',N'-Tetrachlorobenzene-1,3-disulfonamide (TCBDA) were found to be a mild and efficient reagent for the direct oxidative conversion of sulfur compounds to the corresponding arenesulfonyl chlorides in good to excellent yields through the oxidative chlorination. The overall process is simple, practical, and it provides convenient access to a variety of aryl or heteroarylsulfonyl chlorides. The mild reaction conditions and the broad substrate scope render this method attractive, and complementary to existing syntheses of aryl or heteroarylsulfonyl chlorides.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.535-540
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• 1997

Potassium carbonate reacts with silicon tetrachloride to form trichlorosilyloxy carbonylchloride which reacts subsequently with another molecule of silicon tetrachloride leading to phosgene eventually in chlorinated solvents. This in situ generated trichlorosilyloxy carbonylchloride or phosgene were found to be very effective for the chlorination of a wide variety of alcohols to the corresponding chlorides. Primary, secondary and benzylic alcohols were converted into corresponding chlorides when treated with silicon tetrachloride in the presence of potassium carbonate at room temperature.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.276-283
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• 2018

For the first time, polyvinyl chloride (PVC) was used as an easily-handled chlorine source for preparation of isotropic pitch-based carbon fiber (IPCF) incorporating ethylene bottom oil (EO) as a raw material. Pitch precursors were prepared by the chlorination-dehydrochlorination triggered by chlorine radicals originated from PVC; aromatization and poly-condensation reactions occurred by polyene-type radicals from PVC. Radical production and co-carbonization were facilitated by pretreatments of EO through vacuum distillation, bromination, and additional heat treatment. Pitches were prepared by the co-carbonization of pretreated EO and EO containing 20 wt% PVC, and had higher yields and better spinnability than those by simple distillation.