• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.239-247
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• 2016

This study aims to examine absorption characteristics of toluene, isopropyl alcohol (IPA), ethyl acetate (EA), and ternary-compounds, all of which are widely used in industrial processes, by means of four types of commercial activated carbon substances. It turned out that among the three types of volatile organic compounds, the breakthrough point of activated carbon and that of IPA, whose affinity was the lowest, were the lowest, and then that of EA and that of toluene in the order. With the breakthrough point of IPA, which was the shortest, as the standard, changes in the breakthrough points of unary-compounds, binary-compounds, and ternary-compounds were examined. As a result, it turned out that the larger the number of elements, the lower the breakthrough point. This resulted from competitive adsorption, that is, substitution of substances with a low level of affinity with those with a high level of affinity. Hence, the adsorption of toluene-IPA-EA and ternary-compounds require a design of the activated carbon bed based on the breakthrough of IPA, and in the design of activated carbon beds in actual industries as well, a substance whose level of affinity is the lowest needs to be the standard.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.515-517
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• 2007

• Journal of Korea Soil Environment Society
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• v.5 no.3
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• pp.17-23
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• 2001

The adsorption and movement characteristics of herbicide pendimethalin was studied in three kinds of soil, sandy loam, silty clay and loam. The results of the batch test and columnexperimentweresummarizedasfollows. The shaking time reached to the adsorption equilibrium of pendimethalin in soils was 6 hours. The adsorption rates of pendimethalin for sandy loam, silty clay and loam were 59.6%, 77.3% and 64.0%, respectively. The adsorption isotherms with the Freundlich equation showed better consistency than that with the Langmuir one. The adsorption coefficients of pendimethalin for soils were 8.0. 16.1 and 9.5. respectively. When breakthrough point was 0.05Co, the breakthrough times reached for soils were 256 minutes, 810 minutes and 420 minutes. respectively.

• Resources Recycling
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• v.9 no.6
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• pp.9-14
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• 2000

Comparing the adsorption characteristics of coconut shell activated carbon (CSAC) and waste paint activated carbon (WPAC), Freundlich adsorption isotherms of alkylbenzene sulfonate (ABS) obtained from the secondary treatment water of H company and effluent of D company were estimated q=23.12 $C^{0.42}$ , q=18.32 $C^{0.38}$ with WPAC and $q=36.76C^{1.37}$ /, q=26.67 $C^{0.42}$ with CSAC respectively. In the case of H company, breakthrough time of the ABS using CSAC by continuous experiment was estimated 680 minute md that of WPAC was 610 minute. In the case of D company effluent, CSAC was estimated 720 minute, and that of WPAC was estimated 640 minute to reach the breakthrough. From the above results, it is possible to replace the coco-nut shell activated carbon with wasted paint activated carbon.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.203-206
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• 2004

활성탄 흡착을 통한 도장공정의 건조작업시 발생하는 VOCs 가스중에서 많은 양을 차지하는 톨루엔의 흡착실험의 결과는 아래와 같다. 활성탄을 충전한 고정흡착탑에서 톨루엔의 흡착에 있어서 파과곡선의 파과점은 흡착제의 포화특성에 좌우되며, toluene 가스의 농도, 유량이 증가할수록 감소하였다. 활성탄의 동일한 충전층에 대해 toluene 가스의 유량, 농도가 증가할수록 MTZ와 LUB도 증가함으로 흡착층의 효율이 감소하는 것으로 나타났다.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.83-91
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• 1997

Phenolic acids are regarded as harmful materials in food and environment science. But recently, regarded as useful materials by their characteristics which bind metal ions and have pharmaceutical effect. It was necessary to remove or recover phenolic acids from solutIon containing phenolic acids. Continuous fixed-bed adsorption was adapted in order to separate phenolic acids from diluted solution and the breakthrough curve was predicted by nonlinear curve fitting method. The larger bed length showed the longer breakpoint time and the slow mass transfer coefficient. Ferulic acid among the phenolic acids was passed through the breakpoint first and the second and. third were p-coumaric acid and gallic acid. These orders were caused by not only ionic strength between adsrobent and adsorbate but also molecular weights.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1132-1138
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• 2008

The study was carried out to investigate adsorption characteristic on hydrogen sulfide (H$_2$S) and methylmercaptan (CH$_3$SH) odor gas using the char made by a thermal decomposition of sewage sludge. The fixed bed adsorption experiments of the optimum L/D ratio could be 1.0, and adsorption capacity and break point increased with the increase of temperature. A simultaneous adsorption characteristic of H$_2$S and CH$_3$SH increased in breakthrough time and adsorption capacity more than single adsorption experiment, and CH$_3$SH had higher effective diffusivities than H$_2$S in same condition. The adsorption capacity of CH$_3$SH increased with fast velocity. When it was compared the produced absorbent with commercial activated carbon, As to adsorbent amount, it was H$_2$S 77% and CH$_3$SH 80% of commercial activated carbon.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.281-288
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• 2002

Crab shell 충진 칼럼을 이용한 수중 중금속의 연속적 제거에 있어서 다른 흡착제 (CER, GAC, Zeolite)와 비교 실험을 통하여 crab shell의 중금속 제거능을 알아보았다. 수중 $Pb^2+/{2+}$ 의 column을 이용한 연속적제거에 있어서 미세침전부분이 외부로 배출됨으로 칼럼 외부에 여과시스템의 도입함으로써 중금속 제거능을 높일 수 있을 것으로 판단된다. 중금속의 연속적 제거에 있어서 CER의 1,000 BVs까지의 전체 제거량은 0.35mmol/g, GAC는 0.17mmo1/g, zeolite는 0.16 mmol/g으로 나타났고 crab shell에 의한 중금속 제거량은 0.61 mmol/g으로 다른 흡착제보다 높은 제거효율을 보였다. 수중 중금속의 연속적 제거에 있어서 여러 흡착제의 제거 순서는 crab shell > CER > GAC > zeolite 로 나타났다. Crab shell의 경우는 파과점이 2,000 BVs에서 나타나므로 일반적인 폐수처리의 화학적 처리 후 잔존하는 저농도의 중금속을 제거를 위해 crab shell 충진 칼럼이 유용 할 것으로 판단된다. Crab shell의 재사용 가능성을 알아보기 위하여 crab shell을 이용한 중금속 제거공정에서 연속적인 중금속제거와 탈착과정을 통하여 보았을 때 1회에서 $Pb^2+/{2+}$제거된 량은 0.71 mmol/g 제거되었고 2회에서는 0.27 mmol/g, 3회에서는 0.02 mmol/g으로 급격하게 crab shell의 제거능이 떨어지는 것을 관찰 할 수 있다. 이는 crab shell이 재사용이 불가능 할 것으로 판단되나 다른 흡착제보다 월등한 제거효율을 보이므로 수중 중금속의 연속적 제거 흡착제 적합할 것으로 판단된다.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.366-369
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• 2008

To evaluate the performance of a bipolar packed bed cell (BPBC) filled with granular aluminium, the experiments were carried out in two groups as batch and continuous processes. In a batch process, removal efficiency of total phosphate (T-P) was 88% in case of electrolytic treatment of phosphate solution, T-P 10 mg/L at 6 V during 3 h by BPBC filled with granular aluminium. In a continuous process, residual T-P concentration was about 2 mg/L in case of electrolytic treatment of phosphate solution, 10 mg/L at 6 V, HRT 3 h by BPBC filled with granular aluminium. Break-through point was observed after running for 120 h at hydraulic retention time (HRT) of 3 h.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.377-380
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• 2015

In this paper, we have investigated the optimization of $I_2$ recovery process from $NH_4I$ solution, which is generated as by-product during the amination reaction of p-diiodobenzene (PDIB) for p-phenylenediamine (PPD) synthesis. The recovered $I_2$ is then recycled as a raw material for PDIB synthesis. We have employed a cation exchange resin to recover $I_2$ from $NH_4I$ sample solution, and determined the breakthrough point and exchange capacity from the breakthrough curve. Furthermore, we have suggested optimum conditions of our $I_2$ recovery process by measuring the purity and yield of recovered $I_2$ with respect to the concentrations of $NH_4I$ and oxidant ($H_2O_2$) solutions, the oxidation time, and the temperature of drying process. Finally, the yield and purity as high as 94.96% and 96.65%, respectively were obtained by reusing the residual solution still containing unrecovered iodide ions.