• 환경영향평가
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• 제29권3호
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• pp.198-209
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• 2020

본 연구는 실내공기질의 평가지표인 이산화탄소를 효과적으로 제어하기 위해, 활성탄소 나노섬유를 이용한 흡착·제어기술을 연구하고자 하였다. 연구는 PAN(Polyacrylonitrile) 전구체 용액을 사용한 전기방사(electrospinning) 방법으로 제조된 나노섬유를 고온에서 활성화하여 비표면적과 미세공 부피를 증가시켰다. 다음 단계로, 제조된 활성탄소 나노섬유 표면을 70% HNO₃로 산화처리한 후, TEPA(tetraethylenepentamine)용액으로 함침시킴으로 섬유표면의 알칼리성을 증진시켰다. 일련의 조건으로 제조된 활성탄소 섬유들에 대한 이산화탄소(3000 ppm)의 흡착능을 평가하는 실험을 진행하였다. 활성화 시간（30분, 60분, 90분)이 길어질수록 섬유 표면의 비표면적과 총 세공부피가 증가하였는데, 섬유표면의 비표면적은 308.4 ㎡/g에서 839.4 ㎡/g으로 증가하였고, 총 세공부피는 7.882 ㎤/g에서 27.50 ㎤/g으로 증가하였다. TEPA 함침 할 경우, 미세공의 막힘으로 인해 활성탄소섬유의 비표면적과 세공부피가 크게 감소하였지만, HNO₃ 산화처리에 의해 아민량이 6.42%에서 17.19%로 증가한 결과, 이산화탄소 흡착능을 향상시킬 수 있는 것으로 분석되었다. 결론적으로, 활성탄소 섬유에 대한 60분간 활성화 과정과 HNO₃와 TEPA 함침 처리 등의 일련의 과정을 거친 흡착제(60-ANF-HNO₃-TEPA)의 저농도(0.3%) 이산화탄소(N₂ 가스와 혼합)의 흡착능이 가장 우수한 것으로 확인되었다. 이러한 결과는 실내공기 중 저농도 이산화탄소도 효율적으로 흡착·제어할 수 있는 기술로 활용될 수 있으리라 사료된다.

• Korean Chemical Engineering Research
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• 제53권3호
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• pp.382-390
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• 2015

Poly(methyl methacrylate) (PMMA) supports and amine additives were investigated to adsorb $CO_2$. PMMA supports were fabricated by using different ratio of pore forming agents (porogen) to control the BET specific surface area, pore volume and distribution. Toluene and xylene are used for porogens. Supported amine sorbents were prepared by wet impregnation of tetraethylenepentamine (TEPA) on PMMA supports. So we could identify the effect of the pore structure of supports and the quantity of impregnated TEPA on the adsorption capacity. The increased amount of toluene as pore foaming agent resulted in the decreased average pore diameter and the increased BET surface area. Polymer supports with huge different pore distribution could be fabricated by controlling the ratio of porogen. After impregnation, the support with micropore structure is supposed the pore blocking and filling effect so that it has low $CO_2$ capacity and kinetics due to the difficulty of diffusing. Macropore structure indicates fast adsorption capacity and low influence of amine loading. In case of support with mesopore, it has high performance of adsorption capacity and kinetics. So high surface area and meso-/macro- pore structure is suitable for $CO_2$ capture.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3668-3674
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• 2010

Mesoporous SBA-15 was synthesized using tetraethylorthosilicate (TEOS) as the silica source and Pluronic (P123) as the structure-directing agent. The defective Si-OH groups present in SBA-15 were successively grafted with 3-chloropropyltrimethoxysilane (CPTMS) followed by tris-(2-aminoethyl) amine (TAEA) and/or tetraethylenepentamine (TEPA) for effective immobilization of silver nanoparticles. Grafting of TAEA and/or TEPA amine and immobilization of silver nanoparticles inside the channels of SBA-15 was verified by XRD, TEM, IR and BET techniques. The silver nanoparticles immobilized on TAEA and /or TEPA grafted SBA-15 was subjected for electrocatalytic reduction of hydrogen peroxide ($H_2O_2$). The TEPA stabilized silver nanoparticles show higher efficiency for reduction of $H_2O_2$ than that of TAEA, due to higher number of secondary amine groups present in TEPA. The amperometric analysis indicated that both the Ag/SBA-15/TAEA and Ag/SBA-15/TEPA modified electrodes required lower over-potential and hence possess high sensitivity towards the detection of $H_2O_2$. The reduction peak currents were linearly related to hydrogen peroxide concentration in the range between $3{\times}10^{-4}\;M$ and $2.5{\times}10^{-3}\;M$ with correlation coefficient of 0.997 and detection limit was $3{\times}10^{-4}\;M$.