• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.257-262
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• 2007

Squid viscera oil was investigated by pretreatment method for enhancing the commercial value. Transeterification was performed to reduce rancidity of the oil, off-flavor was removed by using activated carbon adsorption. Analysis using ATD (Automatic Thermal Desorber) and GC/MG shows the efficacy of off-flavor removement. The rates of Transesterification employing inorganic catalyst and biocatalyst were tested, respectively. With stepwise addition of ethanol, the most efficiency of the reaction was achieved by inorganic catalyst. The efficiency of the reaction was estimated by acid value corresponding to rancidity of reaction product.

• Clean Technology
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• v.13 no.3
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• pp.215-221
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• 2007

Biosorption is considered to be a promising alternative to replace the present methods for the treatment of dye-containing wastewater. In this study, sewage sludge was used as a biosorbent which could be one of the cheapest and most abundant biomaterials. The objective of this work is to develop a surface-modified biosorbent with enhanced sorption capacity and binding affinity. The FT-IR and potentiometric titration studies revealed that carboxyl, phosphateand amine groups played a role in binding of dye molecules. The binding sites for reactive dye Reactive Red 4 (RR 4) were identified to be amino groups present in the biomass. In this work, based on the biosorption mechanism, the performance of biosorbentcould be enhanced by the removal of inhibitory carboxyl groups from the biomass for practical application of the biosorbents. As a result, the maximum capacity of biomass was increased up to 130% and 210% of the increment of sorption capacity at pH 2 and 4, respectively. Therefore, chemically modified sewage sludge can be used as an effective and low-cost biosorbent for the removal of dyes from industrial discharges.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.116-116
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• 2011

바이오 가스 플랜트의 혐기소화 공정에서 발생하는 바이오 가스는 중 유해가스인 황하수소($H_2S$)는 부식성 가스로 수천 PPM농도를 함유하여, 발전기나 가스보일러로 이용하는 경우에는 $H_2S$를 제거하는 탈황공정이 반드시 필요하다. 탈황방식에는 산화철 탈황(건식 탈황)과 생물 탈황이 현재 많이 사용되고 있어나 산화철 탈황은 산화철 pellet이 유화철에 변화하면 탈황능력이 저하되어 pellet을 교환해야 하며 많은 비용이 발생한다. 생물 탈황 방식은 유황산화세균의 서식활동조건(온도, 반응시간, 산소량)확보가 반드시 필요하여 높은 운전기술을 필요로 한다. 본 연구에서는 바이오가스 전처리 기술 중 활성탄 또는 약액을 이용한 기존의 탈황정제방식보다 흡착성능이 뛰어난 이온교환섬유를 이용하여, 황화수소($H_2S$)를 95% 이상 제거할 수 있는 고효율 섬유상 이온촉매 악취제거 시스템 개발을 수행하였다. 이온교환섬유는 방사선 조사를 이용하여 부직포에 라디칼을 인위적으로 형성시켜(그라프트 중합) 양이온 또는 양이온을 교환할 수 있도록 제조된 섬유상의 흡착제로, 이온교환 섬유의 화학적 이온교환과 물리적 흡착 및 탈착반응이 동시에 발생되고, 활성탄/실리카켈 보다 흡착능력이 2~4배 높다. 또한 이온섬유의 재생기능을 이용하여 장기적 다양한 악취($H_2S$, $NH_3$, 아민계, 메르갑탄류, 알데히드 등) 및 유해가스(VOCs, NOx, SOx) 등을 95% 이상 제거할 수 있다.

• Korean Chemical Engineering Research
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• v.43 no.4
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• pp.542-547
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• 2005

Biosorption is considered to be a promising alternative to replace or supplement the present methods for the treatment of dye-containing wastewater. In this study, the protonated biomass of Corynebacterium glutamicum was evaluated for its potential to remove two types of reactive dyes (Reactive Red 4, Reactive Blue 4) from aqueous solution. The uptakes of dyes were enhanced with decrease in the solution pH, which was likely because the biomass functional groups increased at acidic pH and the positively charged sites could bind the negatively charged sulfonate group ($dye-SO_3^-$) of dye molecules. An equilibrium state was practically achieved in 10 hr. The Langmuir sorption model was used for the mathematical description of the sorption equilibrium. The maximum sorption capacities of C. glutamicum biomass for Reactive Red 4 and Reactive Blue 4 were estimated to 112.36 mg/g and 263.16 mg/g at pH 1, and 71.94 mg/g and 155.88 mg/g at pH 3.

• Clean Technology
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• v.16 no.2
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• pp.117-123
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• 2010

In this study, we propose two methods able to recover different type of gold from gold-cyanide solutions: biosorption and desorption process for mono-valent gold recovery and biosorption and incineration process for zero-valent gold recovery. The waste bacterial biomass of Corynebacterium glutamicum generated from amino acid fermentation industry was used as a biosorbent. The pH edge experiments indicated that the optimal pH range was pH 2 - 3. From isothermal experiment and its fitting with Langmuir equation, the maximum uptake capacity of Au(I) at pH 2.5 were determined to be 35.15 mg/g. Kinetic tests evidenced that the process is very fast so that biosorption equilibrium was completed within the 60 min. To recover Au(I), the gold ions were able to be successfully eluted from the Au-loaded biosorbent by changing the pH to pH 7 and the desorption efficiency was 91%. This indicates that the combined process of biosorption and desorption would be effective for the recovery of Au(I). In order to recover zero-valent gold, the Au-loaded biosorbents were incinerated. The content of zero-valent gold in the incineration ash was as high as 85%. Therefore, we claim on the basis of the results that two suggested combined processes could be useful to recover gold from cyanide solutions and chosen according to the type of gold to be recovered.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.449-456
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• 2020

When you move to a new home, or when you change the wallpaper or flooring of your home, office, etc., you can enjoy the joy of opening your new home with the sick house syndrome, such as the stinging smell and stinging eyes that may appear after the interior work. It is only a moment. Volatile organic compounds from building materials, adhesives, wallpaper, and paints used in new buildings or new furniture cause residents' health and discomfort in indoor life. These volatile organic compounds include benzene, toluene, acetone, and styrene, as well as the representative formaldehyde, and these substances are slowly released over a long period of time, causing acute or chronic diseases to residents. As a method for removing organic volatile substances, physical methods using adsorption, chemical methods for converting volatile substances to other substances, or a mixture of the two are mainly used. In this paper, a sustained release chlorine dioxide gel pack obtained by a method for controlling the reaction rate of a reactant and the release of a product is mixed with a zeolite adsorbent having an optimized hole diameter to adsorb and decompose and remove formaldehyde suspended in the air. I would suggest an effective method.

• Analytical Science and Technology
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• v.28 no.1
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• pp.40-46
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• 2015

Hydrochar has been generated from food waste via hydrothermal carbonization (HTC) reaction. As a solid product of HTC reaction, hydrochar has a great potential as an adsorbent of pollutants from the various media. The surface area and pore volumes are very important parameters to be served as an adsorbent. It requires an expensive equipment and consumes time to measure those parameter. Therefore, titration methods including iodine and methylene blue adsorption were evaluated to be correlated with that of BET analysis. Even though the absolute values of the computed surface area and pore volumes were not able to be matched directly, the patterns of change were successfully correlated. Among the reaction conditions, the reaction time and temperature at $230^{\circ}C$ for 4 h was determined as an optimization condition, which confirmed by titration method and BET analysis. Titration method for surface area and pore volumes computed by combination of iodine and methylene blue adsorbing values would be a simple and fast way of determining the optimization condition for hydrochar as an adsorbent produced by HTC reaction.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.25-31
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• 2021

In this research, in order to effectively utilize the petroleum residue pitch, it was used as an adsorbent for removal of cesium ion. In this experiment, acid modification (hydrochloric acid, sulfuric acid) treatment was performed on the adsorbent to improve the ability to remove low-concentration cesium ions dissolved in water. As a result, when the reaction was performed with 9 M sulfuric acid at 25 ℃ and for 240 min, the removal efficiencies of 1.0 and 2.5 mg/L cesium ions were 66 and 51%, respectively. In addition, as the adsorption time increased in the batch experiment, the removal capacity of 1.0 and 2.5 mg/L cesium ions was improved, and when the adsorption reached for 32 hr, the removal efficiencies were 72 and 68%, respectively. Also, in order to increase the ability to remove the remaining cesium ions, an experiment was performed by temperature change (25, 37, 49 ℃), and 1.0 and 2.5 mg/L cesium ions contained in water under the operating conditions of 49 ℃ and 32 hr showed removal efficiencies of 90 and 81%, respectively. Consequently, these experimental results were intended to be used as an adsorption technology that can economically treat low-concentration cesium ions contained in water.

• Membrane Journal
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• v.28 no.2
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• pp.136-141
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• 2018

Carbon dioxide ($CO_2$) exists not only as a component of natural gas, biogas, and landfill gas, but also as a major combustion product of fossil fuels which leads to a major contributor to greenhouse gases. Hence it is essential to reduce or eliminate carbon dioxide ($CO_2$) in order to obtain high fuel efficiency of internal combustion engine, to prevent corrosion of gas transportation system, and to cope with climate change preemptively. In recent years, there has been a growing interest in not only conventional membrane-based separation but also new adsorbent-based separation technology. Particularly, in the case of metal-organic frameworks (MOFs), it has been received tremendous attentions due to its unique properties (eg : flexibility, gate effect or strong binding site such as open metal sites) which are different from those of typical porous adsorbents. Therefore, in this study, stereotype of two MOFs have been selected as its flexible MOFs (MIL-53) representative and numerous open metal sites MOFs (MOF-74) representative, and compared each other for $CO_2/CH_4$ separation performance. Furthermore, varying and changeable separation performance conditions depending on the temperature, pressure or samples' unique properties are discussed.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.367-375
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• 2006

Sequencing Batch Reactor (SBR) is well adopted for community wastewater treatment for its simplicity, performance and various advantageous treatment options. SBR is now drawing attention for its process modification such as coupled with membrane bioreactor, reverse osmosis or applying different media to achieve high removal efficiency. This study focused on the improved efficiency of carbon, nitrogen and phosphorous removal by applying zeolite materials called bioceramics to the SBR. Two laboratory-scale SBR units were operated in the same operating conditions - one with bioceramics called Bioceramic SBR (BCSBR) and the other without bioceramics used as control. Routine monitoring of COD, TP, $NH_3-N$, $NO_3-N$ was performed throughout this study. COD removal was about 80% to 100% and phosphorous removal was about 60% in the process whereas $NH_3-N$ removal efficiency was found to be 99.9% in the BCSBR unit. Addition of bioceramics also improved sludge characteristics such as sludge dewaterability, specific gravity and particle size. BCSBR can withstand high ammonia shock loading leading to the better treatment capacity of high ammonia containing wastewater. The cause of improved removal efficiencies within the biological reactor could be attributed to the biochemosorption mechanisms of bioceramics. Absorption/adsorption or desorption capacity of bioceramics was tested through laboratory experiments.