• 대한화학회지
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• 제20권3호
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• pp.206-211
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• 1976

비수용액 에틸렌디아민 중에서 산-알칼리의 전위차 중화 적정 이론을 고찰하여 실험한 결과 이론과 잘 일치하였다.

• 대한화학회지
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• 제48권2호
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• pp.189-194
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• 2004

이 연구에서는 산-염기 중화반응의 실험 방법에 관련된 과학 교과서 내용을 분석하고, 문제점을 개선하는데 목적이 있다. NaOH-HCl 수용액의 중화반응실험에서 1) 페놀프탈레인의 decoloration, 2) 염 생성 확인을 위해 적정된 용액의 농축을 위한 가열 과정에서의 색 변화, 3) 염 결정 확인의 어려움이 문제점으로 지적되었다. 이러한 문제점들은 페놀프탈레인의 구조변화에 근거하여 설명하였고, 개선된 실험방법을 제시하였다.

• 청정기술
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• 제3권2호
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• pp.74-86
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• 1997

최근 청정기술의 필요성이 증가하면서 막분리 공정에 의한 산업폐수 처리기술에 대한 관심이 높아가고 있다. 이 연구는 중화법과 water-splitting electrodialysis (WSED)를 이용하여 금속을 포함하고 있는 폐수에서 유용한 물질을 회수하고 무방류계를 실현하기 위한 것이다. 본 연구에서는 산폐수와 혼합폐수 처리의 공정 설계를 위한 공정의 흐름를 확립하였고, 이 공정에 따른 물질수지를 계산하였다. 또한 주요 단위공정인 침전조와 산회수공정의 운전인자에 대한 실험을 수행하였다. 침전공정에서는 KOH와 NaOH를 중화제로 이용하여 pH에 따른 침전효율과 슬러지양을 비교하였으며 산회수 공정에서는 KCl과 NaCl을 합성원료로 이용하여 WSED의 막구조에 따른 회수효율을 조사하였다.

• 자원환경지질
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• 제41권1호
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• pp.33-45
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• 2008

폐광산으로부터 유출되는 산성광산배수 중화처리를 위해 2가지 방법으로 반응조를 설계하여 실험을 실시하였다. 중화제로 사용한 물질은 방해석이 주 구성광물이여 소량의 돌로마이트를 포함한 석회암이다. 중화 효과는 중화제의 반응 위치와 양에 따라 다르게 나타난다. 반응조 상부에서 산성광산배수와 중화제를 반응 시킬 때 반응 효과가 더 좋으며 중화제의 양이 많을수록 중화되는 속도가 빠르다. 상부에서 중화제와 반응시킬 경우 산성광산배수로부터 침전되는 침전물의 영향을 거의 받지 않아 중화제가 전부 소모될 때까지 반응을 지속시킬 수 있다.

• 한국토양비료학회지
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• 제50권6호
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• pp.606-614
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• 2017

Amount of food waste has been increased annually in Korea and re-use of food waste as a fertilizer or soil amendment in agricultural field has been studied. Therefore, main purpose of this research was to determine optimum condition of hydrolysis for food waste management. Three different solvents, HCl, $H_2SO_4$, and KOH, were used and varied concentration at the range of 10~30% and hydrolysis time at the range of 1~3 hours were evaluated. In general, reduction rate of food waste was increased when concentration of solvent and hydrolysis time was increased except when KOH was used. Among different solvents, concentration, and hydrolysis time, the highest reduction rate (97.79%) was observed when 30% of HCl was used with temperature of $140^{\circ}C$ at 2 hours of hydrolysis time. In addition, neutralization effect of alkalic materials, shell waste (SW) and egg shell (ES) was evaluated. Both SW and ES increased pH of finished acid hydrolysis solution up to 7.61 indicating that neutralization effect of SW and ES was sufficient for finished acid hydrolysis solution. Contents of organic matter was also at the range of 10.7~13.04% and 5.53~8.04% respectively when HCl and $H_2SO_4$ were used as solvent. Overall, hydrolysis technique can be used to manage food waste with selected optimum condition in this study and characteristics of finished hydrolysis solution after neutralization might be suitable for soil amendments.

• 신재생에너지
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• 제19권4호
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• pp.2-10
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• 2023

The current mandatory domestic biodiesel blending ratio is 3.5%, which is planned to be gradually increased to achieve carbon neutrality by 2050. The aim of this study was to improve domestic self-sufficiency in biodiesel raw oil by conducting a technical review on the possibility of utilizing waste oils, such as soup oil, chicken oil, and leather oil, as biodiesel feedstocks. These waste oils have an acid value that is too high to be converted directly into biodiesel. Therefore, a pretreatment to reduce the acid value is necessary. The neutralization process was examined as a potential technology for reducing the acid value. The oil recovery rate of the soup oil after neutralization was significantly low at 37.6 wt%. The oil recovery rates of leather oil and chicken oil were 66.49 wt% and 79.08 wt%, respectively. Based on biodiesel conversion experiment using waste oil with a reduced acid value, the conversions were analyzed as 89 wt%, 91.1 wt%, and 90.5 wt% for soup oil, leather oil, and chicken oil, respectively. Thus, it is technically possible to use soup oil, leather oil, and chicken oil as raw materials for producing biodiesel.

• 대한지하수환경학회지
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• 제2권1호
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• pp.38-47
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• 1995

이 연구에서는 삼척탄전 내에 위치하는 폐탄광인 동해탄광을 대상으로 산성 광산폐수의 중화 처리를 위한 각종 기초자료를 제시하고자 하였다. 산성 광산폐수의 측정시기에 따른 변화양상을 관찰한 결과 갈 수기에는 각종 잠재적 유독성 원소들의 함량이 증가하며, pH가 하락하여 수질이 악화되는 경향을 보였다. 공업용 소석회는 처리효율 및 경제성을 고려할 경우 산성 광산폐수의 처리를 위한 최적의 중화제로 판단되며, 평형 모델링 결과 중화처리과정에서 Fe는 FeOOH의 형태로, Al은 Al(OH)$_3$, 의 형태로 침전되는 것으로 추정된다. GIS를 이용하여 동해탄광일대 산성 광산폐수 처리시설의 위치를 제시하였으며 수문학적 자료를 이용하여 최대강우량 및 첨두유량을 계산하였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.206-209
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• 2001

This study presents the leaching characterization of heavy metals according to changes of pH by ANC test on slag produced in electric arc furnace, bottom ash produced in coal-fired plants and their recycling products. Availability test was performed to assess the fraction of the total concentration that under worst environmental conditions could become available for leaching. TCLP, KLT(Korea Leaching Test) and KLTS(Korea Leaching Test of Soil contamination) were carried out to compare the leaching capacity and to estimate the adequacy of regulatory leaching test. Results from regulatory leaching tests could be misleading because the variable ANC of wastes can lead to very different final leachate pHs. The final pH of the regulatory test is not the ambient pH in the disposal environment, the actual solubilities of contaminants in the field may be entirely different from those predicted by these regulatory tests. Leaching behaviour of by-products was changed by recycling processes, therefore acid neutralization capacity and availability of new products, not leaching concentration by one batch regulatory test, are necessary to determine the method of recycling.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.142-152
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• 2014

In this study, generic characteristics of the acid mine drainage (AMD), removal efficiency of iron, aluminium and manganese by chemical treatment, electrolysis and hybrid process using electrolysis after neutralization were evaluated. The pH of AMD was inversely proportional to the rainfall. In dry-season, the average pH of AMD was ranged from 4.5 to 5.5, showing slight variation. However, the pH of AMD was gradually decreased along with rainfall and dropped to 3.02 in September showing the greatest rainfall. Removal efficiency of heavy metals by chemical treatments using three different neutralizing agents or by electrolysis was low. However, a hybrid process performed with electrolysis after addition of neutralization shows higher removal capacity for heavy metal ions than neutralization-alone and electrolysisalone process.

• 한국재료학회지
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• 제22권5호
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• pp.227-236
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• 2012

Ionomer is a thermoplastic that is composed of covalent bonds and ionic bonds. It is possible to use this material in processes such as injection molding or extrusion molding due to the material's high oil resistance, weatherproof characteristics, and shock resistance. In this study, a new ionomer having a multifunctional group was prepared by a stepwise neutralization system with the addition of acidic and salt additives. In step I, to increase the contents of the multifunctional group and the acid degree in ethylene acrylic acid (EAA), MGA was added to the ionomer resin (EAA). A new ionomer was prepared via the traditional preparation method of the ionic cross-linking process. In step II, metal salt was added to the mixture of EAA and MGA. The extrusion process was performed using a twin extruder (L/D = 40, size : ${\varphi}30$). Ionomer film was prepared for evaluation of gas permeability by using the compression molding process. The degree of neutralized and ionic cross-linked new ionomer was confirmed by FT-IR and XRD analysis. In order to estimate the neutralization of the new ionomer film, various properties such as gas permeation and mechanical properties were measured. The physical strength and anti-scratch property of the new ionomer were improved with increase of the neutralization degree. The gas barrier property of the new ionomer was improved through the introduction of an ionic site. Also, the ionic degree of cross-linking and gas barrier property of the ionomer membrane prepared by stepwise neutralization were increased.