• Title, Summary, Keyword: Sulfuric Acid

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Effects of Simulated Sulfuric and Nitric Acid Rain on Growth and Seed Germination of Arabidopsis thaliana (인공 황산비 및 질산비가 애기장대의 생장과 종자발아에 미치는 영향)

  • 이석찬;박정안;박종범
    • Journal of Environmental Science International
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    • v.12 no.6
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    • pp.659-664
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    • 2003
  • The experiment was carried out to investigate the effects of sulfuric acid and nitric acid among the main components of simulated acid rain (SAR) on the growth of vegetative organs and seed germination of Arabidopsis thaliana. The Arabidopsis treated with SAR supplemented with sulfuric and nitric acids, respectively, showed 28% and 30% decrease of shoot and root growth compared to the control plants, and also many necrotic spots on leaf surfaces after SAR treatment were observed. The shoot and root length for plants grown with nitric acid rain was 14% and 17% lower, respectively, compared to the control, whereas those grown with sulfuric acid rain was 24% and 25% lower than control plants. When Arabidopsis seeds were sown in distilled water, germination rate was 100% after 7 days. However, 80% in SAR medium supplemented with sulfuric and nitric acids, 88% in sulfuric acid rain medium and 93% in nitric acid rain medium. The germination abilities of seeds harvested from SAR supplemented with sulfuric and nitric acids, sulfuric acid rain, and nitric acid rain were 73%, 73% and 94%, respectively. Consequently, sulfuric acids showed more inhibitory effects than nitric acids on the growth of vegetative organs as well as germination rates in Arabidopsis.

PUMP DESIGN AND COMPUTATIONAL FLUID DYNAMIC ANALYSIS FOR HIGH TEMPERATURE SULFURIC ACID TRANSFER SYSTEM

  • Choi, Jung-Sik;Shin, Young-Joon;Lee, Ki-Young;Yun, Yong-Sup;Choi, Jae-Hyuk
    • Nuclear Engineering and Technology
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    • v.46 no.3
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    • pp.363-372
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    • 2014
  • In this study, we proposed a newly designed sulfuric acid transfer system for the sulfur-iodine (SI) thermochemical cycle. The proposed sulfuric acid transfer system was evaluated using a computational fluid dynamics (CFD) analysis for investigating thermodynamic/hydrodynamic characteristics and material properties. This analysis was conducted to obtain reliable continuous operation parameters; in particular, a thermal analysis was performed on the bellows box and bellows at amplitudes and various frequencies (0.1, 0.5, and 1.0 Hz). However, the high temperatures and strongly corrosive operating conditions of the current sulfuric acid system present challenges with respect to the structural materials of the transfer system. To resolve this issue, we designed a novel transfer system using polytetrafluoroethylene (PTFE, $Teflon^{(R)}$) as a bellows material for the transfer of sulfuric acid. We also carried out a CFD analysis of the design. The CFD results indicated that the maximum applicable temperature of PTFE is about 533 K ($260^{\circ}C$), even though its melting point is around 600 K. This result implies that the PTFE is a potential material for the sulfuric acid transfer system. The CFD simulations also confirmed that the sulfuric acid transfer system was designed properly for this particular investigation.

Service Life Prediction of Concrete Structures Exposed to a Sulfuric Acid Environment

  • Jeon, Joong-Kyu;Moon, Han-Young;Jeon, Chan-Ki;Song, Jong-Hwa
    • Journal of the Korea Concrete Institute
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    • v.19 no.3
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    • pp.385-389
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    • 2007
  • In this study, it was investigated the resistance of OPC, 60% GGBS, 20% PFA and 10% SF mortar specimens against sulfuric acid corrosion. As an index for degree of acid corrosion, the corrosion depth was evaluated. Then, it was found that an increase in the duration of immersion and a decrease in the pH, as expected, resulted in a more severe corrosion irrespective of binders; 60% GGBS mortar specimen was the most resistant to sulfuric acid corrosion. From the laboratory testing of sulfuric acid corrosion, an empirical prediction model was suggested as a power function of time and the pH of sulfuric acid, and was applied to an assessment of concrete structures exposed to an acidic environment. It was found that the empirical model gave a more precise prediction of sulfuric acid deterioration of concrete rather than a conventional model, mostly used for predicting carbonation of concrete.

Production of Sulfuric Acid and Ammonia Water from Ammonium Sulfate Using Electrodialysis with Bipolar Membrane and Ammonia Stripping

  • Yeon Kyeong-Ho;Song Jung-Hoon;Shim Bong-Sup;Moon Seung-Hyeon
    • Korean Membrane Journal
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    • v.7 no.1
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    • pp.28-33
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    • 2005
  • The feasibility of producing sulfuric acid and ammonia water from ammonium sulfate was investigated by an integrated process including ammonia stripping (AS) and electrodialysis with bipolar membrane (EDBM). It was suggested that the production of sulfuric acid using ammonia stripping-electrodialysis with bipolar membrane (ASEDBM) was effective in obtaining high concentration of sulfuric acid compared with EDBM alone. AS was carried out over pH 11 and within the range of temperatures, $20^{\circ}C{\~}60^{\circ}C$. Sodium sulfate obtained using AS was used as the feed solution of EDBM. The recovery of ammonia increased from $40\%$ to $80\%$ at $60^{\circ}C$ due to the increased mobility of ammonium ion. A pilot-scale EDBM system, which is composed of two compartments and 10 cell pairs with an effective membrane area of $200 cm^2$ per cell, was used for the recovery of sulfuric acid. The performance was examined in the range of 0.1 M${\~}$1.0 M concentration of concentrate compartment and of $25 mA/cm^2{\~}62.5 mA/cm^2$ of current density. The maximum current efficiency of $64.9\%$ was obtained at 0.1 M sulfuric acid because the diffusion rate at the anion exchange membrane decreased as the sulfuric acid of the concentrate compartment decreased. It was possible to obtain the 2.5 M of sulfuric acid in the $62.5 mA/cm^2$ with a power consumption of 13.0 kWh/ton, while the concentration of sulfuric acid was proportional to the current density below the limiting current density (LCD). Thus, the integrating process of AS-EDBM enables to recover sulfuric acid from the wastewaters containing ammonium sulfate.

Reaction of the System of Coal Fly Ash-Sulfuric Acid-Calcium Hydroxide (플라이 애쉬-황산-수한화칼슘계의 반응)

  • 송종택;안민선;정문영
    • Journal of the Korean Ceramic Society
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    • v.33 no.12
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    • pp.1331-1338
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    • 1996
  • In order to investigate the reaction in the system of fly ash-sulfuric acid-calcium hydroxide the hydrates were produced by the addition of Ca(OH)2 to fly ash activated with sulfuric acid at various temperatures. And then they were characterized by XRD. SEM and TG-DTA. It was found that in the reaction of fly ash with sulfuric acid fly ash was not decomposed but Al2O3 and SiO2 component in it were activated. The addition of calcium hydroxide into this system resulted in the formation of ettringite and calcium silicate hydrate (C-S-H) As the concentration of sulfuric acid and reaction temperature increased the amount of calcium hydroxide decreased fast. At this time gypsum produced by the reaction calcium hydroxide with sulfuric acid was consumed to form ettringite. Accordingly the formation of ettringite increased with calcium hydroxide and reaction time. And it showed faster than the formation of C-S-H.

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Separation of Sulfuric Acid from Sulfuric Acid/Glucose Solution by Electrodialysis (황산/글루코스 용액으로부터 전기투석에 의한 황산 분리)

  • Lee, Se-Hoon;Kim, Young-Sook;Chu, Cheun-Ho;Na, Il-Chai;Oh, Yong-Hwan;Park, Kwon-Pil
    • Korean Chemical Engineering Research
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    • v.55 no.1
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    • pp.7-12
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    • 2017
  • Recovery of sulfuric acid is very important after biomass converted to sugar by acid hydrolysis. In this work, the separation of sulfuric acid from sulfuric acid/glucose solution was studied by electrodiaysis. Three chamber method, which requires both anion membrane and cation membrane, is the most commonly used in the electrodialysis process, but two chamber method using only an anion membrane was the focus of this study. Sulfuric acid was perfectly separated from a mixture of 10~30 wt% glucose and 1~3 M sulfuric acid by electrodialysis using two chamber method. The separation rate of sulfuric acid lineary increased with higher current density when the affect of diffusion and convection of the membrane was small. Without electric energy, 45% of sulfuric acid was separated by diffusion and convection only.

Studies on Slip and Mechanical Properties of Thermoplastic Polyurethane Elastomer Containing Sulfuric Acid (Sulfuric acid를 도입한 열가소성 폴리우레탄 탄성체의 슬립특성 및 기계적 물성에 관한 연구)

  • Mok, Dong Youb;Shin, Hyun Deung;Kim, Dong Ho;Kim, Gu Ni;Kim, In-Soo
    • Elastomers and Composites
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    • v.48 no.4
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    • pp.256-262
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    • 2013
  • We synthesized thermoplastic polyurethane elastomer (TPU) with different contents of sulfuric acid group, and characterized their physical properties such as mechanical, thermal and grip properties. And the results were compared with carboxylic acid-introduced TPU. Wet slip, tensile strength and abrasion properties were increased by the introduction of acid group. Mechanical properties increased with increasing the acid content up to 0.3 wt%. However, wet slip was continually increased as the acid content increased due to increase of hydrophilicity of TPU.

The Elution effects by Sulfuric acid in the EAF dust (황산용액에 의한 제강분진 중 중금속의 용출효과)

  • Jeong, Rae-Youn;Lee, Hyun-Pyo;Lee, Jin-Hui
    • Journal of the Korean Applied Science and Technology
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    • v.27 no.4
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    • pp.475-481
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    • 2010
  • Elution effect was studied by the reactions between Electric arc furnace(EAF)dust and conc. or dil. sulfuric acid for the purpose of recoverying of the useful metals afterwards. The methods of mixing with acids and EAF dust for the elutions were depend on the ratios of acid/EAF dust. Experimental results showed that increased the ratios of sulfuric acids, decreased the elution effects are on the Zn, Fe and Mn, and conc. sulfuric acid showed higher elution effects than dil. sulfuric acids for the all metals. But in case of Pb, dil. sulfuric acid showed higher elution effects than conc. sulfuric acids conversely. Furthermore, the reason of the extreamly low quantities of eluted Pb is caused by the low solubilities by sulfuric acids compared to the other metals, as the results of the insoluble Pb is removed by the process of filtering.

Determination of Iodide in Sulfuric Acid Aqueous Solution by the Ion Chromatography with UV Detection (이온 크로마토그래피와 자외선 검출을 이용한 황산수용액 중의 요오드 음이온 정량)

  • Park, Yang-Soon
    • Analytical Science and Technology
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    • v.14 no.4
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    • pp.306-310
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    • 2001
  • Ion chromatography was applied to determine iodide remained in sulfuric acid aqueous solution after adsorption procedure. Iodide was determined in 0.25 M, 0.5 M and 1 M sulfuric acid solution on time variation. Because sulfuric acid in solution plays as an oxidizer, the concentration of iodide decreased with increasing concentration or sulfuric acid. Thereafter, sulfuric acid was neutralized with sodium hydroxide. Good linearity(r=0.99999) was obtained at the range of 0-20 mg/L 1 in 0.5 M sodium sulfate matrix.

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Effects of Aerosol Hygroscopicity on Fine Particle Mass Concentration and Light Extinction Coefficient at Seoul and Gosan in Korea

  • Choi, Eun-Kyung;Kim, Yong-Pyo
    • Asian Journal of Atmospheric Environment
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    • v.4 no.1
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    • pp.55-61
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    • 2010
  • The sensitivity of aerosol light extinction coefficient to the aerosol chemical composition change is estimated by (1) calculating the aerosol water content and chemical concentrations by a gas/particle equilibrium model and (2) calculating the aerosol light extinction coefficient by a Mie theory based optical model. The major chemical species are total (gas and particle phase) sulfuric acid, total nitric acid, and total ammonia which are based on the measurement data at Seoul and Gosan. At Seoul, since there were enough ammonia to neutralize both total sulfuric acid and total nitric acid, the dry ionic concentration is most sensitive to the variation of the total nitric acid level, while the total mass concentration (ionic concentration plus water content) and thus, the aerosol light extinction coefficient are primarily determined by the total sulfuric acid. At Gosan, since the concentration of ambient sulfuric acid was the highest among the inorganic species, sulfate salts determined aerosol hygroscopicity. Thus, both ionic and total mass concentration, and resultant aerosol light extinction coefficient are primarily determined by the sulfuric acid level.