• Title, Summary, Keyword: humic acid

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Humic Acid Removal from Water by Iron-coated Sand: A Column Experiment

  • Kim, Hyon-Chong;Park, Seong-Jik;Lee, Chang-Gu;Han, Yong-Un;Park, Jeong-Ann;Kim, Song-Bae
    • Environmental Engineering Research
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    • v.14 no.1
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    • pp.41-47
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    • 2009
  • Column experiments were performed in this study to investigate humic acid adhesion to iron oxide-coated sand (ICS) under different experimental conditions including influent humic acid concentration, flow rate, solution pH, and ionic strength/composition. Breakthrough curves of humic acid were obtained by monitoring effluents, and then column capacity for humic acid adsorption ($C_cap$), total adsorption percent (R), and mass of humic acid adsorbed per unit mass of filter media ($q_a$) were quantified from these curves. Results showed that humic acid adhesion was about seven times higher in ICS than in quartz sand at given experimental conditions. This indicates that humic acid removal can be enhanced through the surface charge modification of quartz sand with iron oxide coating. The adhesion of humic acid in ICS was influenced by influent humic acid concentration. $C_cap$ and $q_a$ increased while R decreased with increasing influent humic acid concentration in ICS column. However, the influence of flow rate was not eminent in our experimental conditions. The humic acid adhesion was enhanced with increasing salt concentration of solution. $C_cap$, $q_a$ and R increased in ICS column with increasing salt concentration. On the adhesion of humic acid, the impact of CaCl2 was greater than that of NaCl. Also, the humic acid adhesion to ICS decreased with increasing solution pH. $C_cap$, $q_a$ and R decreased with increasing solution pH. This study demonstrates that humic acid concentration, salt concentration/composition, and solution pH should be controlled carefully in order to improve the ICS column performance for humic acid removal from water.

Toxicological Studies on the Humic acid (Humic acid의 독성학적 연구)

  • 라규환
    • Environmental health and toxicology
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    • v.2 no.1_2
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    • pp.13-16
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    • 1987
  • The author obtained three kinds of humic acid from the soil of suburbs in the Wonju city, sediments of Wonju stream and Maeji reservoir in 29 April 1986. The yield of each humic acid was 7.23 g, 3.35 g and 4.61 g per sample 200 g. In the physicochemical characters, the COD varied from 65.9 ppm to 54.9 ppm and BOD showed 6.7~15.9 ppm, but the standard humic acid was COD 58.9 ppm and BOD 6.5 ppm in 0.01 % solution. Doses of the humic acids for 20% methemoglobin formation are as follows; 0.303 mg/m$\ell$ in St. A humic acid, 0.602 mg/m$\ell$ in St. B humic acid, 0.84 mg/m$\ell$ in St. C humic acid and 0.105 mg/m$\ell$ in standard humic acid.

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Effect of Humic acid on the Distribution of the Contaminants with Black Shale (휴믹산이 black shale과 오염물질의 분포에 미치는 영향에 대한 연구)

  • Min, Jee-Eun;Park, Jae-Woo
    • Journal of Korean Society on Water Environment
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    • v.20 no.6
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    • pp.670-675
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    • 2004
  • Humic acids are macromolecules originated from natural water, soil, and sediment. The characteristics of humic acid enable it to change the distribution of metals as well as many kinds of organic contaminants and to determine the sorption of them from soil solution. To see the effect of humic acid on the removal rate of organic contaminants and heavy metals, batch-scale experiments were performed. As a natural geosorbent, black shale was used as a sorbent media, which showed hight sorption capacity of trichloroethylene (TCE), lead, cadmium and chromium. The effect of sorption-desorption, pH, ionic strength and the concentration of humic acid was taken into consideration. TCE sorption capacity by black shale was compared to natural bentonite and hexadecyltrimethylammonium (HDTMA) modified bentonite. The removal rate was good and humic acid also sorbed onto black shale very well. The organic part of humic acid could effectively enhance the partition of TCE and it act as an electron donor to reduce Cr(VI) to Cr(III). Cationic metal of Pb(II) and Cd(II) also removed from the water by black shale. With 3 mg/L of humic acid, both Pb(II) and Cd(II) were removed more than without humic acid. That could be explained by sorption and complexation with humic acid and that was possible when humic acid could change the hydrophobicity and solubility of heavy metals. Humic acid exhibited desorption-resistivity with black shale, which implied that black shale could be an alternative sorbent or material for remediation of organic contaminants and heavy metals.

A Study on the Coagulation of Aquatic Humic Acid and Reducing Residual Aluminum (수중 Humic Acid의 효율적 응집처리와 잔류알루미늄 감소방안에 관한 연구)

  • 김수연;정문호;두옥주
    • Journal of Environmental Health Sciences
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    • v.24 no.2
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    • pp.38-46
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    • 1998
  • The purpose of this study is to evaluate and compare the effective coagulation of commercial humic acid which is well known as major precursor of trihalomethane, with LAS and PAC and to quantify the residual aluminum in the treated water. Then the optimum pH, the dosage of coagulant were determined. 1. Humic acid concentrati6n, UV absorbance and color were well correlated and UV absorbance(254 nm) and color seem to be used in quntificative analysis of humic acid of same kind. 2. Optimal dosage of LAS and PAC increase as humic acid concentration increases. And optimal pH range for coagulation using LAS is pH 5.5-7.0 and pH 3.5-6.5 for PAC. Within these ranges the removal efficiency is 90-99%. 3. The results of quantification of residual aluminum in treated water shows that minimal aluminum remains on the optimal coagulation condition. But the residual aluminum increses as the dosage of coagulant is beyond the optimal range. Thus the dosage of coagulant should be chosen with the condition on which humic acid removal is maximum and the residual aluminum concentration is minimum. 4. In the water treatment process the raw water pH range is 6.5-8.0, and it seems to be possible to remove humic acid by charge neutralization not by sweep floc. But it should be considered that different commercial humic acids have different physical and chemical characteristics.

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Removal of Dissolved Humic Acid with Physicochemical Treatment Process (물리화학적 공정에 의한 용존성 Humic Acid의 제거)

  • Kim, Jong-Shik;Choi, Joon-Ho
    • Applied Chemistry for Engineering
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    • v.10 no.5
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    • pp.737-742
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    • 1999
  • This study was conducted for the two purposes; one was removal of dissolved humic acid, the well-known precursor of trihalomethanes (THMs), by physicochemical treatment processes such as ozone oxidation, coagulation and activated carbon adsorption. The other was qualitative identification of by-products in chlorination of the dissolved humic acid. When ozone oxidation was applied to remove the dissolved humic acid, pH was abruptly decreased. It was indicated that humic acid was not perfectly converted to $CO_2$ and $H_2O$, but to low fatty acid. In coagulation process, the coagulant was polyaluminumchloride which was widely used for drinking water treatment in recent years. With the dosage of 160 mg/L, total organic carbon(TOC), $COD_{Cr}$ and color were removed with 23%, 24% and 5% respectively. Color was effectively removed by ozone oxidation process, which was the first order reaction, with the reaction rate constant of $0.067min^{-1}$. In activated carbon adsorption process, preozonation process could remove more effectively the dissolved humic acid than that without preozonation. When the dissolved humic acid and sodium hydrochloride were reacted with 1 mg-NaOCl/mg-TOC, only trihalomethanes were detected.

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Application of Ferrate(VI) to the Removal of Humic Acid and Heavy Metals (Cu, Mn, and Zn) (Humic Acid와 중금속(Cu, Mn, Zn)제거를 위한 Ferrate(VI)의 적용)

  • Lim, Mi-Hee;Kim, Myoung-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.6
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    • pp.454-459
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    • 2009
  • In this paper, we have performed an experimental study to simultaneously remove humic acid (RA) and heavy metals (Cu, Mn, and Zn) from the river water using potassium ferrate(VI), a multi-purpose and environment-friendly chemical. In the experiments for treating three 0.1 mM single heavy metals using 0.03${\sim}$0.7 mM (as Fe) ferrate, the removal efficiencies ranged 28${\sim}$99% for Cu, 22${\sim}$73% for Mn, and 18${\sim}$100% for Zn. In addition, humic acid and heavy metals could be very efficiently removed at the same time using 0.03${\sim}$0.7 mM (as Fe) ferrate: for example, 49${\sim}$81% (humic acid), 93${\sim}$100% (Cu), 22${\sim}$86% (Mn), and 20${\sim}$100% (Zn). The removal efficiencies of humic acid and heavy metals in the mixture of humic acid and heavy metals were higher than that in the solution of single humic acid or heavy metal. It can be explained by the fact that, before adding ferrate to the mixed solution, part of solutes were already removed by the complexation between the negatively-charged functional groups of humic acid and heavy metal cations.

Isolation and Characterization of Aquatic Humic Acid and Fulvic Acid (수질계의 Humic Acid와 Fulvic Acid의 분리 및 특성)

  • Rhee, Dong Seok
    • Analytical Science and Technology
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    • v.15 no.1
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    • pp.36-42
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    • 2002
  • The dissolved organic carbon extracted from groundwater is separated into humic acid and fulvic acid. They are characterized for their chemical composition, spectroscopic characteristics using UV/VIS, IR and solid state $^{13}C-NMR$ spectroscopy, proton exchange capacity and molecular size distribution. The results are comparable with the literature data. The study explains that the aquatic humic and fulvic acid in this experiment are site-specipic and polydisperse natural organic matter with considerable proton exchange capacity.

Cd으로 오염된 토양의 EK 정화시 Humic acid가 미치는 영향

  • 구한모;김정환;한상재;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.131-134
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    • 2001
  • This research was carried out to evaluate the effects of humic acid on contaminated kaoline with cadmium when electrokinetic remediation. Electrokinetic remediation test was performed depending on humic acid concentrations(0.005, 0.01, 0.05, 0.083, 0.1, 0.5, 5.0mg/g) in contaminated kaoline with cadmium and time(4, 8, 12days). In the absence of humic acid, Cd at the anode showed the highest concentration while Cd concentrations were lower as the concentration of humic acid increased. The removal of Cd to the anode reservoir was increased with increasing humic acid concentration by electroosmosis or ion migration.

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Effects of Polyelectrolyte Dosage, Kaoline Particles and pH on Flocculation of Humic Acid by Catonic Polyelectrolytes

  • Kam, Sang-Kyu;Kim, Dae-Kyoung;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.12 no.8
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    • pp.861-870
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    • 2003
  • Using a simple continuous optical technique, coupled with measurements of zeta potential, the effects of polyelectrolyte dosage, kaoline particles and pH on flocculation of humic acid by several cationic polyelectrolytes, have been examined. The charge density of a polyelectolyte is important in determining the optimum dosage and in the removal of humic acid. The optimum dosage is less for the polyelectrolytes of higher charge density and is the same regardless of the presence of kaoline particles of different turbidity. At the dosage, the removal of humic acid is higher for the polyelectrolytes of higher charge density and the zeta potential of humic acid approaches to near zero, With increasing pH of humic acid, the optimum dosage increases and the flocculation index value obtained at the dosage decreases in the following pH 7 > pH 5 > pH 9, regardless of polyelectrolytes.

Retrospect on Refractories in Water Treatment (기존 정수처리방법으로 제거가 어려운 유기물에 대한 실험적 연구)

  • 우달식;남상호
    • Journal of Environmental Health Sciences
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    • v.21 no.4
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    • pp.17-23
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    • 1995
  • As a basic experiment to develope biological pretreatment proces~ in water treatment, the experiments on biodegradability and isothermal adsorption of activated carbon were performed on refractories such as humic acid, $NH_3-N$, phenol and ABS which caused the problems in drinking water treatment. Also, the treatabilities on humic acid were examined in the continuous flow type reactors. The removal efficiencies of humic acid, $NH_3-N$, phenol and ABS in the biodegradable experiments for 5 days were 20.1%, 73.4%, 91.7% and 97.5%, respectively. In the isothermal adsorption test of refractories on activated carbon to be used as a media in the continuous flow type reactors, ABS and phenol are adsorbed easily, but humic acid and $NH_3-N$ are difficult to be done. The removal efficiencies of humic acid in granular activated carbon(GAC) reactor were about 7-8% higher than in biological activated carbon(BAC) reactor. The removal efficiencies of humic acid in biological fluidized bed(BFB) reactor were about 30% in GAC media, but were almost zero in sea sand media.

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