• Title/Summary/Keyword: Isotherm adsorption

Search Result 899, Processing Time 0.026 seconds

하수슬러지의 토양개량재 적용시 유기인계 농약의 흡착능력에 관한 연구

  • 임은진;이재영
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2004.04a
    • /
    • pp.125-130
    • /
    • 2004
  • This study has been assessed the influence of applying sewage sludge to soil amendments on the sorption properties, and leaching potential of three commonly used organophosphorus pesticides, Diazinon, Fenitrothion, and Chlorpyrifos. A sandy soil with a low content of organic carbon was treated with sewage sludge with a ratio sandy soil : sludge ratio of 30:1. The sorption was determined with the batch equilibrium technique. The sorption isotherms could be described by Freundlich equation. The Freundlich constant, K value which measures sorption capacity, were 3.97, 9.94, 22.48 for Diazinon, Fenitrothion, Chlorpyrifos in non-amended soil. But in amended soil, K value was 12.58, 28.47, and 61.21 for Diazinon, Fenitrothion, and Chlorpyrifos. The overall effect of sewage sludge addition to soil was to increase pesticides adsorption, due to the high sorption capacity of the organic matter. The effect of sludge on tile leaching of pesticides in the soil was studied using packed soil columns. Total recoveries of pesticides in soil and leachate with leaching in soil column, were in the range of about 73~84%, was reduced with the passage of time. Diazinon moved more rapidly than Chlorpyrifos in the unamended soil due to greater sorption and lower water solubility of Chlorpyrifos. Total amounts of pesticides leached from the sewage sludge amended soils were significantly reduced when compared with unamended soils. This reduction may be mainly due to and increase in sorption in amended soils, as a consequence of the increase in the organic matter content.

  • PDF

Effect of oxyfluorination on activated electrospun carbon nanofibers for $CO_2$ storage (함산소불소화 효과에 의한 전기방사 활성탄소나노섬유의 $CO_2$ 저장)

  • Bai, Byong Chol;Kim, Jong Gu;Im, Ji Sun;Lee, Young-Seak
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.219.2-219.2
    • /
    • 2011
  • The oxyfluorination effects of electrospun carbon nanofibers (OFACFs) were investigated for $CO_2$ storage. Carbon nanofibers were prepared form poly acrylonitrile / N,N-dimethylformamide solution through electrospinning method and heat treatment. Chemical activation of carbon nanofibers were carried out in order to improve the pore structure. And the surface modification of activated carbon nanofibers was conducted by oxyfluorination to improve the $CO_2$ storage on effect of introduced functional groups. The samples were labeled CF (electrospun carbon nanofiber), ACF (activated carbon nanofibers), OFACF-1 ($F_2:O_2$ = 3:7), OFACF-2 ($F_2:O_2$ = 5:5) and OFACF-3 ($F_2:O_2$ = 7:3). The functional group of OFACFs was investigated by x-ray photoelectron spectroscopy analysis. The specific surface area, pore volume and pore size of OFACFs were calculated and pore shape was estimated by the BET equation. Through the adsorption isotherm, the specific surface area and pore volume significantly decreased by oxyfluorination.

  • PDF

Phosphate Removal of Aqueous Solutions using Industrial Wastes (산업폐기물을 이용한 수용액 중 인산염의 흡착 제거)

  • Kang, Ku;Kim, Young-Kee;Park, Seong-Jik
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.1
    • /
    • pp.49-57
    • /
    • 2013
  • The present study was conducted to investigate phosphate removal from aqueous solution using industrial wastes, red mud (RM), acid treated red mud (ATRM) and converter furnace steel slag (CFSS). The chemical composition of adsorbents was analyzed using X-ray fluorescence (XRF). Batch experiments and elution experiments using water tank were performed to examine environmental factors that influences on phosphate removal. Kinetic sorption data of RM, ATRM, and CFSS were described well by the pseudo second-order kinetic sorption model, and equilibrium sorption data of all adsorbents obeyed Freundlich isotherm model. The adsorption capacities of adsorbents followed order: ATRM (7.06 mg/g)>RM (4.34 mg/g)>CFSS (1.88 mg/g). Increasing pH from 3 to 11, the amount of adsorbed phosphate on all RM, ATRM, and CFSS were decreased. The presence of sulfate and carbonate decreased the phosphate removal of RM and ATRM but did not influence on the performance of CFSS. The phosphate removal of RM, ATRM, and CFSS was greater in seawater than deionized water, resulting from the presence of cations in seawater. The water tank elution experiments showed that RM capping blocked the elution of phosphate effectively. It was concluded that the adsorbents can be successfully used for the removal of the phosphate from the aqueous solutions.

Sorption of chlorophenols on geotextile of the geosynthetic clay liners

  • Ahari, M'hamed;Touze-Foltz, Nathalie;Mazeas, Laurent
    • Environmental Engineering Research
    • /
    • v.25 no.2
    • /
    • pp.163-170
    • /
    • 2020
  • Knowledge of organic micropollutant transfers in barrier seal materials from waste storage facilities is limited to volatile organic compounds and phenolic compounds at ambient temperature. This study focused on the sorption of chlorophenols (CPs) from various geotextiles from clay geosynthetics under the influence of temperature. Also to study the impact of the polarity or the amount of CPs adsorbed on geotextiles with the partition coefficient. The effect of various parameters such as contact time, effect of temperature, initial CPs concentration and adsorbent dosage has been carried out in this study. The result obtained is non-linear and the data was calculated for affinity with Freundlich isotherm model. An important observation is that the amount of CPs sorbed on geotextiles increases with a growing number of chlorine atoms, ie increases with the partition coefficient (log Kow). During this study, a decrease in adsorbent properties was observed with the rise in temperature from 23℃ to 55℃. The partitioning coefficients for CPs examined range are from 2.4 (R2 = 0.86) to 8.4 mL/g (R2 = 0.90). Among the CPs studied, the highest adsorbed quantity was observed for pentachlorophenol with 0.052 g/g at 23℃, this quantity will decrease with the increase in temperature.

Dyeability and Functionality of Catechu(Part II) -Dyeing Properties of Protein Fiber with Catechu- (아선약의 염색성과 기능성(제2보) -단백질섬유에 대한 염색성-)

  • Nam, Ki-Yeon;Lee, Jung-Soon
    • Korean Journal of Human Ecology
    • /
    • v.19 no.4
    • /
    • pp.709-717
    • /
    • 2010
  • This study investigated the properties and functions of wool and silk dyed with Catechu by examining the effects of dying conditions such as dye concentration, dying temperature, dyeing time, pH level and pre-mordants. These conditions were examined in relation to dye uptake and color changes, washing fastness, light fastness, ultraviolet-cut ability and antimicrobial ability of the dyed fabrics. Catechu showed good affinity to silk fiber. Langmuir adsorption isotherm was obtained, and so it was considered that ionic bondings are formed between Catechu and protein fiber. As the dyeing time and temperature is increased, the dyeability of both silk and wool fabrics also increases. At high temperatures the color of dyed fabrics changes from Y and YR to R. Wool is effective in using Al, Cu, Fe mordant, while silk is effective only in using only Cu mordants. The dyeability was shown to be improved at low pH levels. Additionally, both washing fastness and light fastness were shown to be low. However, the fabric color gradually changed to red was due to mailard reaction of catechol tannin causingby repeated washing and sunlight. The ultraviolet-cut ability was improved for cotton fabric dyed with Catechu. Also, dyed fabric with Catechu showed very good antimicrobial abilities at 99.9%.

Sorption of copper ion on waste pig bone (돼지 폐(廢) 골분(骨粉)에 의한 구리이온 흡착(吸着))

  • Kim, Eun-Jung;Woo, Sung-Hoon;Park, Seung-Cho
    • Resources Recycling
    • /
    • v.15 no.2 s.70
    • /
    • pp.45-49
    • /
    • 2006
  • The removal of copper ion from aqueous solution by adsorption with bone char that made from spent pig bone has been studied. This paper was studied the effects of bone char dosage and pH. The optimal results show that bone char adsorbs about 96.5 percent of copper ion in aqueous solution containing 50 mg/L as initial concentration at pH 5.0 when the bone char of 5g/L is used for 30 hours. Increase in the initial pH of the copper solution resulted in an increase in the copper ion uptake per weight of the sorbent Freundlich isotherm model was found to be applicable for the experimental data of $Cu^{2+}$.

A Simulation Study on the Removal Process of the Heavy Metal Ion in Aqueous Solution by the Functionalized Silica Beads (기능화된 실리카 비드를 이용한 수용액상의 중금속 이온의 제거공정에 대한 모사 연구)

  • Woo, Yoon-Hwan;Choo, Chang-Upp
    • Clean Technology
    • /
    • v.17 no.2
    • /
    • pp.150-155
    • /
    • 2011
  • The removal process of heavy metal ion in aqueous solution by the functionalized silica bead was simulated using the finite difference method. Equilibrium model and non-equilibrium model were proposed and the effects of dimensionless groups and various parameters were investigated. Freundlich isotherm was used in equilibrium model and 1st order adsorption rate expression was assumed in non-equilibrium model. The comparison results by the predictions of equilibrium and non-equilibrium models showed good agreement. The predictions of equilibrium model were compared with experimental results reported in literature and showed the marginal agreement.

Removal Efficiency of the Pollutants from Piggery Wastes with Activated Carbon Treated with Metal and Their Pilot Scale Design

  • Oh, Won-Chun;Park, Chong-Sung;Bae, Jang-Soon;Ko, Young-Shin
    • Carbon letters
    • /
    • v.7 no.3
    • /
    • pp.180-187
    • /
    • 2006
  • The treatment of piggery wastes was carried out at pilot scale using a multilayered metal-activated carbon system followed by carbon bed filtration. The physicochemical properties were obtained from treated samples with aqueous solutions containing metallic ions such as $Ag^+$, $Cu^{2+}$, $Na^+$, $K^+$ and $Mn^{2+}$, which main obsevations are subjected to inspect surface properties, color removal properties by Uv/Vis and EDX. Multilayered metal-activated carbons were contacted with waste water to investigation of the simultaneous catalytic effect for the COD, BOD, T-N and T-P removal. The removal results for the piggery waste using multilayered metal-activated carbon bed was achieved the satisfactory removal performance under permitted values of Ministry of Environment of Korea. The high efficiency of the multilayered metal-activated carbon bed was determined by the performance of this material for trapping, catalytic effect and adsorption of organic solid particles.

  • PDF

SBA-15 Supported Fe, Ni, Fe-Ni Bimetallic Catalysts for Wet Oxidation of Bisphenol-A

  • Mayani, Suranjana V.;Mayani, Vishal J.;Kim, Sang Wook
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.12
    • /
    • pp.3535-3541
    • /
    • 2014
  • Bisphenol A is considered as pollutant, because it is toxic and hazardous to living organisms even at very low concentrations. Biological oxidation used for removing this organic from waste water is not suitable and consequently application of catalytic wet oxidation has been considered as one of the best options for treating bisphenol A. We have developed Fe/SBA-15, Ni/SBA-15 and Fe-Ni/SBA-15 as heterogeneous catalysts using the advanced impregnation method for oxidation of bisphenol A in water. The catalysts were characterized with physico-chemical characterization methods such as, powder X-ray diffraction (PXRD), FT-IR measurements, N2 adsorption-desorption isotherm, thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis. This work illustrates activity of the catalysts for heterogeneous catalytic degradation reaction revealed with excellent conversion and recyclability. The degradation products identified were not persistent pollutants. GC-MS analysis identified the products: 2,4-hexadienedioic acid, 2,4-pentadienic acid and isopropanol or acetic acid. The leachability study indicated that the catalysts release very little metals to water. Therefore, the possibility of water contamination through metal leaching was almost negligible.

Development of a Mathematical Model for Simulating Removal Mechanisms of Heavy Metals using Biocarrier Beads (미생물 담체를 이용한 납 제거기작 모의를 위한 수학적 모델의 개발)

  • Seo, Hanna;Lee, Minhee;Wang, Sookyun
    • Journal of Soil and Groundwater Environment
    • /
    • v.18 no.4
    • /
    • pp.8-18
    • /
    • 2013
  • Biocarrier beads with dead biomass, Bacillus drentensis, immobilized in polymer polysulfone were synthesized to remove heavy metals from wastewater. To identify the sorption mechanisms and theoretical nature of underlying processes, a series of batch experiments were carried out and a mathematical model was developed to quantify the biosorption of Pb(II) by the biocarrier beads. A series of mass balance equations for representing mass transfer of metal sorbents in biocarrier beads and surrounding solution were established. Major model parameters such as external mass transfer coefficient and maximum sorption capacity, etc. were determined from pseudo-first-order kinetic models and Langmuir isotherm model based on kinetic and equilibrium experimental measurements. The model simulation displays reasonable representations of experimental data and implied that the proposed model can be applied to quantitative analysis on biosorption mechanisms by porous granular beads. The simulation results also confirms that the biosorption of heavy metal by the biocarrier beads largely depended on surface adsorption.