• Title/Summary/Keyword: kaolin

Search Result 511, Processing Time 0.079 seconds

Removal of Toxic Pollutants from Aqueous Solutions by Adsorption onto Organo-kaolin

  • Sayed Ahmed, S.A.
    • Carbon letters
    • /
    • v.10 no.4
    • /
    • pp.305-313
    • /
    • 2009
  • In this study, the adsorption of toxic pollutants onto cetyltrimethylammonium kaolin (CTAB-Kaolin) is investigated. The organo-kaolin is synthesized by exchanging cetyltrimethylammonium cations (CTAB) with inorganic ions on the surface of kaolin. The chemical analysis, the structural and textural properties of kaolin and CTAB-kaolin were investigated using elemental analysis, FTIR, SEM and adsorption of nitrogen at $-196^{\circ}C$. The kinetic adsorption and adsorption capacity of the organo-kaolin towards o-xylene, phenol and Cu(II) ion from aqueous solution was investigated. The kinetic adsorption data of o-xylene, phenol and Cu(II) are in agreement with a second order model. The equilibrium adsorption data were found to fit Langmuir equation. The uptake of o-xylene and phenol from their aqueous solution by kaolin, CTAB-kaolin and activated carbon proceed via physisorption. The removal of Cu(II) ion from water depends on the surface properties of the adsorbent. Onto kaolin, the Cu(II) ions are adsorbed through cation exchange with $Na^+$. For CTAB-kaolin, Cu(II) ions are mainly adsorbed via electrostatic attraction with the counter ions in the electric double layer ($Br^-$), via ion pairing, Cu(II) ions removal by the activated carbon is probably related to the carbon-oxygen groups particularly those of acid type. The adsorption capacities of CTAB-kaolin for the investigated adsorbates are considerably higher compared with those of unmodified kaolin. However, the adsorption capacities of the activated carbons are by far higher than those determined for CTAB-kaolin.

The Effects of Kaolin Addition on the Properties of Reticulated Porous Diatomite-kaolin Composites (고령토의 첨가가 3차원 망상 구조를 가지는 다공성 규조토-고령토 복합재의 기본 특성에 미치는 영향)

  • Lee, Chae-Young;Lee, Sujin;Ha, Jang-Hoon;Lee, Jongman;Song, In-Hyuck;Moon, Kyoung-Seok
    • Journal of Korean Powder Metallurgy Institute
    • /
    • v.27 no.4
    • /
    • pp.325-332
    • /
    • 2020
  • In this study, the effects of kaolin addition on the properties of reticulated porous diatomite-kaolin composites are investigated. A reticulated porous diatomite-kaolin composite is prepared using the replica template method. The microstructure and pore characteristics of the reticulated porous diatomite-kaolin composites are analyzed by controlling the PPI value (45, 60, and 80 PPI) of the polyurethane foam (which are used as the polymer template), the ball-milling time (8 and 24 h), and the amount of kaolin (0-50 wt. %). The average pore size decreases as the amount of kaolin increases in the reticulated porous diatomite-kaolin composite. As the amount of kaolin increases, it can be determined that the amount of inter-connected pore channels is reduced because the plate-shaped kaolin particles connect the gaps between irregular diatomite particles. Consequently, a higher kaolin percentage affects the overall mechanical properties by improving the pore channel connectivity. The effect of kaolin addition on the basic properties of the reticulated porous diatomite-kaolin composite is further discussed with characterization data such as pore size distribution, scanning electron microscopy images, and compressive strength.

Mullitization of HF-treated Kaolin (HF 처리된 Kaolin의 Mullite화 반응)

  • 박정현;장안재;박한수
    • Journal of the Korean Ceramic Society
    • /
    • v.24 no.4
    • /
    • pp.376-384
    • /
    • 1987
  • Kaolin was treated by HF and fired at high temperature in order to reduce silica and impurity minerals of kaolin, and eventually to increase the yield of mullite. The kaolin structure was destroyed by HF-treatment and transformed into mullite at lower temperature than those of non-treated kaolin. Not only the silica content of kaolin was reduced, but also the crystalline structure of it was destroyed by HF-treatment.

  • PDF

Fouling Characteristics in the Microfiltration of Mixed Particle Suspensions (혼합입자 용액의 정밀여과막 오염특성)

  • 정건용
    • Membrane Journal
    • /
    • v.11 no.4
    • /
    • pp.161-169
    • /
    • 2001
  • Single and mixed particle suspensions of kaolin, bentonite, starch and PMMA were carried out using a dead-end Amicon fi1tration cell with microfilteration membranes. The experimental data of permeate fluxes were fitted by the constant pressure fi1tration models in order to investigate fouling steps. In 0.1 wt% mixed solution of equal amount of kaolin and starch, the permeation flux was about 30% lower than the average of each particle flux. However, the permeation flux for kaolin/PMMA mixed solution was about 10% higher than the average of each particle flux. In the cases of bentonite and PMMA or starch mired solution, the improvement effect on permeation flux was weaken than that of kaolin mixed solution. Also, the membrane fouling resistance for mixed particle solution of equal amount of kaolin and starch was minimum at 0.05 wt% particle concentration.

  • PDF

Activating Temperature of Kaolin As a Cement Admixture

  • Park, Hee-Yong;Hwang, Hey-Zoo;Kim, Moo-Han;Kim, Moon-Han
    • KCI Concrete Journal
    • /
    • v.13 no.1
    • /
    • pp.3-9
    • /
    • 2001
  • This research concerns the effect of kaolin as material of cement admixture. which has the advantage of low price and high adaptability. Kaolin, a kind of soil, is well known as a raw material of pottery. which is widely scat-tered on the earth (especially in Korea). This research shows the method and process for activating kaolin to have the properties of a cement admixture through experiment. In the experiments, kaolin is baked in high temperature and then cooled suddenly to be activated. The temperature zone and time span, on which kaolin is activated are examined. The research looks over the effect of the activated kaolin based on several criteria regarding to chemical and physical characteristic of general admixtures. The results of this research are as follows; kaolin start activation at the temperature above 50$0^{\circ}C$ and make ends of activation at the temperature below 95$0^{\circ}C$ and there was little effect by the change of duration. It is concluded that compressive strength can be increased by putting activated kaolin in the concrete and the activated kaolin is good for water resistance and anti-chemical , and that it is effective for protecting the leakage of hazardous article like Cl- and for protecting damage by an organic salt like acid. The activated kaolin of proper temperature and time is effective in compressive strength, salt resistance and acid resistance. The adaptability of activated kaolin as a cement admixture was shown through this research.

  • PDF

Studies on the Surface Treatment of Kaolin Filler(Part I) -Fundamental Properties of Kaolin Filler and Treatment Effect on Physical Properties of Rubbers- (Kaolin 충전제(充塡劑) 표면처리(表面處理)에 관(關)한 연구(硏究)(제1보(第1報)) -Kaolin의 기초성상(基礎性狀) 및 고무물성(物性)에 대(對)한 처리효과(處理效果)-)

  • Kwon, Dong-Yong;Hong, Sung-Il;Lee, Yong-Moo
    • Elastomers and Composites
    • /
    • v.18 no.3
    • /
    • pp.87-98
    • /
    • 1983
  • Fundamental properties and surface treatment effects of domestic kaolin calcined at higher temperature were studied to develop reinforcing fillers for rubbers. The results obtained are as follows: (i) X-ray diffraction and scanning electron microscopy studies revealed kaolinite as a major constituent of the raw kaolin used in this study. (ii) Physical properties of natural rubber vulcanizates compounded with the calcined kaolin fillers treated with poly(maleic anhydride) and sodium polyphosphate are favorably improved. Particularly, the kaolin filler treated with sodium polyphosphate(designated as PT series) shows excellent physical properties compared with hydrated silica.

  • PDF

Studies on the Properties of High Performance and High Strength Cement Mortar Using Meta Kaolin and Silica Fume (Meta Kaolin 및 Silica Fume을 이용한 고성능 고강도 시멘트 모르타르 특성에 관한 연구)

  • 정민철
    • Journal of the Korean Ceramic Society
    • /
    • v.33 no.5
    • /
    • pp.519-523
    • /
    • 1996
  • Calcium hydroxide produced by cement hydration decreases the durability and the compressive strength of cement mortars. Pozzolanic property of meta kaolin and silica fume allows to avoid this drawback. Calcium hydroxide consumption according to pozzolanic raction is evaluated by Fourier differential thermal analysis. Particulary the properties of high performance and high strength of cement mortar containing above 10% meta kaolin and silica fume were resulted in the pozzolanic activity.

  • PDF

Clay Mineral Composition of the Soils Derived from Residuum and Colluvium (잔적 및 붕적모재 토양의 점토광물 특성구명)

  • Zhang, Yong-Seon;Sonn, Yeon-Kyu;Jung, Sug-Jae;Lee, Gye-Jun;Kim, Myung-Sook;Kim, Sun-Kwan;Lee, Ju-Young;Pyun, In-Hwan
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.39 no.5
    • /
    • pp.245-252
    • /
    • 2006
  • This experiment was conducted to investigate the distribution and compositions of clay mineral and to replenish the soil classification system in Korea. Soil layer samples were collected from 26 residuum and colluvium soil series out of 390 soil series in Korea, and then analyzed for soil physical and chemical characteristics, mineral and chemical compositions of clay in B horizon soils. Major clay minerals of residuum and colluvium were illite and chlorite in soils originated from the sedimentary rock such as limestone, shale, sandstone and conglomerate; quartz and kaolin in soils originated from rhyolite, neogene deposits, porphyry and tuff; and kaolin and quartz in the soils originated from granite, granite gneiss and anorthosite. Clay minerals in Korean soils were divided into 4 groups: mixed mineral group(MIX) mainly contained with illite, kaolin and vemiculite; kaolin group(KA) with kaolin and illite; chlorite group(CH) with chlorite and illite; and smectite group(SM) with kaolin, illite and smectite. The most predominant clay mineral group was kaolin group(KA) with kaolin and illite; an mixed mineral group(MIX) with illite, kaolin and vemiculite. Cation exchange capacity (CEC) of clay was low in the soils mainly composed with MIX and KA groups and silica-alumina molar ratio of clay was high in the soils composed with SM group

7$\AA$ Phase in the Sancheong Kaolin : 7$\AA$-Halloysite or Kaolinite\ulcorner (산청 고령토중의 7$\AA$ 상에 대한 연구 : 7$\AA$-할로이사이트 또는 캐올리나이트\ulcorner)

  • 정기영;김수진
    • Journal of the Mineralogical Society of Korea
    • /
    • v.2 no.1
    • /
    • pp.18-25
    • /
    • 1989
  • The X-ray diffraction and electron microscopy study of the kaolin sample from Sancheong area show that the halloysite occurs as hydrated 10$\AA$ form. It implies that the 7$\AA$ reflection and hk-line splitting in the X-ray diffractogram are ascribed to kaolinite. Kaolinite in Sancheong kaolin is of a disordered type. It tends to be enriched in the colored part of kaolin samples. Quantitative analyses show that kaolin contains 16-57% halloysite and 10-55%kaolinite.

  • PDF

A Study of light Weight Porous Concrete Using Meta-kaolin (경량기포콘크리트에 고령토의 첨가효과에 관한 연구)

  • Ganbileg, Gayabazar;Kong, Kyoung-Rok;Kang, Heon-Chan
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.905-908
    • /
    • 2006
  • In this study examines physical and mechanical properties the use of domestic low grade meta-kaolin in light weight porous concrete. For this purpose light weight porous concrete incorporating low grade meta-kaolin admixture, was tested for tensile strength and acoustic characteristics. Checking tensile strength of cement and low grade meta-kaolin mixture was used to determine the optimum mix proportion of the low grade meta-kaolin admixture. In this paper sound absorbing material has been investigated by using the light weight porous concrete.

  • PDF