• Korean Journal of Materials Research
• /
• v.28 no.1
• /
• pp.62-67
• /
• 2018

Active clay, bentonite and zeolite were used as porous materials for humidity controlling ceramic boards. The specific area and the pore volume of active clay were higher than bentonite and zeolite. The flexible strength of the gypsum board decreased with an increasing amount of porous material, and the flexible strength was lowest when active clay with a higher specific surface area than others porous materials was added. The specific surface area and total pore volume of ceramic boards containing porous material were highest at $102.25m^2/g$, $0.142cm^3/g$, respectively, when the active clay was added. In addition, as the amount of added porous materials increased, the specific surface area and total pore volume of the ceramic board increased, but the average pore diameter decreased. The addition of s porous materials with a high specific area and a large pore volume improved the moisture absorptive and desorptive performance of the ceramic board. Therefore, in this experiment, the moisture absorptive and desorptive properties were the best when active clay was added. Furthermore, as the amount of added porous materials increased, the moisture absorptive and desorptive properties improved. When 70 mass% of active clay was added to ${\alpha}$-type gypsum, the hygroscopicity was the highest, about $300g/m^2$, in this experiment.

• Journal of the Korean Chemical Society
• /
• v.66 no.2
• /
• pp.78-85
• /
• 2022

Natural white clay was treated with 6 M of H₂SO₄ and heated at 80℃ for 6 h under mechanical stirring and the resulting acid active clay was used as an adsorbent for the removal of Cs⁺ in water. The physicochemical changes of natural white clay and acid active clay were observed by X-ray Fluorescence Spectrometry (XRF), BET Surface Area Analyser and Energy Dispersive X-line Spectrometer (EDX). While activating natural white clay with acid, the part of Al₂O₃, CaO, MgO, SO₃ and Fe₂O₃ was dissolved firstly from the crystal lattice, which bring about the increase in the specific surface area and the pore volume as well as active sites. The specific surface area and the pore volume of acid active clay were roughly twice as high compared with natural white clay. The adsorption of Cs⁺ on acid active clay was increased rapidly within 1 min and reached equilibrium at 60 min. At 25 mg L^- of Cs⁺ concentration, 96.88% of adsorption capacity was accomplished by acid active clay. The adsorption data of Cs⁺ were fitted to the adsorption isotherm and kinetic models. It was found that Langmuir isotherm was described well to the adsorption behavior of Cs⁺ on acid active clay rather than Freundlich isotherm. For adsorption Cs⁺ on acid active clay, the Langmuir isotherm coefficients, Q, was found to be 10.52 mg g^-1. In acid active clay/water system, the pseudo-second-order kinetic model was more suitable for adsorption of Cs⁺ than the pseudo-first-order kinetic model owing to the higher correlation coefficient R² and the more proximity value of the experimental value q_e,exp and the calculated value q_e,cal. The overall results of study showed that acid active clay could be used as an efficient adsorbent for the removal of Cs⁺ from water.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.4
• /
• pp.57-62
• /
• 2018

This study was designed to analyze the chemical composition and antioxidant activity of various vegetable oils (pumpkin seed oil, camellia seed oil, red pepper seed oil and peanut oil) using adsorbents (active carbon, acid clay, kaolin). Their chemical composition was analyzed by GCMS. Their antioxidant activity was evaluated by measuring their DPPH and ABTS radical scavenging activity. After the treatment with the adsorbents, the contents of most of the fatty acids and active ingredients contained in the four kinds of vegetable oils were reduced. After the treatment with the three adsorbents, the linoleic acid and erythrodiol contents of the pumpkin seed oil were reduced. In the case of the camellia seed oil, the fatty acids content was decreased, but there was no loss of vitamin E after the acid clay treatment. The content of the compound capsaicin, which forms part of the spicy component of red pepper seed oil, was reduced by 53.33% after the acid clay treatment. The peanut oil showed the lowest loss of sitosterol compound in the group treated with active carbon. The antioxidant activity was observed to be in the order of pumpkin seed oil (kaolin>acid clay>active carbon), camellia seed oil (acid clay>kaolin>active carbon), red pepper seed oil (kaolin>acid clay>active carbon) and peanut oil (active carbon>acid clay>kaolin).

• Journal of the Korean Ceramic Society
• /
• v.55 no.1
• /
• pp.74-79
• /
• 2018

Active clay, bentonite and zeolite were used as porous materials for humidity controlling ceramic boards. The specific area and the pore volume of active clay were higher than those of bentonite and zeolite. It was effective to add white cement as well as a retarding agent to control the setting time of the ceramic paint. As the amount of added porous materials increases, the specific surface area and total pore volume of ceramic paint increase, but the average pore diameter decreases. The addition of porous materials having a high specific area and a large pore volume improves the moisture absorptive and desorptive performance of the ceramic paint. Therefore, in this experiment, the moisture absorptive and desorptive properties were best when active clay was added. Also, as the added amount of porous materials increases, the moisture absorptive and desorptive properties improve. In this experiment, when 70 mass% of active clay was added to ceramic paint, the hygroscopicity was highest at about $80g/m^2$.

• Journal of Environmental Science International
• /
• v.30 no.10
• /
• pp.803-809
• /
• 2021

This study aimed to investigate the effects of soil amendment (heat-expanded clay and active carbon) and planting of Dendranthema zawadskii var. latilobum on the remediation of salt-affected soil and the plant growth under high calcium chloride (CaCl₂) concentration. The experimental group comprised treatments including Non treatment (Cont.), heat-expanded clay (H), active carbon (AC), planting (P), heat-expanded clay+planting (H+P), active carbon+planting (AC+P). A 200 mL solution of CaCl₂ at a concentration of 10 g·L^-1 was applied as irrigation once every 2 weeks. Compared to the Cont., the incorporation of the 'heat-expanded clay' amendment decreased electrical conductivity of the soil leachate and cation exchange capacity, whereas the growth of Dendranthema zawadskii var. latilobum was relatively increased. These results suggest that the combination of 'heat-expanded clay' amendment and planting will mitigate negative effect of de-icing salts and improve plant growth in salt-contaminated roadside soils.

• Economic and Environmental Geology
• /
• v.48 no.3
• /
• pp.221-229
• /
• 2015

Clay minerals have been used in pharmaceutical industries as active ingredients and excipients without pharmacological activity such as diluents, emulsifying agents, viscosity-increasing agents, and lubricants. For example, bentonite, kaolin, magnesium aluminum silicate, and talc are generally and extensively used pharmaceutical ingredients, which are restrictedly regulated by Pharmacopoeias. We discuss the physicochemical and biopharmaceutical properties of clay minerals. In addition, we introduce the cases of pharmaceutical applications of clay minerals. From this review, pharmaceutical applications of clay minerals can be one of strategies for the development of high value-added products from clay minerals.

• KSBB Journal
• /
• v.15 no.4
• /
• pp.342-345
• /
• 2000

A novel pre-purification method was developed for producing peroxidase to guarantee high purity and yield from plant cell cultures in large-scale process. This method was a simple and efficient procedure for the isolation and pre-purification of peroxidase from the biomass consisting of active clay treatment followed by cationic exchange chromatography. The use of active clay in the pre-purification process allows for rapid and efficient separation of peroxidase from interfering compounds and dramatically increases yield and purity of crude peroxidase for purification steps compared to alternative processes. This pre-purification process serves to minimize the buffer usage size and complexity of the HPLC operations for peroxidase purification. This process is readily scalable to a pilot plant and eventually to a production environment where mass production of material are expected to be produced.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.6
• /
• pp.770-773
• /
• 1999

To obtain the basic data for the improvement of flayer and color in salt-fermented anchovy (Engraulis japonicus) sauce and for the inhibition of non-soluble precipitates formation during storage, experiments were carried out on the changes of chemical properties by treatment with 1, 3, 5 and $7\%$ (w/v) of active carbon and filter aids such as active clay, $Al_2O_3$ diatomaceous earth, and celite. Deceleration rate were $32\~33\%$ in case of $5\%$ (w/v) active carbon or $5\%$ (w/v) active clay treatments, but deodoration effect was not expected in all treatments. The inhibition rate of non-soluble precipitates formation in me of $5\%$ (w/v) active clay, diatomaceous earth and $Al_2O_3$ treatments. was shown as $82\%,\;73\%$, and $70\%$, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.06a
• /
• pp.189-190
• /
• 2020

The importance of indoor air quality management has recently been highlighted due to environmental problems such as indoor air pollution. Among indoor air pollutants, carbon dioxide occurs in cooking, heating, burning, and causes forgetfulness, dementia and amnesia. Radon, which occurs in building materials, soil and ground, is a type 1 carcinogen that causes lung cancer in the body through breathing. These substances can be released from the room through ventilation, but there is a limit to reducing the amount of indoor activity due to reduced ventilation conditions due to increased indoor activity time. However, these substances can be removed from the gas by adsorption. The purpose of this study was to identify the properties of granular active and powdered active white soil and mix them to make cement-based active white soil adsorbent matrix for carbon dioxide, fine dust and radon gas adsorption, and to evaluate indoor air improvements according to the mixing scale. The results of the experiment showed that active carbon dioxide adsorption performance increased for carbon dioxide and radon as the exchange rate increased through physical adsorption. In particular, the higher the replacement rate of the granular active bag, the better adsorption performance was shown.

• Structural Engineering and Mechanics
• /
• v.6 no.3
• /
• pp.245-257
• /
• 1998

This paper present an analysis which may be used to obtain a rational design of a system of inclined piles used in preventing downhill creep of unsaturated clay formations. It uses two simple and relatively easy to measure parameters (an estimate of the maximum downhill creep together with a knowledge of the depth of the so called active zone) to calculate the required section size and the optimal spacing (pitch) of the piles for a desired efficiency of the system as a whole. Design charts are provided to facilitate the process.