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Agnieszka Rozycka - One of the best experts on this subject based on the ideXlab platform.
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utilization of waste expanded Perlite as new effective supplementary cementitious material
Journal of Cleaner Production, 2017Co-Authors: łukasz Kotwica, Waldemar Pichor, Ewa Kapeluszna, Agnieszka RozyckaAbstract:Abstract Expanded Perlite is a valuable lightweight material for building materials industry as well as for agriculture, horticulture etc. Unfortunately during both production as well as processing of expanded Perlite, some fine grained waste Perlite is being formed. Due to its extremely low bulk density waste expanded Perlite is difficult to handle, utilize and causes dust formation. Paper presents method of utilization of waste expanded Perlite as a valuable, high performance pozzolanic supplementary cementitious material. Waste expanded Perlite was ground in ball mill in order to destroy cellular microstructure of waste expanded Perlite. It resulted in significant increase in specific surface area of material. Results of strength tests showed, that addition of ground waste expanded Perlite may result in strength gain up to 50% (for 35% addition in respect to cement mass). Due to its high activity ground waste expanded Perlite can be used as both cement substitute as well as cement additive depending on desired properties of final material. Investigations showed, that ground waste expanded Perlite is material of pozzolanic activity. Except strength test, pozzolanic activity was investigated by solubility test according to ASTM C379-65T. Direct measurements of calcium hydroxide content in hydrating alite pastes confirmed that ground expanded Perlite reacts with calcium hydroxide what results in reduction of calcium hydroxide content in alite paste. Pozzolanic activity of ground waste expanded Perlite was compared with commonly used commercial pozzolanas. Obtained results allow to classify ground waste expanded Perlite as material of pozzolanic properties. It can be valuable supplementary cementitous material mainly for special applications due to its high pozzolanic activity and very bright, almost white colour. In addition to that, ground waste expanded Perlite used as cement replacement allows to decrease carbon dioxide emission, since Portland cement manufacturing is connected with emission of considerable amount of carbon dioxide.
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effect of Perlite waste addition on the properties of autoclaved aerated concrete
Construction and Building Materials, 2016Co-Authors: Agnieszka Rozycka, Waldemar PichorAbstract:Abstract In presented paper, the influence of expanded Perlite waste on the properties of autoclaved aerated concrete (AAC) was investigated. Expanded Perlite waste was used as a quartz sand replacement in conventional AAC mixtures at 5%, 10%, 20%, 30% and 40% by weight. Results show that use of expanded Perlite waste in AAC caused a unit weight decrease in the produced AAC, it is connected with the changes in the properties of AAC. The thermal conductivity coefficient and compressive strength of specimens decreased as the amount of expanded Perlite waste increased in AAC. The introduction of Perlite waste up to 10% by weight reduced the thermal conductivity about 15% without significant reduction of compressive strength. Further improvement of thermal conductivity may be obtained by the addition of Perlite waste up to 30%, but it caused reduction compressive strength about 20%. The minimum thermal conductivity value was 0.074 W/m·K, observed at 40% expanded Perlite waste replacement. The structural and microstructural investigations showed that expanded Perlite waste has a positive influence on the formation of calcium silicate hydrates (1.1 nm tobermorite) in AAC. From this result, it was concluded that expanded Perlite waste can potentially be used as quartz sand replacement in the production of AAC.
Waldemar Pichor - One of the best experts on this subject based on the ideXlab platform.
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utilization of waste expanded Perlite as new effective supplementary cementitious material
Journal of Cleaner Production, 2017Co-Authors: łukasz Kotwica, Waldemar Pichor, Ewa Kapeluszna, Agnieszka RozyckaAbstract:Abstract Expanded Perlite is a valuable lightweight material for building materials industry as well as for agriculture, horticulture etc. Unfortunately during both production as well as processing of expanded Perlite, some fine grained waste Perlite is being formed. Due to its extremely low bulk density waste expanded Perlite is difficult to handle, utilize and causes dust formation. Paper presents method of utilization of waste expanded Perlite as a valuable, high performance pozzolanic supplementary cementitious material. Waste expanded Perlite was ground in ball mill in order to destroy cellular microstructure of waste expanded Perlite. It resulted in significant increase in specific surface area of material. Results of strength tests showed, that addition of ground waste expanded Perlite may result in strength gain up to 50% (for 35% addition in respect to cement mass). Due to its high activity ground waste expanded Perlite can be used as both cement substitute as well as cement additive depending on desired properties of final material. Investigations showed, that ground waste expanded Perlite is material of pozzolanic activity. Except strength test, pozzolanic activity was investigated by solubility test according to ASTM C379-65T. Direct measurements of calcium hydroxide content in hydrating alite pastes confirmed that ground expanded Perlite reacts with calcium hydroxide what results in reduction of calcium hydroxide content in alite paste. Pozzolanic activity of ground waste expanded Perlite was compared with commonly used commercial pozzolanas. Obtained results allow to classify ground waste expanded Perlite as material of pozzolanic properties. It can be valuable supplementary cementitous material mainly for special applications due to its high pozzolanic activity and very bright, almost white colour. In addition to that, ground waste expanded Perlite used as cement replacement allows to decrease carbon dioxide emission, since Portland cement manufacturing is connected with emission of considerable amount of carbon dioxide.
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effect of Perlite waste addition on the properties of autoclaved aerated concrete
Construction and Building Materials, 2016Co-Authors: Agnieszka Rozycka, Waldemar PichorAbstract:Abstract In presented paper, the influence of expanded Perlite waste on the properties of autoclaved aerated concrete (AAC) was investigated. Expanded Perlite waste was used as a quartz sand replacement in conventional AAC mixtures at 5%, 10%, 20%, 30% and 40% by weight. Results show that use of expanded Perlite waste in AAC caused a unit weight decrease in the produced AAC, it is connected with the changes in the properties of AAC. The thermal conductivity coefficient and compressive strength of specimens decreased as the amount of expanded Perlite waste increased in AAC. The introduction of Perlite waste up to 10% by weight reduced the thermal conductivity about 15% without significant reduction of compressive strength. Further improvement of thermal conductivity may be obtained by the addition of Perlite waste up to 30%, but it caused reduction compressive strength about 20%. The minimum thermal conductivity value was 0.074 W/m·K, observed at 40% expanded Perlite waste replacement. The structural and microstructural investigations showed that expanded Perlite waste has a positive influence on the formation of calcium silicate hydrates (1.1 nm tobermorite) in AAC. From this result, it was concluded that expanded Perlite waste can potentially be used as quartz sand replacement in the production of AAC.
S. Mahjouri - One of the best experts on this subject based on the ideXlab platform.
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Effect of explant source, Perlite nanoparticles and TiO2/Perlite nanocomposites on phytochemical composition of metabolites in callus cultures of Hypericum perforatum
Scientific Reports, 2019Co-Authors: R. Ebadollahi, Saeed Jafarirad, Morteza Kosari-nasab, S. MahjouriAbstract:It appears that the biologically-synthesized nanoparticles (NPs) have potential to perform as effective elicitors for the production of valuable secondary metabolites in plants. Besides, it has been reported that the toxicity of the biologically-synthesized NP is not as much as that of the chemically-synthesized NPs. Therefore, it is necessary to test their advantages aspects. In this study, the physical synthesis of Perlite NPs and biologically-synthesis of TiO2/Perlite nanocomposites (NCs) were conducted. Subsequently, their effects and explant source influence on the growth characteristics and secondary metabolite profiles of Hypericum perforatum callus cultures were evaluated. According to the obtained results, morphology of the synthesized Perlite NPs and TiO2/Perlite NCs were mesoporous and spherical with sizes ranging about 14.51–23.34 and 15.50–24.61 nm, respectively. Addition of Perlite NPs and TiO2/Perlite NCs to the culture medium at the concentration range of 25–200 mg/L showed no adverse impacts on the growth characteristics of H. perforatum calli. According to the GC-MS analysis, the stress caused by Perlite NPs and TiO2/Perlite NCs led to an increase in the variety, amount and number of volatile compounds. The calli obtained from in vitro grown plants produced more volatile compounds relative to the calli obtained from field grown plants under the nanomaterial stress conditions. The production of hypericin and pseudohypericin were also determined in the callus cultures under desired nanomaterials elicitation. Accordingly, our results suggest that Perlite NPs and TiO2/Perlite NCs can possibly be considered as effective elicitors for the production of volatile compounds, hypericin, and pseudohypericin in callus cultures of H. perforatum.
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Effect of explant source, Perlite nanoparticles and TiO 2 /Perlite nanocomposites on phytochemical composition of metabolites in callus cultures of Hypericum perforatum
Scientific Reports, 2019Co-Authors: R. Ebadollahi, Saeed Jafarirad, Morteza Kosari-nasab, S. MahjouriAbstract:It appears that the biologically-synthesized nanoparticles (NPs) have potential to perform as effective elicitors for the production of valuable secondary metabolites in plants. Besides, it has been reported that the toxicity of the biologically-synthesized NP is not as much as that of the chemically-synthesized NPs. Therefore, it is necessary to test their advantages aspects. In this study, the physical synthesis of Perlite NPs and biologically-synthesis of TiO2/Perlite nanocomposites (NCs) were conducted. Subsequently, their effects and explant source influence on the growth characteristics and secondary metabolite profiles of Hypericum perforatum callus cultures were evaluated. According to the obtained results, morphology of the synthesized Perlite NPs and TiO2/Perlite NCs were mesoporous and spherical with sizes ranging about 14.51-23.34 and 15.50-24.61 nm, respectively. Addition of Perlite NPs and TiO2/Perlite NCs to the culture medium at the concentration range of 25-200 mg/L showed no adverse impacts on the growth characteristics of H. perforatum calli. According to the GC-MS analysis, the stress caused by Perlite NPs and TiO2/Perlite NCs led to an increase in the variety, amount and number of volatile compounds. The calli obtained from in vitro grown plants produced more volatile compounds relative to the calli obtained from field grown plants under the nanomaterial stress conditions. The production of hypericin and pseudohypericin were also determined in the callus cultures under desired nanomaterials elicitation. Accordingly, our results suggest that Perlite NPs and TiO2/Perlite NCs can possibly be considered as effective elicitors for the production of volatile compounds, hypericin, and pseudohypericin in callus cultures of H. perforatum.
Atsushi Nakahira - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of zeolite-surface-modified Perlite and their heavy metal adsorption capability
Materials Today: Proceedings, 2019Co-Authors: Makoto Kasai, Yosei Kobayashi, Masakazu Togo, Atsushi NakahiraAbstract:Abstract Perlite is volcanic glass of amorphous aluminum silicate, mainly composed SiO2 and Al2O3. Perlite is used for lightweight aggregate and insulation. In addition, it has also been used as a filter aid by grinding the expanded Perlite. However, it has not been used as environmental cleanup materials, because the ion exchange capacity of the Perlite is very low. In this study, we tried to synthesize the hybrid filter aid with chemical adsorption capacity by synthesizing the zeolite on the surface of the Perlite. As a result, it was confirmed that zeolite surface-modified Perlite with LTA zeolite formed on the Perlite surface was synthesized by hydrothermal synthesis method and it had adsorption ability of heavy metal such as zinc
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Synthesis and Evaluation of Zeolite Surface-Modified Perlite
MATEC Web of Conferences, 2017Co-Authors: Makoto Kasai, Yosei Kobayashi, Masakazu Togo, Atsushi NakahiraAbstract:Perlite is volcanic glass mainly composed of amorphous aluminum silicate, mainly composed SiO 2 and Al 2 O 3 with less impurities such as heavy metals. Amorphous (glassy) Perlite is used in lightweight aggregate and insulation. In addition, it has also been used as a filter aid by grinding the expanded Perlite. However, it has not been used as environmental cleanup materials, because the ion exchange capacity of the Perlite is very low. In this study, we tried to synthesize the hybrid filter aid with chemical adsorption capacity by synthesizing the zeolite on the surface of the Perlite. As a result, by using the hydrothermal synthesis method, zeolite surface modified Perlite was synthesized in which the LTA type zeolites were generated on the surface of the Perlite.
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Synthesis and Evaluation of FAU Type Zeolite from Waste Perlite
DEStech Transactions on Engineering and Technology Research, 2017Co-Authors: Makoto Kasai, Yosei Kobayashi, Masakazu Togo, Mitsunori Kondo, Masataka Kamitani, Atsushi NakahiraAbstract:Perlite is an amorphous aluminum silicate, mainly composed of SiO2 and Al2O3. In this study, we tried to synthesize FAU type zeolite from a Perlite as a starting material. It was found that the mechano-chemical treatment (milling process) for Perlite as a raw material resulted in the activation of its surface. As a result, nano-sized FAU-type zeolites with higher Si/Al ratio were preferentially synthesized for Perlite with surface activated by mechano-chemical treatments.
R. Karakas - One of the best experts on this subject based on the ideXlab platform.
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Modification of Perlite for Use as a Thin-Layer Chromatographic Adsorbent
Journal of Chromatographic Science, 1998Co-Authors: R. Karakas, U. YukselAbstract:The SiO 2 content (70-75%) of mineral Perlite is converted to soluble silicates with Na 2 CO 3 . The acidification of soluble silicates in Perlite forms hydrogels which become xerogels upon drying. The parameters (particle size, specific surface area, pore size and volume, and surface hydroxyl group density) are investigated for Perlite modified by Na 2 CO 3 before use as a thin-layer chromatography adsorbent. The modified Perlite is mixed with caSO 4 (a binder) and Na 4 SiO 4 in order to adjust the pH of its 10% suspension in water before its application to the glass surface. The modified Perlite (having CaSO 4 and Na 4 SiO 4 ) is called Perlite IIG7. Layers prepared with Perlite IIG7 are successfully used for the separation of the dye component in commercially available inks, amino acids, carboxylic acids, mono- and disaccarides, and halide ions.
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PREPARATION OF A CHROMATOGRAPHIC SOLID SUPPORT ON THE BASIS OF Perlite, AND SEPARATION OF URANIUM ON A TRIBUTYL-PHOSPHATE-LOADED Perlite COLUMN
Separation Science and Technology, 1998Co-Authors: H. Akçay, S. Kilinç, R. KarakasAbstract:ABSTRACT The SiO2 content of the mineral Perlite, which is the 70–75% range, was converted to soluble silicates with NaOH. The acidification of soluble silicates in the Perlite formed hydrogels which turned into xerogels upon drying. Several parameters, particle size, specific surface area, pore size and volume, and surface hydroxyl group density were investigated for Perlite standardized by NaOH. The standardized Perlite was silanized and loaded with 20% (w/w) tributyl phosphate before use as a reversed- phase column chromatograghy solid support for the investigation of the chromatographic behavior of UO2 2+ and Fe3+.
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Preparation of a chromatographic solid support on the basis of Perlite and separation of uranium on a TBP-loaded Perlite column
Journal of Radioanalytical and Nuclear Chemistry, 1998Co-Authors: H. Akçay, S. Kilinç, R. KarakasAbstract:The possibilities of preparing a packing for reversed phase column chromatography from Menderes' Perlite were studied. Its physical and chemical characteristics were compared with other solid supports prepared from rocks, such as Perlite and volcanic slags. A series of chemical treatments were applied to improve the mechanical and chemical properties of Perlite. The experimental work covers the strong acid treatment, the strong base treatment and the silanization with DMCS. The raw Perlite containing 70–73% SiO2 was treated with NaOH to make soluble silicates and to increase it. Thus the surface and mechanical characters of the modified Perlite were determined. The mean surface OH group density and the specific surface area were 3.2 μmol/m2 and 9.2 m2/g, respectively. The modified Perlite was silanized and hydrophized to load organic complexing agents. The TBP was fixed successfully on Perlite up to 20% w/w. The packing prepared was used to study the chromatographic behavior of UO22+ Fe3+.