Pub Date : 2019-01-01DOI: 10.17576/mjas-2019-2302-06
Vivien Ting, T. Ping, A. Abdullah
The excessive release of lead (Pb) ions into water stream and large production of agricultural wastes cause water and land pollution. Adsorption is useful in eliminating Pb(II) from water environment. The potential use of agricultural waste, pineapple plant stem as adsorbent to reduce the amount of Pb(II) in aqueous solutions was investigated. The material was modified with oxalic acid (OA) to improve the adsorption efficiency of Pb(II). Adsorption isotherms and kinetics were determined for the adsorption of Pb(II) on natural pineapple plant stem (NPPS) and OA modified pineapple plant stem (OAPPS) from aqueous solution in batch studies. The adsorption capacity of Pb(II) on pineapple plant stem depends considerably on the solution pH, in which the amount of Pb(II) adsorbed increased with increasing solution pH, reached its maximal with 14.25 mg/g at pH 5 and 30.47 mg/g at pH 4 for NPPS and OAPPS, respectively. The adsorption performance of the adsorbents was also studied at different initial Pb(II) concentrations (50 – 150 mg/L), it was observed to be less affected at higher initial Pb(II) concentration. The adsorption isotherm was then investigated and the equilibrium data were well fitted with the Langmuir isotherm model with 13.30 and 27.70 mg/g as the calculated maximum capacities for NPPS and OAPPS, respectively. The adsorption of Pb(II) onto NPPS and OAPPS reached equilibrium after 60 minutes at all concentrations studied. The kinetics data were found to follow the pseudo-second order model.
{"title":"REMOVAL OF Pb(II) FROM AQUEOUS SOLUTION BY PINEAPPLE PLANT STEM","authors":"Vivien Ting, T. Ping, A. Abdullah","doi":"10.17576/mjas-2019-2302-06","DOIUrl":"https://doi.org/10.17576/mjas-2019-2302-06","url":null,"abstract":"The excessive release of lead (Pb) ions into water stream and large production of agricultural wastes cause water and land pollution. Adsorption is useful in eliminating Pb(II) from water environment. The potential use of agricultural waste, pineapple plant stem as adsorbent to reduce the amount of Pb(II) in aqueous solutions was investigated. The material was modified with oxalic acid (OA) to improve the adsorption efficiency of Pb(II). Adsorption isotherms and kinetics were determined for the adsorption of Pb(II) on natural pineapple plant stem (NPPS) and OA modified pineapple plant stem (OAPPS) from aqueous solution in batch studies. The adsorption capacity of Pb(II) on pineapple plant stem depends considerably on the solution pH, in which the amount of Pb(II) adsorbed increased with increasing solution pH, reached its maximal with 14.25 mg/g at pH 5 and 30.47 mg/g at pH 4 for NPPS and OAPPS, respectively. The adsorption performance of the adsorbents was also studied at different initial Pb(II) concentrations (50 – 150 mg/L), it was observed to be less affected at higher initial Pb(II) concentration. The adsorption isotherm was then investigated and the equilibrium data were well fitted with the Langmuir isotherm model with 13.30 and 27.70 mg/g as the calculated maximum capacities for NPPS and OAPPS, respectively. The adsorption of Pb(II) onto NPPS and OAPPS reached equilibrium after 60 minutes at all concentrations studied. The kinetics data were found to follow the pseudo-second order model.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67647483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-01DOI: 10.17576/mjas-2019-2301-04
M. Miskam, A. Rahman, Fiona How Ni Foong, Y. Chua, Ping Chen, Zhitao Xiong, Hui-yue Wu
The School of Chemical Sciences was established in 1969 and is divided into Organic, Inorganic, Physical, Analytical and Industrial Chemistry sections. The school offers two undergraduate programmes namely Bachelor of Science in Pure Chemistry and Bachelor of Applied Science in Analytical and Industrial Chemistry as well as Master in Chemical Instrumentation, Master and PhD by research. At the Physical Chemistry section, a total of 9 staff are involved in teaching of academic courses at the undergraduate and postgraduate levels. They are also actively conducting research in molecular modelling, green chemistry, environmental science, surface science and materials science such as zeolites, nanomaterials and
{"title":"MITIGATION OF TOXIC Alexandrium tamiyavanichii USING CHITOSAN-SILICA COMPOSITE","authors":"M. Miskam, A. Rahman, Fiona How Ni Foong, Y. Chua, Ping Chen, Zhitao Xiong, Hui-yue Wu","doi":"10.17576/mjas-2019-2301-04","DOIUrl":"https://doi.org/10.17576/mjas-2019-2301-04","url":null,"abstract":"The School of Chemical Sciences was established in 1969 and is divided into Organic, Inorganic, Physical, Analytical and Industrial Chemistry sections. The school offers two undergraduate programmes namely Bachelor of Science in Pure Chemistry and Bachelor of Applied Science in Analytical and Industrial Chemistry as well as Master in Chemical Instrumentation, Master and PhD by research. At the Physical Chemistry section, a total of 9 staff are involved in teaching of academic courses at the undergraduate and postgraduate levels. They are also actively conducting research in molecular modelling, green chemistry, environmental science, surface science and materials science such as zeolites, nanomaterials and","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67646788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-01DOI: 10.17576/mjas-2019-2301-06
Dorairaaj Sivasubramaniam, N. Amin, K. Ahmad, Nur Aainaa Syahirah Ramli
Ethyl levulinate is widely used as a fuel additive, flavor or fragrance and as a component of fuel blending. This study focused on the production of ethyl levulinate from levulinic acid via esterification reaction in the presence of HPW/ZrO2.The catalyst was prepared using the wet impregnation method, characterized by using FTIR, BET and NH3-TPD and screened based on 20%, 40% and 60% HPW/ZrO2. The 40% HPW/ZrO2 catalyst exhibited the highest catalytic performance during the parameter screening stage which included catalyst loading (0.25‒1.25g) and volume ratio of levulinic acid to ethanol (1:4 – 1:8). The highest ethyl levulinate yield of 99% corresponded to a catalyst loading of 0.5 g and volume ratio of levulinic acid to ethanol of 1:5 with reaction conditions at 150 °C for 3 hours. The esterification reaction of levulinic acid revealed that the catalytic performance was influenced by the acid sites and surface area of the catalyst. In addition, volume ratio was also a major factor in enhancing the ethyl levulinate yield.
{"title":"PRODUCTION OF ETHYL LEVULINATE VIA ESTERIFICATION REACTION OF LEVULINIC ACID IN THE PRESENCE OF ZrO2 BASED CATALYST","authors":"Dorairaaj Sivasubramaniam, N. Amin, K. Ahmad, Nur Aainaa Syahirah Ramli","doi":"10.17576/mjas-2019-2301-06","DOIUrl":"https://doi.org/10.17576/mjas-2019-2301-06","url":null,"abstract":"Ethyl levulinate is widely used as a fuel additive, flavor or fragrance and as a component of fuel blending. This study focused on the production of ethyl levulinate from levulinic acid via esterification reaction in the presence of HPW/ZrO2.The catalyst was prepared using the wet impregnation method, characterized by using FTIR, BET and NH3-TPD and screened based on 20%, 40% and 60% HPW/ZrO2. The 40% HPW/ZrO2 catalyst exhibited the highest catalytic performance during the parameter screening stage which included catalyst loading (0.25‒1.25g) and volume ratio of levulinic acid to ethanol (1:4 – 1:8). The highest ethyl levulinate yield of 99% corresponded to a catalyst loading of 0.5 g and volume ratio of levulinic acid to ethanol of 1:5 with reaction conditions at 150 °C for 3 hours. The esterification reaction of levulinic acid revealed that the catalytic performance was influenced by the acid sites and surface area of the catalyst. In addition, volume ratio was also a major factor in enhancing the ethyl levulinate yield.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67646907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-01DOI: 10.17576/mjas-2019-2303-02
N. Ahmad, K. Jumbri, A. Ramli, N. Ghani, H. Ahmad
Salicylate-based protic ionic liquids (PILs) were synthesised, characterised and assessed in this study for potential antioxidant in drug design. The synthesised PILs were known as 3-dimethylamino-1-propanol salicylate (3DMAPS) and 3-diethylamino-1propanol salicylate (3DEAPS). Proton nuclear magnetic resonance (HNMR), Fourier transformation infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterise the synthesised PILs. Furthermore, the antioxidant activity of the synthesised PILs was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Both 3DMAPS and 3DEAPS showed a good antioxidant activity compared to parent acid (salicylic acid) as these two compounds could scavenge 20% of DPPH free radical at a concentration of 66.76 ± 0.09 μM and 27.27 ± 0.10 μM, respectively.
{"title":"SALICYLATE-BASED PROTIC IONIC LIQUIDS AS A POTENTIAL ANTIOXIDANT","authors":"N. Ahmad, K. Jumbri, A. Ramli, N. Ghani, H. Ahmad","doi":"10.17576/mjas-2019-2303-02","DOIUrl":"https://doi.org/10.17576/mjas-2019-2303-02","url":null,"abstract":"Salicylate-based protic ionic liquids (PILs) were synthesised, characterised and assessed in this study for potential antioxidant in drug design. The synthesised PILs were known as 3-dimethylamino-1-propanol salicylate (3DMAPS) and 3-diethylamino-1propanol salicylate (3DEAPS). Proton nuclear magnetic resonance (HNMR), Fourier transformation infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterise the synthesised PILs. Furthermore, the antioxidant activity of the synthesised PILs was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Both 3DMAPS and 3DEAPS showed a good antioxidant activity compared to parent acid (salicylic acid) as these two compounds could scavenge 20% of DPPH free radical at a concentration of 66.76 ± 0.09 μM and 27.27 ± 0.10 μM, respectively.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67647104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-12
Malaysian Journal, Kesan Zeolit, pada Sifat Mekanikal, dan Morfologi, Membran Nrenr, K. Phatcharasit
The main focus of this research is on the organic-inorganic membranes. In this study, the effects of zeolite on natural rubber (NR)/epoxidized natural rubber (ENR) membranes properties were investigated. NR/ENR blends were combined with zeolite in various contents at 0-50 phr by the two-roll mill. The rubber compounds were produced by compression molding at 150 oC to form membranes with thickness of not more than 0.4 mm. NR/ENR blends with zeolite were characterized according to cure characteristics, mechanical properties, swelling properties and scanning electron microscope (SEM). It was found that the mechanical properties of the blends increased with the addition of zeolite for 10 phr while the cure time (tc90) increased with increasing zeolite content. Membranes swelling increased with increasing amount of zeolite (zeolite at 30 phr produced the best results). Meanwhile, the micrograph showed a surface filled with pores-like small holes with the addition of zeolite in the NR/ENR membranes.
{"title":"THE EFFECTS OF ZEOLITE ON MECHANICAL AND MORPHOLOGICAL PROPERTIES OF NR/ENR MEMBRANES","authors":"Malaysian Journal, Kesan Zeolit, pada Sifat Mekanikal, dan Morfologi, Membran Nrenr, K. Phatcharasit","doi":"10.17576/mjas-2018-2205-12","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-12","url":null,"abstract":"The main focus of this research is on the organic-inorganic membranes. In this study, the effects of zeolite on natural rubber (NR)/epoxidized natural rubber (ENR) membranes properties were investigated. NR/ENR blends were combined with zeolite in various contents at 0-50 phr by the two-roll mill. The rubber compounds were produced by compression molding at 150 oC to form membranes with thickness of not more than 0.4 mm. NR/ENR blends with zeolite were characterized according to cure characteristics, mechanical properties, swelling properties and scanning electron microscope (SEM). It was found that the mechanical properties of the blends increased with the addition of zeolite for 10 phr while the cure time (tc90) increased with increasing zeolite content. Membranes swelling increased with increasing amount of zeolite (zeolite at 30 phr produced the best results). Meanwhile, the micrograph showed a surface filled with pores-like small holes with the addition of zeolite in the NR/ENR membranes.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41987929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-11
Zetty Azalea Sutirman, M. M. Sanagi, K. J. A. Karim, A. A. Naim, W. Ibrahim
Wastewater containing heavy metal ions is one of the most serious environmental concerns. Exposure to elevated levels of heavy metals can adversely affect water resources, endangering the ecosystems and human health. Among the various treatment technologies, adsorption using biopolymer seems a promising alternative method. Chitosan is a natural polymer produced from chitin with excellent properties such as biocompatibility, biodegradability and non-toxicity. Moreover, chitosan is known as an effective sorbent due to the presence of amino and hydroxyl groups in its molecules which can serve as attachment sites towards metal ions. Recently, chitosan derivatives as metal ion sorbents have gained considerable attention. These derivatives are prepared by either physical or chemical modifications or both in order to improve chitosan properties in adsorption. This paper discusses recent developments in the modifications of chitosan and the application of the derived materials in the removal of metal ions from aqueous solutions. The mechanisms of adsorption, metal sorption capacities, effect of pH, isotherm and kinetic models are also described.
{"title":"CHITOSAN-BASED ADSORBENTS FOR THE REMOVAL OF METAL IONS FROM AQUEOUS SOLUTIONS","authors":"Zetty Azalea Sutirman, M. M. Sanagi, K. J. A. Karim, A. A. Naim, W. Ibrahim","doi":"10.17576/mjas-2018-2205-11","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-11","url":null,"abstract":"Wastewater containing heavy metal ions is one of the most serious environmental concerns. Exposure to elevated levels of heavy metals can adversely affect water resources, endangering the ecosystems and human health. Among the various treatment technologies, adsorption using biopolymer seems a promising alternative method. Chitosan is a natural polymer produced from chitin with excellent properties such as biocompatibility, biodegradability and non-toxicity. Moreover, chitosan is known as an effective sorbent due to the presence of amino and hydroxyl groups in its molecules which can serve as attachment sites towards metal ions. Recently, chitosan derivatives as metal ion sorbents have gained considerable attention. These derivatives are prepared by either physical or chemical modifications or both in order to improve chitosan properties in adsorption. This paper discusses recent developments in the modifications of chitosan and the application of the derived materials in the removal of metal ions from aqueous solutions. The mechanisms of adsorption, metal sorption capacities, effect of pH, isotherm and kinetic models are also described.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45364808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-14
Malaysian Journal, A. Aziz, M. Azizi, C. Yunus, Ni Yian, Fahim Rithwan, H. M. Hadzri, A. N. Mustapha
Sinensetin is a rare valuable flavonoid compound that contains 5 methoxy groups attached on the flavone backbone. This compound is abundantly established in citrus peel and can also be found in medicinal herb, ‘misai kucing’. Scientifically, ‘misai kucing’ is known as Orthosiphon stamineus; mostly used to treat kidney stones by old folks. Orthosiphon stamineus was listed in National Key Economic Area (NKEA) as contributor towards the Malaysian Economic Growth. Thus, this study was conducted with objectives to determine suitable modifier for supercritical carbon dioxide (SC-CO2) extraction and to optimize the SC-CO2 extraction condition (pressure, temperature and average particle size) on the concentration of sinensetin. Water, methanol and acetone were used on the determination of modifier for SC-CO2 extraction by using water bath extraction at 40 °C in 8 hours. The results showed that acetone gave the highest percentage of sinensetin extract of 0.11%. Therefore, acetone was used as a modifier to enhance the extraction of sinensetin. The concentration of sinensetin was increased and the highest percentage of sinensetin obtained was 6.99%. Response surface methodology (RSM) through Box-Behnken design via Design Expert Software was applied to optimize the SC-CO2 conditions. The first-order polynomial was used to express the percentage of sinensetin with R value of 0.542. The optimum SC-CO2 operating condition was 30 MPa, 40 °C and 308.24 μm with sinensetin percentage of 4.35%. Hence, SC-CO2 with small amount of modifier was the best method to extract sinensetin as compared to water bath extraction method.
{"title":"ENHANCEMENT AND OPTIMIZATION OF SINENSETIN EXTRACT FROM Orthosiphon stamineus USING SUPERCRTITICAL CARBON DIOXIDE EXTRACTION","authors":"Malaysian Journal, A. Aziz, M. Azizi, C. Yunus, Ni Yian, Fahim Rithwan, H. M. Hadzri, A. N. Mustapha","doi":"10.17576/mjas-2018-2205-14","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-14","url":null,"abstract":"Sinensetin is a rare valuable flavonoid compound that contains 5 methoxy groups attached on the flavone backbone. This compound is abundantly established in citrus peel and can also be found in medicinal herb, ‘misai kucing’. Scientifically, ‘misai kucing’ is known as Orthosiphon stamineus; mostly used to treat kidney stones by old folks. Orthosiphon stamineus was listed in National Key Economic Area (NKEA) as contributor towards the Malaysian Economic Growth. Thus, this study was conducted with objectives to determine suitable modifier for supercritical carbon dioxide (SC-CO2) extraction and to optimize the SC-CO2 extraction condition (pressure, temperature and average particle size) on the concentration of sinensetin. Water, methanol and acetone were used on the determination of modifier for SC-CO2 extraction by using water bath extraction at 40 °C in 8 hours. The results showed that acetone gave the highest percentage of sinensetin extract of 0.11%. Therefore, acetone was used as a modifier to enhance the extraction of sinensetin. The concentration of sinensetin was increased and the highest percentage of sinensetin obtained was 6.99%. Response surface methodology (RSM) through Box-Behnken design via Design Expert Software was applied to optimize the SC-CO2 conditions. The first-order polynomial was used to express the percentage of sinensetin with R value of 0.542. The optimum SC-CO2 operating condition was 30 MPa, 40 °C and 308.24 μm with sinensetin percentage of 4.35%. Hence, SC-CO2 with small amount of modifier was the best method to extract sinensetin as compared to water bath extraction method.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":"2019 31-32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41262755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-04
Sintesis dan Sifat Fizikokimia, Nanopartikel Magnetit Fe3O, Sebagai Penyokong, Pepejal Bagi, Mangkin Homogen, Wan Fatihah Khairunisa, W. Nor, S. K. C. Soh, Azzura Abd Rahman Azmi, M. Yusof
Black and dark magnetite nanoparticles (MNPs) were successfully synthesised through a co-precipitation method as a crucial material to support palladium(II) complexes as they have the potential to become a stable solid support for homogeneous systems. The two-hour synthesis was done by mixing FeCl3.6H2O and FeCl2.4H2O in an alkaline medium. To improve the properties of iron oxide nanoparticles, the process was done under inert conditions. The physicochemical properties of this support was then characterised using various spectroscopic techniques such as Fourier Transform Infrared (FTIR) spectroscopy that shows the X-ray diffraction analysis (XRD), Thermogravimetric analysis (TGA), Field Emission Scanning Electron Microscope (FESEM), and Vibrating Sample Magnetometer (VSM). The pore size distribution and the specific BET surface area were measured by N2 adsorption-desorption isotherms. The FTIR absorption spectroscopy was used to confirm the formation of Fe-O bond. The most intense peak correspond to the (311) crystallographic orientation of the spinel cubic phase of MNPs shown by XRD pattern result. The particle size of magnetite was successfully controlled in the range of 20-40 nm. All of the MNPs showed the superparamagnetic behaviour with high saturation magnetization.
{"title":"SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF MAGNETITE NANOPARTICLES (Fe3O4) AS POTENTIAL SOLID SUPPORT FOR HOMOGENEOUS CATALYSTS","authors":"Sintesis dan Sifat Fizikokimia, Nanopartikel Magnetit Fe3O, Sebagai Penyokong, Pepejal Bagi, Mangkin Homogen, Wan Fatihah Khairunisa, W. Nor, S. K. C. Soh, Azzura Abd Rahman Azmi, M. Yusof","doi":"10.17576/mjas-2018-2205-04","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-04","url":null,"abstract":"Black and dark magnetite nanoparticles (MNPs) were successfully synthesised through a co-precipitation method as a crucial material to support palladium(II) complexes as they have the potential to become a stable solid support for homogeneous systems. The two-hour synthesis was done by mixing FeCl3.6H2O and FeCl2.4H2O in an alkaline medium. To improve the properties of iron oxide nanoparticles, the process was done under inert conditions. The physicochemical properties of this support was then characterised using various spectroscopic techniques such as Fourier Transform Infrared (FTIR) spectroscopy that shows the X-ray diffraction analysis (XRD), Thermogravimetric analysis (TGA), Field Emission Scanning Electron Microscope (FESEM), and Vibrating Sample Magnetometer (VSM). The pore size distribution and the specific BET surface area were measured by N2 adsorption-desorption isotherms. The FTIR absorption spectroscopy was used to confirm the formation of Fe-O bond. The most intense peak correspond to the (311) crystallographic orientation of the spinel cubic phase of MNPs shown by XRD pattern result. The particle size of magnetite was successfully controlled in the range of 20-40 nm. All of the MNPs showed the superparamagnetic behaviour with high saturation magnetization.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46692936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-18
Malaysian Journal, Terisi Sepiolit, N. M. Zaini
The effects of different sepiolite contents on the thermal stability, flammability, and morphological properties of sepiolite-filled ethylene-propylene-diene monomer composites were studied. These sepiolite-filled composites, containing 0-70 parts per hundred rubber (phr) of sepiolite fillers, were prepared through the conventional processing method of using a two-roll mill. The results demonstrated a significant increase in the thermal stability of the composites when sepiolite loading was increased compared to unfilled composites. The results also showed a decrease in the linear rate of burning of the composites with increasing sepiolite loading. The morphological study confirmed the presence of unburned sepiolite, which increased the flammability resistance of the composites.
{"title":"THERMAL, FLAMMABILITY, AND MORPHOLOGICAL PROPERTIES OF SEPIOLITE-FILLED ETHYLENE PROPYLENE DIENE MONOMER COMPOSITES","authors":"Malaysian Journal, Terisi Sepiolit, N. M. Zaini","doi":"10.17576/mjas-2018-2205-18","DOIUrl":"https://doi.org/10.17576/mjas-2018-2205-18","url":null,"abstract":"The effects of different sepiolite contents on the thermal stability, flammability, and morphological properties of sepiolite-filled ethylene-propylene-diene monomer composites were studied. These sepiolite-filled composites, containing 0-70 parts per hundred rubber (phr) of sepiolite fillers, were prepared through the conventional processing method of using a two-roll mill. The results demonstrated a significant increase in the thermal stability of the composites when sepiolite loading was increased compared to unfilled composites. The results also showed a decrease in the linear rate of burning of the composites with increasing sepiolite loading. The morphological study confirmed the presence of unburned sepiolite, which increased the flammability resistance of the composites.","PeriodicalId":39007,"journal":{"name":"Malaysian Journal of Analytical Sciences","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49192791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-25DOI: 10.17576/mjas-2018-2205-01
Malaysian Journal, P. W. Chia, P. Chee, Siti Nur Aqlili, Riana Mohd Asseri, Su-Yin Kan
The biaryl and its derivatives are important organic compounds that possess various interesting applications, such as in the field of medicine, organic-light emitting materials, agrochemicals and other functional properties. Traditionally, radical arylation of arylhydrazines and anilines requires the use of metals, excess of base, flammable solvent and so on. Thus, a greener catalytic system for the synthesis of 2-aminobiaryls is highly sought after. In this work, a recyclable catalytic media has been developed for the synthesis of 2-aminobiaryl derivatives via a direct arylation of anilines with arylhydrazines in the presence of water extract of the burned-ash of onion peel waste (ash-water extract). This method provides numerous advantages, such as external baseand metal-free, recyclable catalytic system, inexpensive and the products were achieved in moderate to good yield. This sustainable synthesis is scientifically important, as it is capable of minimizing the use of toxic reagents and at the same time offers an alternative method to manage the abundant bio-waste.
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