Miranda Amiroh Sulaiman, S. Zullaikah, Hoo Peng Yong, A. Quitain
Monoglycerides (MAG) and Diglycerides (DAG) have wide applications in the food, pharmaceutical and cosmetic industries. Despite the economic competitiveness of producing this type of emulsifier from vegetable oils, the increasing demand for products with high nutritional value makes certain types of healthy oils such as rice bran oil (RBO) a potential raw material for high quality fats to serve this growing market. However, the high free fatty acids (FFA) and RBO content which is insoluble in acetone make it difficult to process and is categorized as a low-quality oil, causing RBO to be only used as biodiesel feedstock. Enzymatic catalytic route for glycerolysis of vegetable oil offers milder operating conditions and higher product selectivity (MAG) but it has high production costs and long processing time. In this study, biodegradable catalysts were used, namely deep eutectic solvents (DES) based on phosponium and choline chloride for glycerolysis of dewaxed/degummed RBO (DDRBO) assisted with microwave irradiation. Effects of different types of DES catalysts (phosphonium and choline chloride based DES) on DES-catalyzed glycerolysis of low quality oil will be evaluated using 5%wt of DES, 300 W(150°C) for about 15 minutes. Out of the four DESs used, DES [TBAB][PTSAM] and DES [ChCl][AcAd] both showed outstanding catalytic performance. Especially [ChCl][AcAd] as a reaction catalyst for DDRBO glycerolysis showed the best catalytic activity, and high selectivity for the formation of monoglycerides (MG). Meanwhile [TBAB][PTSAM] showed high selectivity (92.57%) for diglyceride (DG) formation.
单甘油酯 (MAG) 和双甘油酯 (DAG) 在食品、制药和化妆品行业有着广泛的应用。尽管从植物油中生产这类乳化剂具有经济竞争力，但人们对高营养价值产品的需求不断增长，使得米糠油（RBO）等某些类型的健康油成为生产优质油脂的潜在原料，以满足这一不断增长的市场需求。然而，高游离脂肪酸（FFA）和不溶于丙酮的米糠油含量使其难以加工，被归类为低质油，导致米糠油只能用作生物柴油原料。利用酶催化路线对植物油进行甘油分解可提供更温和的操作条件和更高的产品选择性（MAG），但其生产成本高、加工时间长。本研究使用了生物可降解催化剂，即基于磷酸盐和氯化胆碱的深共晶溶剂（DES），在微波辐照辅助下用于脱蜡/脱胶 RBO（DDRBO）的甘油分解。在使用 5%重量的 DES、300 W（150°C）、约 15 分钟的条件下，将评估不同类型的 DES 催化剂（基于磷和氯化胆碱的 DES）对 DES 催化低质油甘油分解的影响。在使用的四种 DES 中，DES [TBAB][PTSAM]和 DES [ChCl][AcAd] 均表现出优异的催化性能。尤其是[ChCl][AcAd]作为DDRBO甘油分解反应催化剂，其催化活性最好，对单甘油酯（MG）的生成具有很高的选择性。同时，[TBAB][PTSAM]对二甘油酯（DG）的生成具有较高的选择性（92.57%）。
{"title":"Application of Phosphonium- and Choline Chloride Based Deep Eutectic Solvents as Catalyst for Emulsifier Production from Low Quality Oil Assisted by Microwave Irradiation","authors":"Miranda Amiroh Sulaiman, S. Zullaikah, Hoo Peng Yong, A. Quitain","doi":"10.4028/p-o1zllv","DOIUrl":"https://doi.org/10.4028/p-o1zllv","url":null,"abstract":"Monoglycerides (MAG) and Diglycerides (DAG) have wide applications in the food, pharmaceutical and cosmetic industries. Despite the economic competitiveness of producing this type of emulsifier from vegetable oils, the increasing demand for products with high nutritional value makes certain types of healthy oils such as rice bran oil (RBO) a potential raw material for high quality fats to serve this growing market. However, the high free fatty acids (FFA) and RBO content which is insoluble in acetone make it difficult to process and is categorized as a low-quality oil, causing RBO to be only used as biodiesel feedstock. Enzymatic catalytic route for glycerolysis of vegetable oil offers milder operating conditions and higher product selectivity (MAG) but it has high production costs and long processing time. In this study, biodegradable catalysts were used, namely deep eutectic solvents (DES) based on phosponium and choline chloride for glycerolysis of dewaxed/degummed RBO (DDRBO) assisted with microwave irradiation. Effects of different types of DES catalysts (phosphonium and choline chloride based DES) on DES-catalyzed glycerolysis of low quality oil will be evaluated using 5%wt of DES, 300 W(150°C) for about 15 minutes. Out of the four DESs used, DES [TBAB][PTSAM] and DES [ChCl][AcAd] both showed outstanding catalytic performance. Especially [ChCl][AcAd] as a reaction catalyst for DDRBO glycerolysis showed the best catalytic activity, and high selectivity for the formation of monoglycerides (MG). Meanwhile [TBAB][PTSAM] showed high selectivity (92.57%) for diglyceride (DG) formation.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139775166","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}
Putera Anugrah Dhira Atmaja Perdana, H. Sulistyo, M. M. Azis
Glycerol is an important chemical and widely used in many applications. Glycerol can be produced from a biodiesel industry as a by-product. In order to improve the economic value of glycerol as a by-product, it can be reacted with acetone to form solketal. Solketal can be used as a fuel additive to increase octane number. Reaction between glycerol and acetone can be catalyzed by Amberlyst-36. The objective of present study was to investigate the effect of mole ratio of glycerol:acetone and reaction temperature to the glycerol conversion. The process of acetalization was conducted in a batch reactor equipped with heater, temperature control, cooler and stirrer. The weight of catalyst was set on 5% based mass of glycerol and the stirrer speed was set on 650 rpm with reaction time of 3 hours. The mole ratio of glycerol to acetone was varied at 1:3, 1:4, 1:5 and 1:6, and the temperatures were varied on 40, 50 and 55 °C. The results showed that the highest conversion was 86.61 %, which was obtained at 120 minutes reaction, 50 °C and 1:6 mole ratio.
{"title":"Solketal Reaction Optimization by Glycerol Acetalization Using Amberlyst-36 Catalyst","authors":"Putera Anugrah Dhira Atmaja Perdana, H. Sulistyo, M. M. Azis","doi":"10.4028/p-kiw3er","DOIUrl":"https://doi.org/10.4028/p-kiw3er","url":null,"abstract":"Glycerol is an important chemical and widely used in many applications. Glycerol can be produced from a biodiesel industry as a by-product. In order to improve the economic value of glycerol as a by-product, it can be reacted with acetone to form solketal. Solketal can be used as a fuel additive to increase octane number. Reaction between glycerol and acetone can be catalyzed by Amberlyst-36. The objective of present study was to investigate the effect of mole ratio of glycerol:acetone and reaction temperature to the glycerol conversion. The process of acetalization was conducted in a batch reactor equipped with heater, temperature control, cooler and stirrer. The weight of catalyst was set on 5% based mass of glycerol and the stirrer speed was set on 650 rpm with reaction time of 3 hours. The mole ratio of glycerol to acetone was varied at 1:3, 1:4, 1:5 and 1:6, and the temperatures were varied on 40, 50 and 55 °C. The results showed that the highest conversion was 86.61 %, which was obtained at 120 minutes reaction, 50 °C and 1:6 mole ratio.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139775970","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}
The thermal stability of composite materials based on basalt fibers is determined by the strength of fibers under thermal stress. The decrease in strength occurs due to the crystallization of the original fibers and the development of microcrystalline nuclei in them during heating. Experimental studies of the influence of the processing temperature of continuous basalt fibers on their strength have been carried out. It has been established that the strength of fibers during their heat treatment up to 400оС decreases by 25 % from the initial one. At the temperature of approximately 500оС, the strength of the fibers is almost half. At 600оС, the fiber strength is 20 % of the initial strength. At a processing temperature of 700оС, the fiber is completely destroyed. The main reasons for the decrease in fiber strength are the development of microcrystalline nuclei that have formed in the fibers at the drawing stage in the crystallization zone. From above, this zone is determined by the temperature of the upper limit of melt crystallization, and from below it is limited by the glass transition temperature. The residence time of the melt in this range is the crystallization time. Calculations the speed of movement and the cooling rate of the melt stream during fiber drawing were carried out, which made it possible to determine the temperature zone and time of crystallization. The results of theoretical studies have shown that for the production of fibers used in composites, it is necessary to select such basalts and conditions for the fiber drawing, under which the values of the temperature zone and time of crystallization will be the smallest.
{"title":"Effect of Crystallization Properties of Continuous Basalt Fibers on Thermal Stability of Composite Materials","authors":"S. Ivanitskii, Yurii Chuvashov","doi":"10.4028/p-unbrc9","DOIUrl":"https://doi.org/10.4028/p-unbrc9","url":null,"abstract":"The thermal stability of composite materials based on basalt fibers is determined by the strength of fibers under thermal stress. The decrease in strength occurs due to the crystallization of the original fibers and the development of microcrystalline nuclei in them during heating. Experimental studies of the influence of the processing temperature of continuous basalt fibers on their strength have been carried out. It has been established that the strength of fibers during their heat treatment up to 400оС decreases by 25 % from the initial one. At the temperature of approximately 500оС, the strength of the fibers is almost half. At 600оС, the fiber strength is 20 % of the initial strength. At a processing temperature of 700оС, the fiber is completely destroyed. The main reasons for the decrease in fiber strength are the development of microcrystalline nuclei that have formed in the fibers at the drawing stage in the crystallization zone. From above, this zone is determined by the temperature of the upper limit of melt crystallization, and from below it is limited by the glass transition temperature. The residence time of the melt in this range is the crystallization time. Calculations the speed of movement and the cooling rate of the melt stream during fiber drawing were carried out, which made it possible to determine the temperature zone and time of crystallization. The results of theoretical studies have shown that for the production of fibers used in composites, it is necessary to select such basalts and conditions for the fiber drawing, under which the values of the temperature zone and time of crystallization will be the smallest.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139834167","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}
Oleksii Burlachenko, N. Vigilianska, Cezary Senderowski
The paper presents a study of the formation process of cermet powders based on TiAl intermetallic with the addition of non-metallic refractory compounds. Non-metallic refractory compounds B4C, BN, SiC, and Si3N4 were chosen as strengthening components, improving the mechanical properties and resistance to high-temperature oxidation of TiAl-type intermetallic coatings. The composition of the initial mixtures was selected based on thermodynamic analysis of the interaction between TiAl intermetallic and non-metallic refractory compounds. As a result of the mechanochemical synthesis of powder mixtures, 73TiAl-27B4C, 69TiAl-31BN, 88TiAl-12SiC, and 83TiAl-17Si3N4 (wt. %) cermet powders are formed, consisting of titanium aluminide (TiAl, Ti3Al) phases and refractory compounds of aluminium (AlB2 and AlN) and titanium (TiB2, TiC, TiN, Ti5Si3). The conglomeration technology of produced cermet powders has been developed to enhance fluidity. Using conglomerated powders will provide their constant feed to the high-temperature jet and the formation of dense coatings during thermal spraying.
本文研究了添加非金属耐火化合物的基于 TiAl 金属间化合物的金属陶瓷粉末的形成过程。非金属耐火化合物 B4C、BN、SiC 和 Si3N4 被选为强化成分，可改善 TiAl 型金属间化合物涂层的机械性能和抗高温氧化性。初始混合物的成分是根据 TiAl 金属间化合物和非金属耐火化合物之间相互作用的热力学分析选定的。通过粉末混合物的机械化学合成，形成了 73TiAl-27B4C、69TiAl-31BN、88TiAl-12SiC 和 83TiAl-17Si3N4（重量百分比）的金属陶瓷粉末，由铝化钛（TiAl、Ti3Al）相和铝（AlB2 和 AlN）及钛（TiB2、TiC、TiN、Ti5Si3）的耐火化合物组成。为提高流动性，已开发出生产金属陶瓷粉末的凝结技术。在热喷涂过程中，使用聚结粉末可为高温喷射提供稳定的进料，并形成致密的涂层。
{"title":"Cermet Powders Based on TiAl Intermetallic for Thermal Spraying","authors":"Oleksii Burlachenko, N. Vigilianska, Cezary Senderowski","doi":"10.4028/p-7ris3b","DOIUrl":"https://doi.org/10.4028/p-7ris3b","url":null,"abstract":"The paper presents a study of the formation process of cermet powders based on TiAl intermetallic with the addition of non-metallic refractory compounds. Non-metallic refractory compounds B4C, BN, SiC, and Si3N4 were chosen as strengthening components, improving the mechanical properties and resistance to high-temperature oxidation of TiAl-type intermetallic coatings. The composition of the initial mixtures was selected based on thermodynamic analysis of the interaction between TiAl intermetallic and non-metallic refractory compounds. As a result of the mechanochemical synthesis of powder mixtures, 73TiAl-27B4C, 69TiAl-31BN, 88TiAl-12SiC, and 83TiAl-17Si3N4 (wt. %) cermet powders are formed, consisting of titanium aluminide (TiAl, Ti3Al) phases and refractory compounds of aluminium (AlB2 and AlN) and titanium (TiB2, TiC, TiN, Ti5Si3). The conglomeration technology of produced cermet powders has been developed to enhance fluidity. Using conglomerated powders will provide their constant feed to the high-temperature jet and the formation of dense coatings during thermal spraying.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139776091","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}
Abdul Hapid, S. Zullaikah, M. Mahfud, A. Kawigraha
Reserves of high-grade gold ore worldwide are decreasing, and some industries have started processing refractory gold ore. Refractory gold ore contains sulfide minerals such as pyrite (FeS2), chalcopyrite (CuFeS2), galena (PbS), and sphalerite (ZnS). Gold in refractory ores occurs as fine-size gold-bearing sulfide minerals. In this study, the microwave-assisted roasting method has been investigated as a pretreatment for a refractory gold ore. This method can provide rapid heating radiation, cause micro-cracks, and trigger the decomposition of sulfide minerals. The presence of additive helps in the oxidation of sulfide minerals. The microwave-assisted roasting was carried out using variations in microwave power and time. Microwave power between 300 - 600 watts significantly affected the increase in roasting temperature and weight loss of refractory gold ore. The highest temperature reached 567°C in roasting at 800 watts for 30 minutes. The optimum condition for microwave roasting was achieved at 400 watts of power with a roasting time of 30 minutes. Metals extraction of Cu, Zn, Pb, and Fe reached 97.2%, 82.7%, 16.1%, and 2.1% in water leaching.
{"title":"Effect of Power and Exposure Time on the Microwave-Assisted Roasting of Refractory Gold Ore","authors":"Abdul Hapid, S. Zullaikah, M. Mahfud, A. Kawigraha","doi":"10.4028/p-l8nrjw","DOIUrl":"https://doi.org/10.4028/p-l8nrjw","url":null,"abstract":"Reserves of high-grade gold ore worldwide are decreasing, and some industries have started processing refractory gold ore. Refractory gold ore contains sulfide minerals such as pyrite (FeS2), chalcopyrite (CuFeS2), galena (PbS), and sphalerite (ZnS). Gold in refractory ores occurs as fine-size gold-bearing sulfide minerals. In this study, the microwave-assisted roasting method has been investigated as a pretreatment for a refractory gold ore. This method can provide rapid heating radiation, cause micro-cracks, and trigger the decomposition of sulfide minerals. The presence of additive helps in the oxidation of sulfide minerals. The microwave-assisted roasting was carried out using variations in microwave power and time. Microwave power between 300 - 600 watts significantly affected the increase in roasting temperature and weight loss of refractory gold ore. The highest temperature reached 567°C in roasting at 800 watts for 30 minutes. The optimum condition for microwave roasting was achieved at 400 watts of power with a roasting time of 30 minutes. Metals extraction of Cu, Zn, Pb, and Fe reached 97.2%, 82.7%, 16.1%, and 2.1% in water leaching.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139834054","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}
Yuriy Nikitenko, Viktor Shapovalov, Volodymyr Yakusha, O. Gnizdylo, Olena M. Berdnikova
The results of the development of the technology for growing super-large single crystals of refractory metals, which were developed at the E.O. Paton Electric Welding Institute of the NAS of Ukraine. Based on proven technology and acquired skills, a new generation of equipment was created that allows the growth of single crystals of refractory alloys in the form of bodies of rotation. Experiments were conducted on growing a single crystal of tungsten in the form of a hollow cylinder, from which it is possible to make such a product as a crucible. Technological parameters and energy regimes were established, which allowed for control of the thickness of the wall to be welded. As a result of the experiments, an ingot with a welded wall height of 68 mm, a thickness of 20–22 mm, and an outer diameter of 85 mm was grown. The structure of the obtained samples was studied.
乌克兰国家航空和航天局帕顿电焊研究所（E.O. Paton Electric Welding Institute of the NAS of Ukraine）研发的超大型难熔金属单晶体生长技术的成果。在成熟技术和已掌握技能的基础上，研发出了新一代设备，可以旋转体的形式生长难熔合金单晶体。进行了以空心圆柱体形式生长钨单晶体的实验，由此可以制造坩埚等产品。建立了技术参数和能量机制，从而可以控制焊接壁的厚度。实验结果表明，钢锭的焊接壁高为 68 毫米，厚度为 20-22 毫米，外径为 85 毫米。对所获得样品的结构进行了研究。
{"title":"Features of the Structural Formation of Tungsten Single Crystals in the Shape of Hollow Rotational Bodies","authors":"Yuriy Nikitenko, Viktor Shapovalov, Volodymyr Yakusha, O. Gnizdylo, Olena M. Berdnikova","doi":"10.4028/p-sdyx6a","DOIUrl":"https://doi.org/10.4028/p-sdyx6a","url":null,"abstract":"The results of the development of the technology for growing super-large single crystals of refractory metals, which were developed at the E.O. Paton Electric Welding Institute of the NAS of Ukraine. Based on proven technology and acquired skills, a new generation of equipment was created that allows the growth of single crystals of refractory alloys in the form of bodies of rotation. Experiments were conducted on growing a single crystal of tungsten in the form of a hollow cylinder, from which it is possible to make such a product as a crucible. Technological parameters and energy regimes were established, which allowed for control of the thickness of the wall to be welded. As a result of the experiments, an ingot with a welded wall height of 68 mm, a thickness of 20–22 mm, and an outer diameter of 85 mm was grown. The structure of the obtained samples was studied.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139834794","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}
Putera Anugrah Dhira Atmaja Perdana, H. Sulistyo, M. M. Azis
Glycerol is an important chemical and widely used in many applications. Glycerol can be produced from a biodiesel industry as a by-product. In order to improve the economic value of glycerol as a by-product, it can be reacted with acetone to form solketal. Solketal can be used as a fuel additive to increase octane number. Reaction between glycerol and acetone can be catalyzed by Amberlyst-36. The objective of present study was to investigate the effect of mole ratio of glycerol:acetone and reaction temperature to the glycerol conversion. The process of acetalization was conducted in a batch reactor equipped with heater, temperature control, cooler and stirrer. The weight of catalyst was set on 5% based mass of glycerol and the stirrer speed was set on 650 rpm with reaction time of 3 hours. The mole ratio of glycerol to acetone was varied at 1:3, 1:4, 1:5 and 1:6, and the temperatures were varied on 40, 50 and 55 °C. The results showed that the highest conversion was 86.61 %, which was obtained at 120 minutes reaction, 50 °C and 1:6 mole ratio.
{"title":"Solketal Reaction Optimization by Glycerol Acetalization Using Amberlyst-36 Catalyst","authors":"Putera Anugrah Dhira Atmaja Perdana, H. Sulistyo, M. M. Azis","doi":"10.4028/p-kiw3er","DOIUrl":"https://doi.org/10.4028/p-kiw3er","url":null,"abstract":"Glycerol is an important chemical and widely used in many applications. Glycerol can be produced from a biodiesel industry as a by-product. In order to improve the economic value of glycerol as a by-product, it can be reacted with acetone to form solketal. Solketal can be used as a fuel additive to increase octane number. Reaction between glycerol and acetone can be catalyzed by Amberlyst-36. The objective of present study was to investigate the effect of mole ratio of glycerol:acetone and reaction temperature to the glycerol conversion. The process of acetalization was conducted in a batch reactor equipped with heater, temperature control, cooler and stirrer. The weight of catalyst was set on 5% based mass of glycerol and the stirrer speed was set on 650 rpm with reaction time of 3 hours. The mole ratio of glycerol to acetone was varied at 1:3, 1:4, 1:5 and 1:6, and the temperatures were varied on 40, 50 and 55 °C. The results showed that the highest conversion was 86.61 %, which was obtained at 120 minutes reaction, 50 °C and 1:6 mole ratio.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139835584","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}
Aldrin Lalem, Jay C. Dulog, Jared Deve P. Delicana, Romnick B. Unabia, Noel Lito B. Sayson, R. Capangpangan, A. Lubguban, Arnold A. Alguno
Semiconductor-metal nanocomposites are actively investigated for their diverse applications in emerging fields such as photocatalysis, photovoltaics, and chemical sensing. In this study, we synthesized ZnO semiconductor nanoparticles using a chemical bath deposition method with ZnSO4·7H2O and controlled NH4OH concentrations, facilitated by an anionic surfactant to enable the attachment of Au metal nanoparticles. Au nanoparticles were prepared from HAuCl4 using citrate as a reducing agent, and metal oxide was rapidly introduced to ensure a well-defined nanocomposite with a fixed 75 w/v% composition. Fast Fourier transform spectroscopy (FTIR) and Ultra-visible (UV-Vis) spectroscopy were used to provide clear evidence of Au/ZnO nanocomposite formation through the presence of distinctive peaks around 359nm and 518nm, with Dynamic Light Scattering (DLS) revealing contrasting average sizes for ZnO and Au, highlighting the significant size difference in the Au/ZnO nanocomposites. Additionally, the scanning electron microscopy – energy dispersive x-ray (SEM-EDS) analysis confirmed the successful presence of ZnO nanoparticles. These findings offer insights into the potential applications and unique properties of Au/ZnO nanocomposites for possible photocatalytic applications.
{"title":"Synthesis and Characterization of Hierarchical Structure Au/ZnO Nanocomposites for Possible Photocatalytic Applications","authors":"Aldrin Lalem, Jay C. Dulog, Jared Deve P. Delicana, Romnick B. Unabia, Noel Lito B. Sayson, R. Capangpangan, A. Lubguban, Arnold A. Alguno","doi":"10.4028/p-piu3w7","DOIUrl":"https://doi.org/10.4028/p-piu3w7","url":null,"abstract":"Semiconductor-metal nanocomposites are actively investigated for their diverse applications in emerging fields such as photocatalysis, photovoltaics, and chemical sensing. In this study, we synthesized ZnO semiconductor nanoparticles using a chemical bath deposition method with ZnSO4·7H2O and controlled NH4OH concentrations, facilitated by an anionic surfactant to enable the attachment of Au metal nanoparticles. Au nanoparticles were prepared from HAuCl4 using citrate as a reducing agent, and metal oxide was rapidly introduced to ensure a well-defined nanocomposite with a fixed 75 w/v% composition. Fast Fourier transform spectroscopy (FTIR) and Ultra-visible (UV-Vis) spectroscopy were used to provide clear evidence of Au/ZnO nanocomposite formation through the presence of distinctive peaks around 359nm and 518nm, with Dynamic Light Scattering (DLS) revealing contrasting average sizes for ZnO and Au, highlighting the significant size difference in the Au/ZnO nanocomposites. Additionally, the scanning electron microscopy – energy dispersive x-ray (SEM-EDS) analysis confirmed the successful presence of ZnO nanoparticles. These findings offer insights into the potential applications and unique properties of Au/ZnO nanocomposites for possible photocatalytic applications.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139835938","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}
Jay C. Dulog, Romnick B. Unabia, Jared Deve P. Delicana, Aldrin Lalem, Noel Lito B. Sayson, R. Capangpangan, A. Lubguban, Arnold A. Alguno
Nanoparticles have been intensively studied due to their unique, size-dependent properties, paving the way for various applications, particularly in photocatalysis. This study aims to determine the physicochemical characteristics of TiO2 and Au nanoparticles and the AuNP/TiO2 hybrid nanoparticles. Employing multiple characterization techniques, the structural and functional parameters were elucidated. The Brunauer-Emmett-Teller (BET) surface area analysis revealed the pore sizes of TiO2 and the Au/TiO2 hybrid nanoparticles as 12 nm and 18 nm, respectively. The Dynamic light scattering (DLS) measurements revealed the hydrodynamic size of the AuNP/TiO2 hybrid nanoparticles at 386 nm. The UV-visible spectroscopy showed the absorbance peaks associated with their electronic structures and potential photocatalytic applications. The fast Fourier infrared (FTIR) spectroscopy results revealed the surface molecular interactions crucial for nanoparticle functionalities. The AuNP/TiO2 hybrid nanoparticles exhibit a larger pore size compared to TiO2NPs, indicating their superior adsorption capability. Moreover, the unique band gap of TiO2NPs and electron-hole pair generation make it a formidable candidate for photocatalysis. The incorporation of AuNPs may further augment charge separation, optimizing photocatalytic activity. These findings spotlight the promise of these AuNP/TiO2 hybrid nanoparticles in possible photocatalytic applications.
{"title":"Synthesis and Characterization of AuNP/TiO2 Hybrid Nanoparticles for Possible Photocatalytic Application","authors":"Jay C. Dulog, Romnick B. Unabia, Jared Deve P. Delicana, Aldrin Lalem, Noel Lito B. Sayson, R. Capangpangan, A. Lubguban, Arnold A. Alguno","doi":"10.4028/p-ogeu80","DOIUrl":"https://doi.org/10.4028/p-ogeu80","url":null,"abstract":"Nanoparticles have been intensively studied due to their unique, size-dependent properties, paving the way for various applications, particularly in photocatalysis. This study aims to determine the physicochemical characteristics of TiO2 and Au nanoparticles and the AuNP/TiO2 hybrid nanoparticles. Employing multiple characterization techniques, the structural and functional parameters were elucidated. The Brunauer-Emmett-Teller (BET) surface area analysis revealed the pore sizes of TiO2 and the Au/TiO2 hybrid nanoparticles as 12 nm and 18 nm, respectively. The Dynamic light scattering (DLS) measurements revealed the hydrodynamic size of the AuNP/TiO2 hybrid nanoparticles at 386 nm. The UV-visible spectroscopy showed the absorbance peaks associated with their electronic structures and potential photocatalytic applications. The fast Fourier infrared (FTIR) spectroscopy results revealed the surface molecular interactions crucial for nanoparticle functionalities. The AuNP/TiO2 hybrid nanoparticles exhibit a larger pore size compared to TiO2NPs, indicating their superior adsorption capability. Moreover, the unique band gap of TiO2NPs and electron-hole pair generation make it a formidable candidate for photocatalysis. The incorporation of AuNPs may further augment charge separation, optimizing photocatalytic activity. These findings spotlight the promise of these AuNP/TiO2 hybrid nanoparticles in possible photocatalytic applications.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139834375","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}
Miranda Amiroh Sulaiman, S. Zullaikah, Hoo Peng Yong, A. Quitain
Monoglycerides (MAG) and Diglycerides (DAG) have wide applications in the food, pharmaceutical and cosmetic industries. Despite the economic competitiveness of producing this type of emulsifier from vegetable oils, the increasing demand for products with high nutritional value makes certain types of healthy oils such as rice bran oil (RBO) a potential raw material for high quality fats to serve this growing market. However, the high free fatty acids (FFA) and RBO content which is insoluble in acetone make it difficult to process and is categorized as a low-quality oil, causing RBO to be only used as biodiesel feedstock. Enzymatic catalytic route for glycerolysis of vegetable oil offers milder operating conditions and higher product selectivity (MAG) but it has high production costs and long processing time. In this study, biodegradable catalysts were used, namely deep eutectic solvents (DES) based on phosponium and choline chloride for glycerolysis of dewaxed/degummed RBO (DDRBO) assisted with microwave irradiation. Effects of different types of DES catalysts (phosphonium and choline chloride based DES) on DES-catalyzed glycerolysis of low quality oil will be evaluated using 5%wt of DES, 300 W(150°C) for about 15 minutes. Out of the four DESs used, DES [TBAB][PTSAM] and DES [ChCl][AcAd] both showed outstanding catalytic performance. Especially [ChCl][AcAd] as a reaction catalyst for DDRBO glycerolysis showed the best catalytic activity, and high selectivity for the formation of monoglycerides (MG). Meanwhile [TBAB][PTSAM] showed high selectivity (92.57%) for diglyceride (DG) formation.
单甘油酯 (MAG) 和双甘油酯 (DAG) 在食品、制药和化妆品行业有着广泛的应用。尽管从植物油中生产这类乳化剂具有经济竞争力，但人们对高营养价值产品的需求不断增长，使得米糠油（RBO）等某些类型的健康油成为生产优质油脂的潜在原料，以满足这一不断增长的市场需求。然而，高游离脂肪酸（FFA）和不溶于丙酮的米糠油含量使其难以加工，被归类为低质油，导致米糠油只能用作生物柴油原料。利用酶催化路线对植物油进行甘油分解可提供更温和的操作条件和更高的产品选择性（MAG），但其生产成本高、加工时间长。本研究使用了生物可降解催化剂，即基于磷酸盐和氯化胆碱的深共晶溶剂（DES），在微波辐照辅助下用于脱蜡/脱胶 RBO（DDRBO）的甘油分解。在使用 5%重量的 DES、300 W（150°C）、约 15 分钟的条件下，将评估不同类型的 DES 催化剂（基于磷和氯化胆碱的 DES）对 DES 催化低质油甘油分解的影响。在使用的四种 DES 中，DES [TBAB][PTSAM]和 DES [ChCl][AcAd] 均表现出优异的催化性能。尤其是[ChCl][AcAd]作为DDRBO甘油分解反应催化剂，其催化活性最好，对单甘油酯（MG）的生成具有很高的选择性。同时，[TBAB][PTSAM]对二甘油酯（DG）的生成具有较高的选择性（92.57%）。
{"title":"Application of Phosphonium- and Choline Chloride Based Deep Eutectic Solvents as Catalyst for Emulsifier Production from Low Quality Oil Assisted by Microwave Irradiation","authors":"Miranda Amiroh Sulaiman, S. Zullaikah, Hoo Peng Yong, A. Quitain","doi":"10.4028/p-o1zllv","DOIUrl":"https://doi.org/10.4028/p-o1zllv","url":null,"abstract":"Monoglycerides (MAG) and Diglycerides (DAG) have wide applications in the food, pharmaceutical and cosmetic industries. Despite the economic competitiveness of producing this type of emulsifier from vegetable oils, the increasing demand for products with high nutritional value makes certain types of healthy oils such as rice bran oil (RBO) a potential raw material for high quality fats to serve this growing market. However, the high free fatty acids (FFA) and RBO content which is insoluble in acetone make it difficult to process and is categorized as a low-quality oil, causing RBO to be only used as biodiesel feedstock. Enzymatic catalytic route for glycerolysis of vegetable oil offers milder operating conditions and higher product selectivity (MAG) but it has high production costs and long processing time. In this study, biodegradable catalysts were used, namely deep eutectic solvents (DES) based on phosponium and choline chloride for glycerolysis of dewaxed/degummed RBO (DDRBO) assisted with microwave irradiation. Effects of different types of DES catalysts (phosphonium and choline chloride based DES) on DES-catalyzed glycerolysis of low quality oil will be evaluated using 5%wt of DES, 300 W(150°C) for about 15 minutes. Out of the four DESs used, DES [TBAB][PTSAM] and DES [ChCl][AcAd] both showed outstanding catalytic performance. Especially [ChCl][AcAd] as a reaction catalyst for DDRBO glycerolysis showed the best catalytic activity, and high selectivity for the formation of monoglycerides (MG). Meanwhile [TBAB][PTSAM] showed high selectivity (92.57%) for diglyceride (DG) formation.","PeriodicalId":507742,"journal":{"name":"Materials Science Forum","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139834742","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}
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