|
:: Abstract List ::
Page 5 (data 121 to 128 of 128) | Displayed ini 30 data/page
<< PREV
1 2 3 4 5
| 121 |
Physical Chemistry |
ABS-35 |
|
SYNTHESIS AND CHARACTERIZATION OF ZINC OXIDE NANOPARTICLES (NPs) USING SOL-GEL METHOD
Selma Yasinta Agasi and Nazriati
Universitas Negeri Malang
Abstract
Abstract. ZnO nanoparticles (NPs) are an interesting material due to its unique properties and it have so many potential in many areas like gas sensor, UV absorption, semiconductor, antibacterial, and photocatalysis. In many times there are many methods of synthesis, like sol-gel method have some adavantages like crystalite size, distribution particle size, morphology shape and monodispersity are easy to control, condition reaction with low temperature, high homogeneity and high purities. High result from sol-gel processing needs some factors for controlling crystal size, distribution particle size, and morphology shape and monodispersity. Variation concentration of NaOH can be effected as the growth of nanomaterial because using NaOH as medium preparation, and can be used as stabilizer, and as a capping agent role to control growth rate for particle size. This research is can be achieved with main steps of: (1) Synthesis with sol-gel method that needs main precursor Zinc acetate dehydrate with adding variation concentration of NaOH, and then drying process in 80 degree Celcius for 1 hours, (2) Characterization for knowing final result of synthesis from XRD, XRF, SEM, UV-Vis DRS, dan FT-IR. Synthesis process can be said successing in XRD test similar with COD database Number. 1011258. Analyze result using SEM showing morphology of nanoparticles ZnO speric particles that agglomerate with distribution monodispersity of surface particles area, and range of particles size within 10-83 nm, and particles size distribution is 41 nm. From XRF analyzes results, showing high peak intensity within 94,25% of oxide compound showing that high percentage of ZnO. In FTIR results, it^s showed in fingerprint area for Zn-O wavenumber within 500 cm^-1. UV-Vis DRS analyzes result band-gap energy with ratio mass between precursor and NaOH are ratio 1:1 have 3,22 eV- ratio 1:2 have 3,12 eV- ratio 1:3 have 3,21 eV, and ratio 1:4 have 3,18 eV.
Keywords: ZnO Nanoparticles, sol-gel method
Share Link
| Plain Format
| Corresponding Author (Selma Yasinta Agasi)
|
| 122 |
Physical Chemistry |
ABS-37 |
|
Effect Of Mole Ratio Of KOH/Bentonite Catalyst For Conversion Of Waste Cooking Oil To Methyl Ester
Nur Ain Sharina Shukor,1, a) Noraini Hamzah,2
School of Chemistry and Environment, Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
Abstract
Biodiesel is a sustainable and clean burning fuel that can be a substitute for conventional diesel. However, the production of biodiesel requires a higher cost compared to the conventional diesel. Hence, the cost of production can be reduced by using waste cooking oil (WCO) as feedstock. In this study, the production of biodiesel was carried out from waste cooking oil (WCO) via transesterification process and KOH/bentonite catalyst was used as a heterogeneous catalyst. A different molar ratio of KOH/bentonite catalyst was synthesised by impregnation of bentonite with potassium hydroxide (KOH) at 60 degree celsius for 6 hours. The ratios between KOH and bentonite were 1:2, 1:3, 1:4, 1:5, and 1:6. The characterization of both raw bentonite and KOH/bentonite catalyst were done using Thermogravimetric Analysis (TGA), Brunauer, Emmett, and Teller (BET), X Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM). The decreasing of BET surface area in raw bentonite and KOH/bentonite and the presence of K2O phase in the XRD pattern indicates that there is a process of KOH impregnated bentonite. Moreover, from the analysis of SEM, it shows that the particle size between raw bentonite and KOH/bentonite is increasing due to the impregnation process. The high yield of FFA conversion was obtained at optimum molar ratio of KOH/bentonite 1:5, which was 27.55% under the reaction parameters of methanol to oil molar ratio of 6:1, the reaction temperature at 60 degree celsius, 3wt% of catalyst concentration, and a reaction time of 3 hours. Reusability test shows the performance of KOH/bentonite catalyst in the conversion of FFA was dropped from 27.55% to 13.73%. This research reveal the feedstock of waste cooking oil is a great potential to produce good quality of biodiesel.
Keywords: Biodiesel, Catalyst, KOH/Bentonite, Waste Cooking Oil, Transesterification
Share Link
| Plain Format
| Corresponding Author (NUR AIN SHARINA SHUKOR)
|
| 123 |
Physical Chemistry |
ABS-70 |
|
Experimental and Simulation Study of Curcumin Nanoemulsion Preparation Using Low Pressure Input in Microfluidic Technique
Zubaidah Ningsih1a, Sulastri1, Andri Saputra1, Ken Nahel Falsaveta1, Budi Kamulyan1, Agus Choiron2, Muhammad Syafa Adana2
1 Chemistry Depatment Faculty of Science, Universitas Brawijaya Malang Indonesia
2 Mechanical Engineering Department Faculty of Engineering, Universitas Brawijaya Malang Indonesia
a corresponding author : zubaidah[at]ub.ac.id
Abstract
Nanoemulsion is a system of colloidal particle which urges the rapid
development of delivery system for bioactive substance and drugs. Microfluidization is one of the methods that is often use in the formation of nanoemulsion. This study aims to compare two microfluidic design effectiveness in nanoemulsion production using low pressure input, 70 and 100 Psi. Two designs applied are Y-Z combination and multiple Y-Z combination. Nanoemulsion characteristics compared are particles size and polydispersity index which are measured using Particles Size Analyzer applying Dynamic Light Scattering (DLS) Techique. The morphology of the system is observed using digital light microscope. Simulation of fluid pressure and flow rate inside microfluidic channel is conducted using Computational Fluid Dynamic applying Ansys software. After 1-hour microfluidization using multiple Y-Z combination design at 70 Psi pressure, particle size obtained was 144 nm with polydispersity index of 0,212. Meanwhile, using Y-Z combination design at 100 Psi pressure, particle size obtained after 1 hour process was 135 nm with polydispersity index of 0,227. Comparing these results, multiple Y-Z microfluidics design is capable of producing similar particle size and polydispersity index with Y-Z combination design using lower pressure. The modeling results show that the velocity is increasing while the pressure is decreasing from the inlet to the outlet. The velocity increase is 400% and 500% and the pressure decreases by 99% and 90% in the Y-Z combination and multiple Y-Z combination designs respectively. In the multiple Y-Z combination design, there are more turns and space for interaction between the nanoemulsion components, thus, it is possible to increase the probability of rearrangement of the nanoemulsion components. Hence, the particle size is smaller even though the initial pressure applied is lower.
Keywords: microfluidic, Y-Z design, simulation, fluid pressure, flow rate, nanoemulsion
Share Link
| Plain Format
| Corresponding Author (Zubaidah Ningsih)
|
| 124 |
Renewable Energy and Fuel Cell |
ABS-9 |
|
Determination of The Efficiency Value of Dye Sensitized Solar Cell from The Photosynthetic Pigment Of Tropical Marine Microalgae Navicula sp. TAD
Ivon Telussa (a*), Eirene G. Fransina (a), Eka Rahmat Mahayani Anthonio Putera Lilipaly (b), Alfa Musa Imanuel Efruan (c)
a) Departement Chemistry, Faculty of Mathematics and Natural Science, Universitas Pattimura
*ivon_telussa[at]ymail.com
b) Departement Mechanical Engineering, Ambon State Polytechnic
c) Biochemistry Laboratory of Departement Chemistry, Faculty of Mathematics and Natural Science, Universitas Pattimura
Abstract
Solar cells using dyes as sensitizers continue to expand. Synthetic dye as sensitizing materials for synthesized solar cells have high production costs, are difficult to find, and can cause environmental pollution. Solar cells using photosynthetic pigments as cell sensitizers are a solution to this problem. In this research, we investigated the effect of photosynthetic pigment from the Navicula sp. TAD as a dye sensitized material on the efficiency of Dye Sensitized Solar Cell. To obtain high biomass, the Navicula sp. TAD was cultivated in a modified medium. Navicula sp. TAD has photosynthetic pigments consisting of chlorophyll and carotenois with the content of 8.570 and 2.581 g/mL, respectively. Solar cells using pigment crude extract, which are absorbed by TiO2 as electrodes have efficiency values of 4.475 x 10^-4
Keywords: Chlorophyll, Carotenoid, Dye-Sensitized Solar Cell, Navicula sp. TAD, Photosynthetic pigment
Share Link
| Plain Format
| Corresponding Author (Ivonne Telussa)
|
| 125 |
Renewable Energy and Fuel Cell |
ABS-59 |
|
Potential of Organic Solvents in Making Fuel Oil from Extracts of Liverworts (Marchantia polymorpha) Using the Soxhlet Method
Febriandari Annisa Murti, Rani Dwi Lestari, Daffa^ Rizal Dzulfaqaar Alauddin, Hania Damayanti, Gelar Elsya Aprillia Monica, Muhammad Rizqy Pangestu, and Nur^aini Kartikasari
Departement of Biology, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Semarang Street No.5, Sumbersari, Malang City, East Java 65145
Abstract
Demand for fuel oil from year to year has increased. So far, fossil fuels have been used which have consumption limits. Renewable materials are needed to replace the use of fossil fuels. Many natural materials have the potential to be used as fuel oil, one of which is liverwort. Liverworts have oil bodies which are intracellular organelles bounded by a single unit membrane containing lipophilic globules suspended in a proteinaceous matrix. The use of organic solvents such as n-hexane and chloroform proved to be able to extract oil because it has nonpolar properties. In this study, the extraction of oil using the soxhlet extraction method with organic solvents was then carried out by transetherification. There were 2 treatments using n-hexane and chloroform with 3 replications each.The results showed the presence of oil contained in liverworts and have potential as fuel.
Keywords: Fuel oil, Liverworts, Organic solvents
Share Link
| Plain Format
| Corresponding Author (Rani Dwi Lestari)
|
| 126 |
Renewable Energy and Fuel Cell |
ABS-66 |
|
Catalyst of Cd - Cr/Activited Natural Zeolite for Conversion Of Glycerol to Ethanol with Ultrasonic Assitance
Sumari, Sumari1), Ghina Wijayanti, Ririn Cahyanti dan Aman Santoso
Universitas Negeri Malang
Abstract
The purpose of this study was to determine the characteristics and the effectiveness of Cd/ZAA, Cr/ZAA, and Cd-Cr/ZAA catalysts on conversion process of glycerol to ethanol. Zeolite was activated using 1% HF and refluxed with 6 M HCl and 1 M NH4Cl. Catalysts of Cd/ZAA, Cr/ZAA, and Cd-Cr/ZAA are white granules with a size of 100 mesh. The Catalysts were characterize using XRD, XRF, surface area analysis, and catalyst acidity test. Conversion of glycerol to ethanol by ultrasonic assistance was done in various time of 2, 4, and 6 hours. The result of XRD characterization showed that natural zeolite is mordenite. Specific surface area of catalyst of Natural Zeolite, H-ZAA, Cd/ZAA, Cr/ZAA, and Cd-Cr/ZAA were 140.06, 129.66, 64,534, 126.348, and 135.218 m2/g respectively. The total acidity level of Activated Natural Zeolite, H-ZAA, Cd/ZAA, Cr/ZAA, and Cd-Cr/ZAA catalysts were 0.74, 1.41 , 0.49 , 0.47, and 0.43 mmol/g respectively. The highest glycerol conversion was obtained when Cd-Cr/ZAA catalyst was used and in a sonication time of 6 hours with yield of 43.84% wt ethanol.
Keywords: natural zeolite, catalyst, glycerol conversion, ethanol.
Share Link
| Plain Format
| Corresponding Author (Sumari Sumari)
|
| 127 |
Renewable Energy and Fuel Cell |
ABS-93 |
|
The Effect of Humidifier Temperature and Hydrogen Flow Rate on MEA Performance of PEMFC Using Pt/C and Pd-Co/C Catalyst
Dedi Rohendi 1,2,*), Nirwan Syarif 1,2) , Arsali 3), Dwi Hawa Yulianti 2), Nikea Ry Anjeli 1), Nyimas Febrika S. 2), Icha Amelia 2)
1) Universitas Sriwijaya, Faculty of Mathematic and Natural Sciences, Department of Chemistry, Jl. Palembang-Prabumulih Km 32, Indralaya, Ogan Ilir 30662, Indonesia
2) Universitas Sriwijaya, Center of Research Excellent in Fuel Cell and Hydrogen, Jl. Srijaya Negara, Palembang 30138, Indonesia
3) Universitas Sriwijaya, Faculty of Mathematic and Natural Sciences, Department of Physic, Jl. Palembang-Prabumulih Km 32, Indralaya, Ogan Ilir, Indonesia
Abstract
Keywords: PEMFC, Pd-Co/C, Humidifier Temperature, Hydrogen Gas Flow Rate
Share Link
| Plain Format
| Corresponding Author (Dedi Rohendi)
|
| 128 |
Renewable Energy and Fuel Cell |
ABS-117 |
|
The Conversion of CO2 to Methanol With Electrochemical Reduction Methods
Dedi Rohendi1,2*, Nirwan Syarif 1,2, Addy Rachmat1,2 , Dewi Mersitarini3, Dimas Ardiyanta3, RR. Whiny H. Erliana3, Isya Mahendra3, Dwi Hawa Yulianti2, Nyimas Febrika S2, Icha Amelia2, M. Ilyas Izzudin1, Balqis Hayati1
1 Universitas Sriwijaya, Faculty of Mathematic and Natural Sciences, Department of Chemistry, Jl. Palembang-Prabumulih Km 32, Indralaya, Ogan Ilir, Indonesia
2 Univesitas Sriwijaya, Center of Research Excellent in Fuel Cell and Hydrogen, Jl. Srijaya Negara, Palembang, Indonesia
3 CCUS Research, Upstream Research & Technology Innovation - PT Pertamina (Persero)
Abstract
The Conversion of CO2 to Methanol With Electrochemical Reduction Methods is carried out as an effort to reduce CO2 emissions. The method of converting CO2 to methanol that is currently being developed is an electrochemical reduction method using a membrane electrode assembly (MEA) as the reaction center. MEA consists of a Nafion-117 electrolyte membrane and two electrodes in the form of a cathode and anode. The metal catalyst Cu2O-ZnO/C was used as the active site of the cathode and the metal catalyst Pt/C as the active site of the anode. Specific parameters that are considered in this study are the applied voltage conditions of 0.6- 0.8- 1.0- 1,2- 1.4- 1.6- 1.8- 2.0(V), CO2 flow rate 60- 80- 100- 120- 140- 160 (mL/min) on single stack and 120- 160- 200- 240 (mL/min) on dual-stack and operating times of 2, 4, 6, 8 (hours). The maximum methanol percentage was obtained at a voltage condition of 1.8 V (17.72 % w/v). A voltage of 1.8 V is used in the conversion process with varying flow rates to produce methanol with the highest percentage at a flow rate of 120 mL/minute (34.34% w/v) in a single stack and 160 mL/minute (39.30 %w/v). ) on the double stack. In addition, the operating time with a duration of 8 hours showed the percentage of methanol in a double stack (42.62% w/v) and multi-stack (45.36 % w/v). Conversion of CO2 with increasing operating time results in a decrease in Faraday efficiency due to the heat generated in the electrolyzer. Faraday efficiency for double stack and multi-stack (1.8 V- 160 mL/min- 8 hours) has a value of 33.47 % and 15.84 %, respectively.
Keywords: CO2, Methanol, Cu2O-ZnO/C, Electrochemical Reduction, MEA
Share Link
| Plain Format
| Corresponding Author (Dedi Rohendi)
|
Page 5 (data 121 to 128 of 128) | Displayed ini 30 data/page
<< PREV
1 2 3 4 5
|
