IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)
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Preparation And Characterization Of Cr/Activated Carbon Catalyst From Palm Empty Fruit Bunch
No full textPreparation and characterization of Cr/activated carbon catalyst from palm empty fruit bunch had been done. The research were to determine the effect of carbonization temperature towards adsorption of ammonia, iodine number, metilen blue number, and porosity of activated carbon and Cr/activated carbon catalyst. The determination of porosity include surface area, micropore volume and total pore volume. The results showed the best carbonization temperature activated carbon and Cr/activated carbon catalyst at 700°C. The adsorption ammonia of activated carbon and Cr/activated carbon catalyst as 6.379 mmol/g and 8.1624 mmol/g. The iodine number of activated carbon and Cr/activated carbon catalyst as 1520.16 mg/g and 1535.67 mg/g. The metilen blue number of activated carbon and Cr/activated carbon catalyst as 281.71 mg/g and 319.18 mg/g. The surface area of activated carbon and Cr/activated carbon catalyst as 1527.80 m2/g and 1652.58 m2/g. The micropore volume of activated carbon and Cr/activated carbon catalyst as 0.7460 cm3/g and 0.8670 cm3/g. The total pore volume of activated carbon and Cr/activated carbon catalyst as 0.8243 cm3/g and 0.8970 cm3/g.Keywords : activated carbon, palm empty fruit bunch, porosity, catalyst, chromiu
The Seasional Trends of Dissolved Oxygen and pH in Sugihan River, South Sumatra, Indonesia
Get PDFAbstract: The concentrations of DO and pH of Sugihan Rivers from the upstream at Riding, Pangkalan Lampam, OKI to the offshore region of Sugihan Estuary were analyzed at 15 sampling points during dry and rainy seasion. All measurements of DO and pH were direct analysis at the river stream. The concentrations as the average values of DO in dry seasion was 1,97 mg / L while in rainy seasion was 2,57 mg / L, and for the pH degree was 3,63 in dry seasion and 4,04 in rainy seasion, respectively. Based on the DO and pH values, this study shown the natural forests and peat lands gave contribution to the low of pH degree. The low of DO values also influenced by the pH, because decomposition in the peatlands made higher solubility of biomass to the rivers stream and decreasing the ability of oxygen to penetration into the waterbody.Keywords: DO, pH, Sugihan river, natural forest, peatland Abstrak (Indonesian): Konsentrasi DO dan pH Sungai Sugihan dari hulu di Kuda, Pangkalan Lampam, OKI ke wilayah lepas pantai Sugihan Muara dianalisis pada 15 titik sampling selama musim kering dan hujan. Semua pengukuran DO dan pH adalah analisis langsung di aliran sungai. Konsentrasi sebagai nilai rata-rata DO di musim kering adalah 1,97 mg / L sedangkan di musim hujan adalah 2,57 mg / L, dan untuk tingkat pH adalah 3,63 di seasion kering dan 4,04 di musim hujan. Berdasarkan nilai-nilai DO dan pH, penelitian ini menunjukkan bahwa hutan alam dan lahan gambut berkontribusi pada rendahnya tingkat pH. Rendahnya nilai DO juga dipengaruhi oleh pH, karena dekomposisi di lahan gambut membuat kelarutan yang lebih tinggi dari biomassa ke aliran sungai dan penurunan kemampuan oksigen untuk penetrasi ke aliran sungai tersebut. Kata kunci: DO, pH, Sungai Sugihan, hutan alam, lahan gambu
Isolation of Triterpenoid from Katemas (Euphorbia geniculata Ortega) Stem Extracted using Methanol and Its Toxicity Test
Get PDFKatemas (Euphorbia geniculata Ortega) known as (Mexican) Fireplants, Painted Euphorbia, Japanese poinsettia is a plant belong to Euphorbiaceae or spurge family. Traditionally, this plant is used as furgative and treat dysentry. The aims of the research were to evaluate the toxicity and to isolate one of the triterpenoid extracted using methanol from the stem of this plant. The toxicity was evaluated by mortality test against armyworm larvae (Spodoptera litura). This assay was obtained by Methanol extraction at various concentrations (0, 1, 2, 3, 4 and 5%). The isolation process was conducted by series of work steps such as extraction, fractionation and purification. Structure elucidation was determined by spectroscopy techniques. Toxicity assay exhibited highest mortality at 5 % concentration with LC50 3,92%. Spectroscopy data analysis was able to identified a type of pentacyclic triterpenoid compound namely lupeol acetate.Keyword: Euphorbia geniculata Ortega, toxicity, lupeol acetat
Modification of Cellulose with 4.4 Diaminodiphenylether-O-Hydroxibenzaldehide as Adsorbent and Its Application for Adsorbing Metalic Ion of Cd2+ In Aqueous Solution
Get PDFThis research on the modification of cellulose using 4,4-diaminodiphenylether and o-hydroxybenzaldehyde and its application to adsorb Cd2+ in aqueous solution has been done. The adsorption studies of cellulose and modified cellulose were done by using batch technique. The cellulose and modified cellulose were characterized by FTIR. The FTIR spectra revealed characteristic bands of 1573 cm-1, 1280 cm-1, 3749 cm-1 and 1056 cm-1. It indicates function group of C=N, C=O, O-H and Si-OR bond, respectively. The FTIR spectra of cellulose and modified cellulose which interacted to Cd2+, it were indicated by the shift in wavenumber 3410 cm-1 to 3371 cm-1. This spectral shift indicating Cd2+ bound to OH-group. In this research, interaction between modified cellulose with Cd2+ confirmed by intensities spectral changes at 1620 cm-1. The adsorption capacity and energy from adsorption of Cd2+ ions toward cellulose were 71,43 mg/g and 4,142 kJ/mol, while toward modified cellulose were 55,56 mg/g and 0,13 kJ/mol, respectively. Keywords: cellulose, 4,4-diaminodiphenylether-o-hydroxybenzaldehyde, adsorption, Cd2
Production of Biodiesel from Esterification of Oil Recovered from Palm Oil Mill Effluent (POME) Sludge using Tungstated-Zirconia Composite Catalyst
Get PDFSolid acid catalyst prepared from tungsten and zirconium oxide composite had been characterized and evaluated on biodiesel production by esterification of low quality oils taken from POME sludge. Catalyst characterization was conducted using Scanning Electron Microscopy (SEM) and acidity test. Acidity test of catalyst resulted using Gravimetry method is 5.4 mole/g. Esterification to produce biodiesel using tungsten and zirconium oxide composite show increasing amount of catalyst used will also increased conversion percentage of biodiesel produced and reach optimum value at 10%. Catalyst:oil ratio used to produce optimum conversion is 8:1 which converted 74.88% oil to biodiesel.Keywords: Tungsten-Zirconia composite, POME Sludge, EsterificationAbstrak (Indonesian). Penelitian tentang preparasi dan karakterisasi katalis komposit tungsten dan zirkonium oksida serta aplikasinya untuk esterifikasi minyak hasil recovery limbah sludge industri kelapa sawit telah dilakukan. Karakterisasi katalis dilakukan dengan menggunakan SEM dan uji sifat keasaman. Sifat keasaman katalis didapat sebesar 5,4 mol/g dengan metode gravimetri. Hasil pembuatan biodiesel dengan menggunakan katalis komposit tungsten dan zirkonium oksida didapatkan bahwa semakin besar jumlah katalis yang digunakan semakin besar pula % konversi biodiesel yang dihasilkan dan optimum pada 10%. Sementara perbandingan jumlah metanol:minyak didapatkan nilai optimum pada perbandingan 8:1 dengan % konversi biodiesel sebesar 74,88%.Kata Kunci: Tungsten-Zirconia composite, POME Sludge, Esterifikasi
Analyses of Non-bonding Length, Partial Atomics Charge and Electrostatic Energy from Molecular Dynamics Simulation of Phospholipase A2 – Substrate
Get PDFAbstract: This paper reports molecular dynamics simulation of phospholipase A2 (PLA2)– substrate that has been done. Non-bonding length, partial atomic charge and electrostatic energy were used to evaluation the interaction between PLA2 and substrate. The research was subjected for three types of PLA2 of different sources, i.e, homo sapien, bovinus and porcinus, by using computer files of their molecular structures. The files with code 3elo, 1bp2, dan 1y6o were downloaded from protein data bank. Substrate structure can be found in 1y60 and was separated from its enzyme structure and docked into two other PLA2 structures for simulation purpose. Molecular dynamics simulations were done for 30000 steps with constant in number of molecules, volume and temperature (NVT). The results showed the existing of flip-flop mechanism as basic feature of PLA2 – substrate reactions. Interaction length analysis results indicated the presence of water molecules on the structures of 1bp2 and 3elo at the time of the simulation was completed. The existence of aspagine at the reaction site confirmed the theory that this amino acid is responsible for the survival of the reaction. the electrostatic energy increased substantially in the interaction after homo sapien PLA2 (3elo) and Bovinus (1bp2) with the substrate. Inverse effect took place in the PLA porcinus (1y6o).Keywords: flip flop, inflammation, in-silico, simulation Abstrak (Indonesian): Telah dilakukan penelitian tentang simulasi dinamika molekuler pada Situs Reaksi Phospholipase A2 (PLA2) dengan substratnya. Analisis panjang non-ikatan, muatan atom parsial dan energi elektrostatis digunakan untuk menilai interaksi antara PLA2 dan substratnya. Penelitian dilakukan pada tiga jenis sumber PLA2, yaitu homo sapien, bovinus dan porcinus dengan menggunakan file komputer untuk struktur molekul dengan kode 3elo, 1bp2, dan 1y6o. Pada file 1y60 terdapat struktur substrat yang dapat ditemukan secara alamiah. Kedua file lainnya tidak mengandung struktur molekul substrat. Simulasi dinamika molekul dilakukan untuk 30.000 langkah dengan konstan dalam jumlah molekul, volume dan suhu (NVT). Hasil penelitian menunjukkan keberadaan mekanisme flip-flop sebagai fitur dasar reaksi PLA2 - substrat. Hasil analisis panjang interaksi menunjukkan bahwa kehadiran molekul air pada struktur 1bp2 dan 3elo pada saat simulasi dilakukan. Keberadaan aspagine di lokasi reaksi menegaskan teori bahwa asam amino ini bertanggung jawab untuk kelangsungan hidup reaksi. energi elektrostatik meningkat secara substansial dalam interaksi setelah homo sapien PLA2 (3elo) dan Bovinus (1bp2) dengan substrat. efek terbalik terjadi di porcinus PLA (1y6o).Kata kunci: flip flop, inflamasi, peradangan, in-silico, simulas
Hydroxyapatite Coating on Alloys CoCrMo-TiN with Sol-Gel Method
Get PDFABSTRACTHydroxyapatite is synthesized by precipitation-sonification using calcium from field snail shell and powder phosphorus from (NH4)2HPO4. The calcium value was measured by atomic absorption spectrophotometer was 82.82%.The temperatures were varied on 600, 800, and 1000 oC to determine the best temperature of the coating. The best temperature was used to superimpose the HAp on the CoCrMo-TiN metal alloy using the modified sol-gel method. The layer on the metal alloy was identified with x-ray diffraction (XRD) and corrosion test. The XRD result showed that most of the CoCrMo-TiN metal alloy surface was coated by HAp. Beside HAp, there were several other phases such as calcium phosphate, carbonate apatite type A and type B. The best result of the corrosion test was showed in CoCrMo-TiN metal alloy coated with HAp with the smallest corrosion rate 0.0082 mpy.Keywords: hydroxyapatite, CoCrMo-TiN, precipitation-sonification, sol-gel modifie
Photodegradation of Permethrin using Photocatalyst Montmorillonite-TiO2
Get PDF Photocatalyst Montmorillonite-TiO2 was synthesized using template CTAB and natural clay for degradation of Permethrin. The porosity and crystalline phase of catalyst were evaluated using N2 sorption analyzer and XRD diffraction. Permethrin photodegradation was optimized by varying reactant volume, irradiation time and initial concentration. Montmorillonite enhanced by CTAB showed typical porosity i.e. specific surface area, pore radii and pore volume for layer material. It properties decreased as this host material was impregnated with TiO2. XRD diagram indicated that space between layers of Montmorillonite expanded up to 4.7 Å. The diffractogram also confirmed that TiO2 formed an Anatase phase instead of Rutile. Photodegradation conducted at several condition showed relatively low photocatalytic activity. The highest photodegradation was achieved at 50 mL of Permethrin with initial concentration 10 ppm and 100 minutes’ irradiation. Keywords: Permethrin, Photodegradation, Montmorillonite-TiO
Comparison of The Performance of Proton Exchange Membrane Fuel Cell (PEMFC) Electrodes with Different Carbon Powder Content and Methods of Manufacture
Get PDFAbstract: Carbon powder in the gas diffusion layer (GDL) contained in the membrane electrode assembly (MEA) has an important role in the flow of electrons and reactant gas. Meanwhile, the method of making the electrode is one of the many studies conducted to determine the most appropriate method to use. Comparative study of the performance of proton exchange membrane fuel cell (PEMFC) electrodes with different carbon powder content (vulcan XC-72) in the GDL and methods of manufacture of the electrode between casting and spraying method has been carried out. The spraying method consists of one layer and three layer of catalyst layer (CL). The content of carbon powder in the GDL as much as 3 mg cm-2 has a better performance compared to 1.5 mg cm-2 with an increase of 177.78% current density at 0.6 V. Meanwhile, the manufacture of CL with three-layer spraying method has better performance compared with one-layer spraying and casting method.Key words: casting method, spraying method, catalyst layer (CL), GDL.Abstrak (Indonesian): Serbuk karbon pada lapisan difusi gas (LDG) yang menyusun elektroda membran memiliki peran penting dalam mengatur aliran elektron dan gas reaktan. Pada sisi lain metoda pembuatan elektroda adalah salah satu dari banyak studi yang dilakukan untuk menentukan metoda yang paling sesuai yang dapat dikerjakan. Telah dikerjakan studi komparatif kinerja membran penukar proton pada elektroda sel bahan bakar dengan kandungan serbuk karbon (vulcan XC-72) dalam LDG yang bervariasi dan studi komparasi metoda pembuatan elektroda secara tuang dan semprot. Metoda semprot dikerjakan dalam dua variasi yakni pembuatan lapisan katalis (LK) satu dan tiga lapisan. Kandungan serbuk karbon dalam LDG hingga 3 mg cm-2 memiliki kinerja lebih baik dibanding 1,5 mg cm-2 dengan peningkatan kerapatan arus 17,78% pada 0,6 V. Pembuatan LK dengan metoda semprot tiga lapisan memperlihatkan kinerja terbaik dibanding metoda semprot satu lapisan dan metoda tuang.Kata kunci: metode casting, metode spraying, layer katalis, GD
Thermal Stability and Acidity of Silica Supported Keggin Type Polyoxometalate K4[-SiW12O40]•nH2O
Get PDFSilica supported polyoxometalate K4[a-SiW12O40]·nH2O was prepared systematically using tetraethyl ortho silicate by sol gel method to form K4[a-SiW12O40]·nH2O/Si. Compound K4[a-SiW12O40]·nH2O/Si was characterized by diffraction, spectroscopic, and acidity analyses follow by thermal activity test at higher temperature up to 600 oC. Analysis of FTIR spectrum showed all unique vibration of polyoxometalate K4[a-SiW12O40]·nH2O was appeared at wavenumber 800-1000 cm-1 before and after supporting process. Crystallinity of K4[a-SiW12O40]·nH2O and K4[a-SiW12O40]·nH2O/Si were also similar without changing Keggin structure. Compound K4[a-SiW12O40]·nH2O/Si showed higher acidity than K4[a-SiW12O40]·nH2O probably due to Lewis acidity species. Keggin structure of K4[a-SiW12O40]·nH2O/Si was still retained up to 600 oC showing thermal stability of K4[a-SiW12O40]·nH2O/Si at high temperature.Keyword : Keggin polyoxometalate, tetraethyl ortho silicate, thermal stability, acidit