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Effect of Calcium Carbonate as Filler at the Chitosan/Calcium Carbonate Composite Membrane Retno Rahayu Dinararum; Dian Permana; Lukman Atmaja
IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (241.691 KB) | DOI: 10.12962/j23546026.y2015i1.1154

Abstract

Chitosan; calcium carbonate; DMFC; thermal stability Membrane is the most important part of Direct Methanol Fuel Cell (DMFC) because of its function as a proton transfer. The purpose of this research was studying the effect of calcium carbonate filler to the performance of chitosan (CS)/Calcium Carbonate (CC) composite membrane using 0.02; 0.04; 0.06; 0.08; and 0.10 g of CC. In this study, CS/CC membranes showed high performance for DMFC application. The best concentration of CS/CC was obtained with 0.06 g of CC based on proton conductivity, methanol permeability, and TGA measurements.
Effect of Glutaraldehyde Concentration Variation toward Properties and Performance of Composite Membrane (Chi-Mmt) for DMFC Application Sudir Umar; Dian Permana; Lukman Atmaja
IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j23546026.y2015i1.1161

Abstract

Membrane CS/MMT-GA were synthesized by inversion phase method. In this study, CS as matrix, MMT as filler and GA as cross linking agent. CS-GA-MMT showed high performance as good candidate for DMFC. The best composition was obtained to CS/MMT-GA2 with highest proton conductivity and lower methanol permeability.
Synthesis N-Doped Activated Carbon from Sugarcane Bagasse for CO2 Adsorption Randy Yusuf Kurniawan; Irsandi Dwi Oka Kurniawan; Lukman Atmaja; Nurul Widiastuti
IPTEK The Journal for Technology and Science Vol 30, No 3 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v30i3.5469

Abstract

Nitrogen-doped activated carbon (SBACN) was synthesized from sugarcane bagasse waste as acarbon source and urea as nitrogen source through potassium hydroxide (KOH) activation for 2 h at high temperature via two step methods. The synthesized SBCN was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Fourier Transform Infrared (FTIR). The results showed that the SBCN has low degree crystallinity and graphitization with highly developed micropores due to synergistik activation effect of KOH and urea. These characteristics provide an important contribution to carbon dioxide adsorption capacity, which can reach up to 11,20% wt and this value is higher than pristine activated carbon. The results indicating that the presence of this nitrogen functionalities is found to have a beneficial influence on the carbon dioxide adsorption characteristic in standart condition and exhibit considerable potential in solid adsorption.
Modification of Chitosan-Chitosan Phtalate Anhydrides Matrices Lukman Atmaja; Herianus Manimoy; Lina Eka Arizka
IPTEK The Journal for Technology and Science Vol 30, No 3 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j20882033.v30i3.5504

Abstract

Chitin and chitosan are natural biopolymers on shrimp shells. Chitosan is used extensively as a raw material in various industries. The study aimed to extract chitin and chitosan from fanami shrimp skin through deproteinization, demineralization, and deastilation reactions and to modify the matrix to improve the physical properties. The results of the analysis of the FTIR chitin spectrum shows several major peaks at wave number 3446.91 cm-1 which showed the vibrations of bending secondary amide and amine (NH) secondary amides at 1654.98 cm-1 indicating the presence of vibration stretching CH. The results of the chitosan FTIR spectrum analysis shows symmetrical stretching vibrations at 3433.41 cm-1 due to overlapping OH and amines (NH), stretching vibrations of 1653.05 cm-1 caused by the propagation of C = O stretching and stretching vibrations of 1587.47 cm-1 indicating secondary amide. The results of the characterization with XRD shows that the extracted compounds were chitin and chitosan. In modifying the chitosan matrix, the spectra result show peak at 1656.91 - 1564.32 cm-1 indicating the presence of an amide group. New aromatic group peak found in the area of 1631.83 cm-1 which not found in chitosan. Diffract gram XRD from pure chitosan shows three highest peak peaks at 2θ equal to 609.2; 609.88 and 550 while chitosan-anhydrous modification shows a peak at 2θ equal to 609.8. The addition of anhydrous phthalates to chitosan has reduced its crystallinity which results in an increase in the hydrophilic characteristics of the membrane. The results of this study are expected to be one of the references in further research regarding the manufacture of phthalate chitosan-anhydrous based composite membranes for DMFC
An Experimental Study of the Addition of Air Mass Flow Rate Using a 30% Emulsion-Fueled Diesel Engine at High Load Rosid Rosid; Bambang Sudarmanta; Lukman Atmaja; Salih Özer
Automotive Experiences Vol 3 No 2 (2020)
Publisher : Automotive Laboratory of Universitas Muhammadiyah Magelang in collaboration with Association of Indonesian Vocational Educators (AIVE)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (780.63 KB) | DOI: 10.31603/ae.v3i2.3618

Abstract

The purpose of this study was to examine the addition of air mass flow rate into the combustion chamber using E30 emulsion fuel (Water 70% + Dex 30% + 2% surfactant tween 80 + span 80 ) on a Diamond DI 800 stationary diesel engine with an engine rotation of 1500 rpm. Characteristics evaluated using Combustion Analyze, and emissions measured with a Gas Analyzer. The results showed the addition of air mass flow rate affected engine performance and emissions with the engine power observed to have decreased by 0.016% while SFC and thermal efficiency increased by 2,077% and 33,053% respectively compared to diesel fuel. Moreover, the BMEP and exhaust temperature also decreased with the most optimum in BMEP found to be 0.02% and exhaust temperature at 285°C while diesel has 358°C. The analysis of the combustion process for E30 emulsion fuel with variations in the air mass flow rate added showed the peak cylinder pressure at high loads was at 0.018 kg/s at a pressure of 5.86 bar. Meanwhile, the optimum heat release rate at high loads was obtained at a variation of 0.013 kg/s. This, therefore, means adding air mass flow rate to the E30 emulsion fuel has the ability to improve performance and reduce engine emissions.
Synthesis and Characterization of Chitosan/Phosphotungstic Acid-Montmorillonite Modified by Silane for DMFC Membrane Dian Permana; Muhammad Purwanto; La Ode Ahmad Nur Ramadhan; Lukman Atmaja
Indonesian Journal of Chemistry Vol 15, No 3 (2015)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.057 KB) | DOI: 10.22146/ijc.21188

Abstract

Montmorillonite was functionalized by (3-glycidyloxypropyl) trimethoxy silane (GPTMS). Subsequently, chitosan (CS) membranes filled by GPTMS-modified montmorillonite particles were prepared and characterized by FTIR. The result of FTIR obtained the peak wavenumber of 2940, 1471 and 1390 cm-1 referring to vibration stretching of CH2, bending of CH2 and CH3 form epoxy groups in silane, respectively which indicated modification of montmorillonite by silane. Compared with the pure CS and CS/PWA-MMT membrane, these CS/PWA-MMT/Silane hybrid membranes show apparently high proton conductivity and the lower methanol permeability, which could be assigned to the better interfacial morphology and compatibility between chitosan matrix and GPTMS-modified montmorillonite. In all the prepared CS/PWA-MMT/Silane hybrid membranes, the CS membrane filled by 10% GPTMS-modified montmorillonite particles exhibits the highest proton conductivity and the lowest methanol permeability, which is 19.15 x 10-3 S.cm-1 at 80 °C and 4.33 x 10-8 cm2.s-1, respectively. The results imply that CS/PWA-MMT silane 10% membrane has better interaction of interfacial morphology and compatibility between chitosan matrix and GPTMS-modified montmorillonite particles.
CRYSTALLINE PHASE REACTIVITY IN THE SYNTHESIS OF FLY ASH-BASED GEOPOLYMER Lukman Atmaja; Hamzah Fansuri; Anggaria Maharani
Indonesian Journal of Chemistry Vol 11, No 1 (2011)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (710.099 KB) | DOI: 10.22146/ijc.21426

Abstract

Aluminosilicate, alkaline solution and fly ash from a power plant have been used to synthesize geopolymer at ambient temperature. SiO2/Al2O3 mole ratio of the starting materials was varied by the addition of pure, insoluble corundum and quartz. The geopolymer exhibited some differences in the ratio of initial reaction mixtures and that of final products. The corundum gave no influence to the compressive strength while the quartz at SiO2/Al2O3=4.0-6.0 produced significant change in the strength. The highest compressive strength achieved was 65 MPa. XRD using analysis Rietveld method proved that quartz has been found both in starting materials as well as in the geopolymer indicating the involvement of crystalline phases, to some extent, in geopolymerization process.
SYNTHESIS AND CHARACTERIZATION OF HDPE PLASTIC FILM FOR HERBICIDE CONTAINER USING FLY ASH CLASS F AS FILLER Yatim Lailun Ni’mah; Lukman Atmaja; Hendro Juwono
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (185.358 KB) | DOI: 10.22146/ijc.21497

Abstract

High Density Polyethylene (HDPE) plastic plays an important role in various applications, for example, it can be used as a container (bottle). Petrokimia Kayaku Company, a branch of Petrokimia Company of Gresik, produces herbicides using HDPE plastic bottles as their container. Those plastic bottles undergo degradation (kempot) for certain period of time. The aim of this research is to characterize and to synthesize the HDPE plastic film with class F fly ash as filler. The results expected from this research are producing the plastic with a better properties and durability. This research was initiated by taking the sample of HDPE plastic bottle and herbicides (containing Gramakuat, on active material parakuat dichloride) at Petrokimia Kayaku Company. Both the initial HDPE and the degraded bottles was analyzed their tensile strength and Fourier Transform-Infra Red (FTIR) spectral. The next step was to synthesize the HDPE plastic film using class F fly ash as filler and a coupling agent. The filler concentrations were 0%, 5%, 10%, 15%, and 20wt %. The best result was 5% filler concentration with tensile strength of 27.7 lbs. This HDPE film was then subjected to degradation test using pyridine solution with various concentrations (1%, 3% and 5%) for two weeks, thermal degradation at 100 °C for two weeks and chemical resistance by xylene with soak time variation of 24 h, 98 h and 168 h. The result of degradations test show that the value of tensile strength was decreased with the increase of filler consentration. The chemical resistance, however, was increased.
Combined Computational and Experimental Study the Effect of Doped Magnesium into Betanine-sensitized TiO2 Photoanode for Dye-Sensitized Solar Cells Application Yuly Kusumawati; Nanik Ismi Oktavianti; Linda Wati Oktavia; Nurul Widiastuti; Lukman Atmaja; Nur Izzati Abu Bakar; Nur Hadi
Indonesian Journal of Chemistry Vol 19, No 4 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (15.743 KB) | DOI: 10.22146/ijc.36861

Abstract

A preliminary study of the effect of magnesium-doped into betanine-sensitized TiO2 thin layers has been carried out computationally and experimentally. The computational calculation was performed to observe the effect of magnesium on the interaction molecular of betanine onto TiO2 surface, using Ti12O28H8 model cluster. It was found out that the distance of the oxygen on the anchoring site betanine with the Ti in TiO2/Mg cluster is shortercompare to that one in TiO2 cluster. This result confirms the bond between betanine and TiO2 is stronger in the case of Mg2+ incorporation. The Natural Population Calculation also confirms that the electron transport from betanine to the TiO2 is more facilitated after Mg2+ incorporation. These results are also supported by the HOMO-LUMO profile of TiO2-betanine and TiO2/Mg. The XRD and SEM measurement confirm those are no effect on the TiO2 structure and morphology with the incorporation of Mg2+. The thin-film UV-Vis measurement confirms there is a bandgap sift after the incorporation of Mg.
Analisis Kuat Tarik dan Elongasi Film Gelatin – Khitosan Abdul Wafi; Lukman Atmaja; Yatim Lailun Ni’mah
ALCHEMY:Journal of Chemistry Vol 8, No 1 (2020): ALCHEMY: Journal of Chemistry
Publisher : Department of Chemistry, Faculty of Science and Technology UIN Maulana Malik Ibrahim Malan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (590.944 KB) | DOI: 10.18860/al.v8i1.9097

Abstract

Gelatin and chitosan have been widely used in various industries such as pharmaceuticals, textiles, cosmetics, food processings, and others. Gelatin has different mechanical properties compared to chitosan, especially its tensile strength and elongation. In this study, gelatin (Ge) was obtained commercially, while chitosan (Ch) was obtained from the skin of windu shrimp via deproteination, demineralization, and deacetylation of chitin into chitosan. The results of this study indicated that the degree of deacetylation of chitosan was 52.06%. Afterward, various films including Ge, Ch, Ge 4%-Ch 1.5%, Ge 4%-Ch 3%, Ge 4%-Ch 4% were prepared by the casting method. The film of Ge 4%-Ch 4% exhibited the best tensile strength and elongation with values of 0.6 MPa and 21.53%, respectively. Gelatin dan kitosan merupakan biopolimer alam yang selama ini banyak digunakan di berbagai industri seperti farmasi, tekstil, kosmetik, pengolahan pangan dan lain sebagainya. Gelatin memiliki sifat mekanik yang berbeda dibandingkan dengan kitosan terutama kuat tarik dan elongasinya. Pada penelitian ini, gelatin (Ge) diperoleh secara komersial, sedangkan kitosan (Ch) diperoleh dari kulit udang windu melalui proses deproteinasi, demineralisasi, dan deasetilasi kitin menjadi kitosan. Hasil penelitian ini menunjukkan derajat deasetilasi kitosan sebesar 52,06%.  Selanjutnya, dilakukan proses pembuatan film Ge, Ch, Ge 4%-Ch 1,5%; Ge 4%-Ch 3%, Ge 4%-Ch 4% dengan menggunakan metode casting. Film Ge 4%-Ch 4% memiliki kuat tarik dan elongasi yang paling baik yaitu 0,6 MPa dan 21,53%, berturut-turut.