Jurnal Rekayasa Kimia & Lingkungan
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Synthesis of Heterogeneous Catalysts NaOH/CaO/C From Eggshells for Biodiesel Production Using Off-Grade Palm Oil
Full text linkA heterogeneous catalyst, such as Calcium Oxide (CaO), is widely used in biodiesel production due to its various advantages over homogeneous ones. The optimum condition for synthesizing this catalyst is determined by calcination temperature and mass ratio. As a result, a modification is required to increase its performance in improving the biodiesel yield. In this study, eggshell waste was modified by calcination, hydration, and dehydration methods integrated with activated carbon and NaOH. It is used as a heterogeneous base catalyst for off-grade palm oil transesterification reactions. The results shows the catalyst with the highest activity is obtained at calcination temperature of 800c and mass ratio of 7 to 3. This is achieved with transesterification reaction conditions, which include a mole ratio of methanol/oil 6 to 1, catalyst concentration of 6%-b oil, and temperature 70c for 3 hours, yielding 79.08% of the biodiesel. Additionally, CaO, Na2CO3, and Ca (OH) 2 materials were found in the catalyst with a catalyst alkalinity value of H greater than 9.3 through X-ray diffraction (XRD) analysis. Several methyl esters, such as palmitate and oleate were also found in biodiesel through Gas Chromatography-Mass Spectrometry (GC-MS) analysis
Effect of Activator Type on Activated Carbon Characters from Teak Wood and The Bleaching Test for Waste Cooking Oil
Full text linkThe starting material for activated carbon was biomass from teak woodcutting, which consists of 47.5% cellulose, 14.4% hemicellulose, and 29.9% lignin. The surface area and iodine number of activated carbons are the factors determining the adsorption ability. This study aims to determine the effect of the activator type on activated carbon characters and test the absorption ability for waste cooking oil. The synthesis stages include carbonization, chemical activation, and then physics activation. The activation process consists of two steps. Firstly, the chemical activation via adding H2SO4, and H3PO4 at room temperature for 24 hours, the second, physical activation by heating at various temperatures of 300, 400, and 500 C for two hours. The characterizations of activated carbon include water content, ash content, iodine number, functional groups, and surface area. Furthermore, the activated carbon was used as an adsorbent for waste cooking oil for 60 minutes at 100 C with a stirring of 500 rpm. The results were analyzed using UV-Vis spectrophotometry at a maximum wavelength of 403 nm. The iodine numbers of activated carbon ranged 481.1-1211.4 mg/g and 494.8-1204 mg/g for H3PO4 and H2SO4, respectively.Activated carbon with H3PO4 of 15% and an activation temperature of 400 C has the highest surface area of 445.30 m2/g. The H2SO4 dan H3PO4 activators can be used to improve the quality of activated carbon in absorbing dyes in waste cooking oil, where the optimum concentration is 10-15% (v/v). The H3PO4 activator tends to produce a higher bleaching percentage than H2SO4
The Application of Nanofiltration Membrane for Palm Oil Mill Effluent Treatment by Adding Polyaluminium Chloride (PAC) as Coagulant
Full text linkThe rapid development of Crude Palm Oil (CPO) production has led to an increase in the production of Palm Oil Mill Effluent (POME) as well. POME will cause problems in the environment because contains high contaminants. This study aims to investigate the effect of the coagulant Polyaluminium Chloride (PAC) variations and the membranes operating pressure on the POME treatment process using the nanofiltration membrane (NF) with the coagulation-flocculation process as pre-treatment. The PAC was used in the coagulation-flocculation process with variations in concentration (5.0; 5.5; 6.0; 6.5; 7.0 g/L). The process was completed by a rapid stirring of 200 rpm for 5 minutes, followed with slow stirring at 60 rpm for 15 minutes and settling time for 30 minutes. The process of membrane nanofiltration was carried out for 60 minutes with variations in operating pressure (8.0; 9.0; and 10 bars). In each treatment process, effluent quality testing was carried out with Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS) and oil/fat as parameters. In addition, an analysis of permeate fluxes and rejection of NF membrane was also carried out. The results of the analysis suggested that the best coagulant doses are 6.0 g/L with the reduction percentage of BOD, COD, TSS and oil/fat at 78.85%; 68.57%; 92.77% and 92.31% respectively. The highest percentage of NF membrane rejection was found at a pressure of 10 bar, which is equal to 94.71%; 94.86%; 97.92% and 95% respectively for BOD, COD, TSS and oil/fat with a flux value of 7.16 L/m2.hours
The Performance and Characterization of Biodegradable Plastic from Tapioca Starch: Effect of Modified Chitosan
Full text linkThe performance and characterization of biodegradable plastic from tapioca starch was studied. Modified the chitosan was one of the ingredients for produce the biodegradable plastics. The produced biodegradable polastic were thin sheet plastic, elastic and transparent. The biodegradable plastic performance had tensile strength between 2,26-3.73 Mpa, elongation ranges from 17.24 to 76.76%, and water absorption ranges from 30.81-268.9%. In antioxidant analyze, apples are wrapped in plastic and had significant mechanical properties changes on 8th day.Morphology scanning result showed that in the chitosan-polyNIPAM there were no cavities may caused high hydrophilicity in the biodegradable plastic
Recovery of Ammonium Metavanadate from Spent Catalyst
Full text linkUtilization of spent catalysts serves to meet the needs of vanadium and to overcome the environmental problem since vanadium is categorized as a hazardous, toxic material. Vanadium from the spent catalysts can be recovered in the form of V2O5 or NH4VO3. However, vanadate compounds (NH4VO3) are considered to be more valuable due to their higher price and easier production process, compared with V2O5. This study aims to find adequate operating conditions to obtain high yields and high purity of NH4VO3 crystals. The results showed that the presence of iron compounds in the extract made the crystals contaminated by brownish colour, so it decreased its purity. Therefore, iron compounds need to be separated first with precipitation. Crystals of NH4VO3 with yield of 60% on spent catalysts and purity of 75% were obtained by extraction using solvent Na2CO3 1.887 M for 60 minutes at room temperature with weight ratio of V2O5 in spent catalyst toward solvent volume (Rvp), 0.006 gram V2O5/mL Na2CO3. It was then continued by precipitation of iron compounds at pH of 12 for 2 hours and crystallization of NH4VO3 using NH4Cl 11.215 M for 4 - 5 hours at 60oC
Selective Reduction of High Alumina-Lateritic Nickel Ore (0.5 Ni-44Fe-16Al2O3)
Full text linkIn this present study, the effect of reductant dosage, temperature and holding time on selective reduction process of high alumina-lateritic nickel ore have been investigated clearly. The lateritic nickel ore was reduced with 5 until 15 wt. % anthracite and 10 wt. % sodium sulfate at reduction temperature of 950C, 1050C and 1150C for 60, 90, and 120 minutes. Magnetic separation process was then conducted to separate the concentrate and tailing. The analysis of reduced nickel ore is performed by the Atomic Absorption Spectroscopy, X-Ray Diffraction, and Secondary Electron Microscopy. The optimal process resulted from the reduction of nickel ore with 10 wt. % anthracite at the temperature of 1050C for 120 minutes which resulted in 0.84% nickel in concentrate. The troilite was not found in reduced ore. The iron grade increased along the increased of reduction temperature. The longer of holding time in selective reduction process increased the nickel grade but it decreased the iron grade
Purification of Biodiesel from Waste Cooking Oil Using Bentonite as Dry Washing Agent
Full text linkThe process of biodiesel purification is an important step in getting biodiesel products that meet specifications as a substitute for fossil-based fuels. Dry washing method has been developed to achieve an effective purication strategy in order to produce high-quality biodiesel. Bentonite can be used as dry washing agent because it has a good adsorbing properties as well as a large pore and surface area therefore can attract polar substances such as glycerol and methanol. The purpose of this research is to know the capability of activated bentonite as dry washing agent for purification of biodiesel produced from waste cooking oil. The activation process of bentonite was carried out using sulfuric acid with concentration 1.5 M. Characterization of the bentonite was conducted using X-Ray Diffraction (XRD) for minerals content and BrunauerEmmettTeller (BET) method for surface area. Bentonite was used as dry washing agent for biodiesel purification by varying washing time (10, 20, 30, 40 and 50 minutes) and adsorbent amount (1, 2, 3, 4 and 5%). The experimental results showed that purification of biodiesel by dry washing using activated bentonite resulted in a better yield and quality than wet washing and dry washing using non-activated bentonite, except the acid number. The best operation condition resulted from this research is at 10 minutes washing time and 1% adsorbent with yield of 94.1%; acid number of 0.4208 mg KOH/gram; density of 0.8838 gram/cm3, viscosity of 3.0617 mm2/s and water content of 1.17%
Activation of Cement Clinker as Catalysts for Transesterification Reaction of Palm Oil Off Grade to Biodiesel
Full text linkCalcium oxide (CaO) is a heterogeneous solid base which is generally used as a catalyst in making biodiesel. It is mainly obtained from cement clinker and activated through calcination method. The purpose of this study was to determine the effect of using cement clinker catalyst on the yield of the biodiesel. A batch reactor with a condenser was used in making the biodiesel under favorable conditions such as calcination temperatures of 700 C, 750 C and 800 C, time of 5, 6 and 7 hours, and catalyst concentration of 1%-w, 2%-w, and 3%-w oil. The analysis involved X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET) for catalysts and Gas Chromatography-Mass Spectrometry (GC-MS). The catalyst calcination temperature determined the optimum conditions. From this study, the conditions necessary for transesterification reaction include the mole ratio of methanol/oil of 6 to 1, the temperature of 70 C for 2 hours and 700 C for 5 hours, and catalyst dosage of 2% by weight. Under these conditions, the yield of the biodiesel was 84.26%. Additionally, at the calcination temperature of 800 C for 7 hours and catalyst dosage of 3% by weight, the yield of the biodiesel was 76.84%. CaO, SiO2, 2CaO.SiO2 and 3CaO.SiO2 were found in the catalyst through XRD analysis. The specific surface areas of the catalyst were 25,497 m2/g (700 C/5 hours) and 35,879 m2/g (800 C/7 hours) through BET analysis. According to the GC-MS analysis, the main components of the biodiesel include methyl palmitate, methyl oleate, and methyl stearate
pemanfaatan selulosa dari limbah kulit buah pinang sebagai bahan baku pembuatan bioplastik
No full textBioplastik adalah salah satu jenis plastik yang terbuat dari sumber biomassa terbarukan. Selulosa dari kulit buah pinang berpotensi sebagai bahan baku pembuatan bioplastik dengan menggunakan gliserol sebagai plastizicer. Tujuan penelitian ini untuk membuat film plastik biodegradable, dimana prosedur penelitian adalah isolasi alfa-selulosa dengan metode delignifikasi, pembuatan bioplastik dengan metode solution casting dan karakterisasi bioplastik. Selulosa yang telah diekstraksi dari kulit buah pinang digunakan untuk pembuatan film plastik. Ekstraksi selulosa menggunakan variasi konsentrasi NaOH saat delignifikasi sebesar 15%, 20%, dan 25% dan bleaching dengan NaOCl 3,5%. Sedangkan pembuatan film plastik menggunakan variasi perbandingan gliserol 0,5 gram, 1 gram, dan 1,5 gram. Dimana karakteristik bioplastik terbaik pada penelitian ini diperoleh pada konsentrasi pelarut NaOH 20% dengan penambahan gliserol 1,5 gram di dapat densitas sebesar 0,3 gr/ml, daya serap terhadap air 128,57%, kuat tarik sebesar 14,57 kgf/mm2, dan % elongasi sebesar 5,44
Pelapisan Silika pada Stainless Steel secara Elektroforesis Disertai Anodisasi untuk Perlindungan Korosi
Full text linkPenelitian ini mempelajari pengaruh anodisasi terhadap karakteristik perlindungan korosi lapisan silika pada permukaan stainless steel. Anodisasi dilakukan menggunakan larutan asam oksalat dengan memvariasikan waktu anodisasi dan beda tegangan. Elektroforesis dilakukan menggunakan campuran sol silika, isopropanol dan asam asetat dengan perbandingan mol 0,0028 : 0,5048 : 0,1938 selama 10 menit dengan amplitudo 0,5 V, frekuensi 80 Hz dan duty cycle 60%. Dilakukan uji Particle Size Analyzer (PSA) terhadap sol silika. Diperoleh distribusi ukuran partikel sebesar 3,19 nm dan zeta potensial -31,68 mV. Dilakukan analisa polarisasi linear dan Electrochemical Impedance Spectroscopy (EIS) dengan larutan NaCl 3,5% serta Scanning Electron Microscopy (SEM) terhadap lapisan yang terbentuk pada permukaan stainless steel. Dari hasil analisa diperoleh logam yang telah dianodisasi dan elektroforesis memiliki kemampuan perlindungan korosi lebih baik dibanding logam tanpa perlakuan. Waktu dan beda tegangan saat anodisasi berpengaruh terhadap karakteristik perlindungan korosi lapisan pada logam. Diperoleh waktu anodisasi optimum selama 20 menit dan voltase 10 volt dengan laju korosi sebesar 0,000659 mm/tahun. Untuk uji EIS, nilai admitan dan nilai tahanan pori masing-masing sebesar 1.824,7 ohm dan 0,0010226 Mho. Hasil SEM menunjukkan bahwa setelah dilakukan anodisasi terbentuk lapisan yang berpori yang nantinya menjadi tempat menempelnya silika pada proses elektroforesis