PENGARUH LAJU ALIR GAS PEMBAWA TERHADAP PEMBUATAN KATALIS HETEROGEN NANOKOMPOSIT ZnO/Fe2O3

<p><strong><em>Abstract</em></strong><strong>: </strong><em>Biodiesel is an alternative fuel. Biodiesel was produced through the transesterification of vegetable oils or animal with the aid of a catalyst. One of them is the ZnO heterogeneous catalyst which have high reaction yield. To increase the yield of the reaction, the size of the catalyst needs to be minimized, but the separation be more difficult. Fe₂O₃ compounds was added to separation due to its magnetic properties. This study was conducted to obtain nano-composite ZnO/ Fe₂O₃ heterogeneous catalysts and determine the effect of carrier gas flow rate on the characteristics of the catalyst particle by pyrolisis flame spray method. Precursor solution of Zn(NO₃)₂ and Fe (NO₃)₃ was nebulized on Nebulizer OMRON NEU-17 and flows to the burner tube with the different carrier gas flow rate. At the same time, LPG gas burners and combustion air was passed through the inner and outer annular burner. The solid combustion products was inhaled by exchauster and filtered by using a particle filter. The solid particles obtained was analyzed by XRD, SEM, and BET. The results of XRD analysis showed that the smaller the carrier gas flow rate the greater intensity of radiation so that it gained the better crystallinity. The results of SEM and BET analysis showed that the mostly of the particles were nano-sized. So the smaller the carrier gas flow rate, the smaller diameter is formed and the larger the specific surface area.</em><em></em></p>

PEMBUATAN BIOFLOKULAN DARI PATI TALAS (COLOCASIA ESCULENTA L. SCHOOTT) DAN POLYACRILAMIDE DENGAN METODE PENCANGKOKAN (GRAFTING)

<p>Abstract: Clean water is the basic needs. One of the way to get clean water is using<br />flocculation process. The flocculant copolymer is the combination of natural polymers and<br />synthetic polymers that is more effective than the straight-chain polymer flocculants. Starchgraft-polyacrylamide</p><p>(St-g-PAM) is the copolymer flocculant. This flocculant is synthesized by<br />the grafting to separate into two phases. The first stage is the synthesis of non-terminated<br />polyacrylamide (nt-PAM) and then the grafting of the non-terminated polyacrylamide (nt-PAM)on taro starch polymer backbone. This study aims to determine the effect of initiator<br />concentration ratio, the concentration of the terminator, and the termination time of %GE, %GY,<br />intrinsic viscosity and molecular weight. Polymerization was carried out in a glass reactor<br />equipped with a stirrer and isothermal conditions. The resulting products were analyzed by FTIR.</p><p>The analysis shows the existence bonds of starch and acrylamide, the presence of these<br />groups proves that St-g-PAM was formed. The increase in the initiator concentration leads to an<br />increase % GY, intrinsic viscosity and molecular weight but subsequently decreased. The<br />increase in the concentration of terminator and the length time of termination cause % GY,<br />intrinsic viscosity and molecular weight decreased. In this study, the concentration of acrylamide<br />is smaller than the concentration of starch, it makes not all of the starch backbone can join the<br />acrylamide chain so %GE can not be calculated. Thus it can not explain the effect of the initiator<br />concentration, the concentration of the terminator, and the termination time of %GE<br />Keywords: Starch-graft-Polyacrylamide, grafting to, bioflocculant</p>

PROFIL FERMENTASI PADA PRODUKSI MINYAK MIKROALGA MENGGUNAKAN Nannochloropsis oculata DALAM MEDIUM BG-11

<p>Abstract: The Government has launched a substitution program of petroleum based oil with<br />renewable energy sources. One of the programs implemented is substitution of diesel oil by<br />biodiesel. However, there is a problem with biodiesel raw material resources, i.e. alternative of<br />crude palm oil avoiding competition of food utilization. The prospective one is microalgae oil.<br />The objective of this study is to explore fermentation profile of Nannochloropsis oculata growing<br />in medium BG-11. Experiments used a bioreactor equipped with a gas absorber and N. oculata<br />cultured in medium BG-11. While culturing N. oculata, oxygen was supported in the gas<br />absorber by circulating the medium through bioreactor – absorber – bioreactor. Sampling was<br />carried out periodically once a day (24 hours) and analysis of samples included cell<br />temperature, salinity, pH, cell dry weight, and oil content. The data were presented in a<br />graphical form of the parameter profile.<br />Keywords: microalgae, fermentation profile, Nannochloropsis oculata., oil content</p>

KINERJA PEMBANGKIT LISTRIK DUAL-FUEL KAPASITAS 5 kW BERBASIS GASIFIKASI SEKAM PADI BERUNGGUN TETAP

<p>Abstract: Producer gas from rice husk gasification is the potential gaseous fuel for partially<br />substituting diesel fuel demand as it contains combustible gases (CO, H<br />2<br />). This<br />research examined the effects of air flow rate entering the diesel engine and electrical load on<br />diesel fuel consumption, electrical power of generator, and rice husk specific consumption in<br />gasifier. Gasification process took place in a downdraft air-blown gasifier with 10 cm throat<br />diameter. At rice husk consumption rate of 1 kg/hour and temperature of 827<br />C, the Specific<br />Gasification Rate (SGR) was 81.53 kg/(m<br />.hour) and the solid residue was 36% (w/w) of input<br />biomass. Total combustible gas content in producer gas was 21.6%. It was observed that diesel<br />fuel saving of 9.32% was obtained at air flow rate of 1.55 × 10<br />2<br />-3<br />m<br />/s and electrical load of 95%<br />from maximum generator power. Using producer gas at flow rate of 0.91 × 10<br />3<br />/s caused<br />generator de-rating of 8.33% at electrical load of 10%. Generating 1 kWh of electricity at air flow<br />rate of 2.99 × 10<br />-3<br />m<br />/s and electrical load of 95% required 1.85 kg of rice husk. A kilogram of<br />rice husk may substitute 0.26 L of diesel fuel at this air flow rate and load.<br />3<br />Keywords: rice husk; gasification; dual-fuel; specific consumption; de-rating<br />, and CH<br />4<br />o<br />-3<br />m<br />3</p>

PENGARUH JENIS PELARUT TERHADAP RENDEMEN MINYAK SEREH WANGI (CYMBOPOGON WINTERIANUS)

<p>Abstract: In Indonesia the lemongrass plant is the herbaceous plant species called<br />Cymbopogon winterianus. This plant is often used for flavoring food kitchen, disinfectant,<br />mosquito repellent and can be used as a perfume (essential oils). The essential oil has physical<br />characteristics, such as color, taste, odor and specific gravity. The aim of this study was to<br />determine yield of the essential oil of lemongrass plant by extraction method with variations of<br />solvent ratio (n-hexane, ethanol, and acetone). Initially the lemongrass was dried for a few<br />minutes. The lemongrass dried was reduced about 1/2 cm. The lemongrass 250 grams was<br />wrapped with filter paper and extracted for 12 hours with the ratio 1:2 (sample:solvent) using<br />different types of solvents (n-hexane, ethanol, and acetone) at the boiling point of each solvent.<br />For the purification process, separating the solvent from essential oils used simple distillation.<br />From the results of the study was concluded that the alcohol produces greater yields of<br />essential oil (31.96 %) in the liquid phase than the acetone (46.24 %) in the liquid phase and n hexane<br />(1.3<br />%)<br />in<br />the<br />solid<br />phase.<br />Keywords: lemongrass, aromatic lemongrass oil, extraction, sokletasi, yield</p>

PENYERAPAN GAS KARBONDIOKSIDA (CO 2 ) DALAM BIOGAS DENGAN LARUTAN Ca(OH)2

<p>Abstract: Carbon dioxide content in biogas produced by fermentation is still high. Because of<br />that, biogas need a process purification to reduce carbon dioxide content. In this work, Ca(OH)2<br />solution was contacted with biogas in a column for reducing the CO<br />2<br />content. This research<br />studied the effect of packing type used in absorber column on the rate of CO<br />2<br />reduction. Based<br />on experimental data and modelling, it was found that the reaction between CO<br />2<br />followed first order reaction. The constant of rate reaction was affected by the packing type<br />which using glass ball, plastic pipe, ceramic, wood, and clay roof, the constant rate were 0.781,<br />0.464, 0.916, 0.637, and 0.987 min<br />Keywords: Biogas, CO<br />2<br />, Ca(OH)2<br />-1<br />, respectively.<br />, absorber, rate of reaction</p>

ZAT WARNA DARI GETAH TANGKAI DAUN PISANG (MUSA SSP.)

<p>Abstract: One of the natural dye sources for the brown color called tannins is Resin Banana<br />Leaf Stem. Tannins were obtained through the extraction process of Resin Banana Leaf Stem<br />using 96% ethanol. This study aimed to obtain a total level by extraction and drying. The<br />influence of the material with a solvent ratio (weight/volume), time, temperature, and rotational<br />speed stirrer in the extraction of dye from resin stem of banana were studied to get an optimum<br />process. This experiment is using some ratios of the weight of banana leaf to the volume of<br />solvent, i.e.: 20:200 and 50:200 (g/ml). The condition was set at 63<br />C for 160 minutes and<br />stirring rotational speed of 200 rpm. With the same material, extraction with soxhlet was done<br />until the solvent becomes clear. Total tannin was obtained at 7.68%. With a three-neck flask<br />extraction process obtained the optimum conditions, i.e.: the ratio of the weight to the volume of<br />solvent of 50:200 g/ml at 63<br />o<br />o<br />C, and stirring rotational speed of 200 rpm for 140 minutes. This<br />condition process produce heavy tannins about 29.2576 mg.<br />Keywords: banana stem, resin, extraction, natural dye</p>

PRODUKSI BIOETANOL DARI SORGUM (SORGHUM BICOLOR)SECARA KONTINYU DARI REAKTOR UNGGUN TERFLUIDISASI (FLUIDIZED BED BIOREACTOR)

<p>Abstract: Many studies have been done regarding the optimization of fermentation process to<br />produce bioethanol. This study aims to determine the effect of feed flow rate during the<br />fermentation. Fermentation is performed continuously by the method of Simultaneous<br />Saccharification Fermentation (SSF)using column Fluidized bed (fluidized bed bioreactor). The<br />used materials are sorghum which converted into glucose in the process of liquefaction and<br />saccharification. This study used the variation of the feed flow rate of 240, 260, 280, and 300<br />ml/minute with a substrate concentration of 25% (m/v). Fifteen minutes before the fermentation<br />was complete, for each flow rate was sampling every 5 minutes to calculate the levels of<br />glucose, total glucose levels, and levels of bioethanol. The results showed that the feed flow<br />rate of 240,260,280 and 300 ml/minutes produced bioethanol with the each highest levels of<br />8.32, 8.32, 8.33, 8.33g/L/h, respectively.<br />Keywords: flow rate, amobil, fluidized bed bioreactor</p>

FRAKSINASI KOMPLEKSASI UREA PADA MINYAK DEDAK PADI DALAM PENINGKATAN KONSENTRASI ASAM LEMAK TAK JENUH

<p>Abstract: Polyunsaturated fatty acid in rice bran oil is good for health and valuable. The aims of<br />this research were identifying influence of complexation temperature and time on the<br />enhancement of polyunsaturated fatty acid consentration. This research began with<br />saponification and extraction of rice bran oil as pretreatment process. Then, complexation<br />process was done with urea-ethanol solution ration of 35:175 (w/v). Complexation was carried<br />out by mixing 10 gram of free fatty acid of rice bran oil with 40 ml of urea-ethanol solution and<br />then followed by separation process and iod number analysis. The result of temperature<br />variation showed that the iod number of sample 0 hour, 2 hours, 12 hours, and 24 hours were<br />29.18; 32.99; 36.04; and 37.82. Then the iod number of sample with variable temperature 28<br />o<br />C, 5<br />o<br />C, -2<br />o<br />C and -7<br />C were 37.82; 39.85; 43.15; and 44.16. The longer time and the lower<br />temperature of complexation increased polyunsaturated fatty acid consentration indicated by iod<br />number rising.<br />o<br />Keywords: Rice bran oil, Polyunsaturated Fatty Acid, fractionation urea complexation, iod<br />number bixa</p>

PENGARUH LAJU ALIR GAS PEMBAWA TERHADAP PEMBUATAN KATALIS HETEROGEN NANOKOMPOSIT ZnO/Fe 2 O 3

<strong><strong></strong></strong><p>Abstract: Biodiesel is an alternative fuel. Biodiesel was produced through the transesterification<br />of vegetable oils or animal with the aid of a catalyst. One of them is the ZnO heterogeneous<br />catalyst which have high reaction yield. To increase the yield of the reaction, the size of the<br />catalyst needs to be minimized, but the separation be more difficult. Fe<br />2<br />O<br />3<br />compounds was<br />added to separation due to its magnetic properties. This study was conducted to obtain nanocomposite<br />ZnO/<br />Fe<br />2<br />O<br />3<br />heterogeneous catalysts and determine the effect of carrier gas flow rate<br />on the characteristics of the catalyst particle by pyrolisis flame spray method. Precursor solution<br />of Zn(NO<br />3<br />)2<br />and Fe (NO<br />3<br />)3<br />was nebulized on Nebulizer OMRON NEU-17 and flows to the<br />burner tube with the different carrier gas flow rate. At the same time, LPG gas burners and<br />combustion air was passed through the inner and outer annular burner. The solid combustion<br />products was inhaled by exchauster and filtered by using a particle filter. The solid particles<br />obtained was analyzed by XRD, SEM, and BET. The results of XRD analysis showed that the<br />smaller the carrier gas flow rate the greater intensity of radiation so that it gained the better<br />crystallinity. The results of SEM and BET analysis showed that the mostly of the particles were<br />nano-sized. So the smaller the carrier gas flow rate, the smaller diameter is formed and the<br />larger the specific surface area.<br />Keywords: nanocomposite, carrier gas, flame spray pyrolysis</p>