Surface Properties and Adsorption Capacities of Rice Bran-Activated Carbon

The growing need for activated carbon requires alternative raw materials to replace non-renewable raw materials whose existence is decreasing. Biomass is a very promising precursor, one of which is from rice bran. This research concerns the development of activated carbon derived from rice bran. Carbonization was carried out at 600 OC and physically activated with nitrogen flow rates of 150 mL/min for 40, 80, and 120 minutes. The activated carbons produced (AC-D40, AC-D80, and AC-D120) were characterized to determine the surface properties, surface morphology, and adsorption capacity for nitrogen and blue methylene adsorptions. The results showed that activated carbon that activated for 80 minutes (AC-D80) had the best characteristics. With a pore surface area of 109.389 m2/g, a pore volume of 0.083 cm3/g, and pores that mostly distributed in the micropore area, this activated carbon has the highest adsorption for nitrogen (53.874 cm3/g) and methylene blue (87.560 mg/g) adsorptions compared to activated carbon with activation times of 40 minutes (AC-D40) and 120 minutes (AC-D120)

Characteristics and performance analysis of different grain sizes bamboo-activated carbons for motorcycle flue gas adsorption

The use of fossil fuels in human activities such as motorcycles has led to an increase in the concentration emitted in the atmosphere. Various efforts and methods such as adsorption using activated carbon have been developed and applied to reduce the emission. Therefore, this study focuses on the characteristics and performance of bamboo-activated carbons in the adsorption of motorcycle flue gases. This was carried out using different grain sizes (z) of activated carbons AC-M1, AC-M2, and AC-M3 for grain sizes of z≤250, 250<z≤420, and 420<z≤590 microns, respectively, which were derived from swat bamboo and carbonized at a temperature of 750 ○C. Furthermore, physical activation was applied by heating the charcoal at the same temperature under a nitrogen flow rate of 150 mL/min nitrogen. The Thermogravimetric (TGA), scanning electron microscopy (SEM), and adsorption isotherm tests were employed for the characterization of activated carbons. Additionally, the performances of activated carbons for motorcycle flue gas adsorption (CO2, CO, and HC) were carried out by a motorcycle emission test. According to the results, activated carbon AC-M1 produced the best characteristics and performance for adsorption of motorcycle flue gas, as it has a pore volume of 0.135 cm3/g, a specific surface area of 244.69 m2/g, and a nitrogen adsorption capacity of 87.047 cm3/g. These characteristics prove to have good adsorption efficiencies at 100 %, 87.30 %, and 100 % for adsorption of CO2, CO, and HC, respectively

Characteristics and performance analysis of activated carbons derived from different precursors and activators for waste water adsorption

Domestic waste such as methylene blue from the dyeing process and detergent from laundry activities are sources of water pollution. Before being dumped into the water, this waste must be minimized. One approach that can be utilized is the adsorption method with activated carbon. To generate activated carbon with the properties required for this purpose, an appropriate precursor and manufacturing conditions must be chosen. The objective of this research is to investigate the characteristics and performance of activated carbon derived from various precursors (Petung and Santong bamboos) and activators (Ar, N2, and CO2) for detergent and methylene blue dye adsorption. The difficulty to be solved is determining the best precursor and activator for maximum methyl blue and detergent adsorption. Characterizations included FTIR, XRD, SEM, TGA, and adsorption isotherm testing. The study's findings show that activated carbons have functional groups O-H (hydroxyl), C-H (aldehydes and alkenes), C=C aromatic rings, C-H aromatic groups, and an amorphous structure. The presence of a porous and amorphous structure, as well as the C=C aromatic ring, makes activated carbons capable of absorbing methyl blue and detergent. Santong bamboo-activated carbon activated with argon has the best characteristics and adsorption capability. This activated carbon has a fixed carbon content of 76.34 %, pore volumes of 0.362 cc/g, average pore widths of 1.967 nm, pore surface area of 291.487 m2/g, bimodal pore size distribution, and methylene blue and detergent adsorption capabilities of 19.733 cc/g and 1.689 cc/g, respectively. The results obtained are on a laboratory scale, which necessitates additional research, particularly on how to create reservoirs and regenerate activated carbon simply and affordabl

Development of mesoporous activated carbons derived from brewed coffee waste for CO2 adsorption

The primary cause of rising CO2 concentrations in the atmosphere is the use of fossil fuels in motor vehicles and factory activities in industry. CO2 levels in the atmosphere can be controlled and reduced by using low-carbon energy and capturing and storing CO2. One widely used way for CO2 capture and storage is adsorption method. This method necessitates the use of an adsorbent, one of which is activated carbon. In this study, brewed coffee waste was converted into activated carbons, characterized, and tested for carbon dioxide adsorption. Brewed coffee waste was dehydrated at 105 ºC for an hour before being carbonized at 550 °C and activated at 670, 700, and 730 °C, with a 200-ml/min nitrogen injection during activation. Activated carbons with activation temperatures of 670, 700, and 730 °C were denoted as AC-670, AC-700, and AC-730, respectively. A series of TGA, SEM, and adsorption isotherm tests were used to determine the proximate components, surface morphology, and surface structure of the activated carbons produced. To assess the adsorption capacities of activated carbon on CO2, the gravimetric CO2 adsorption isotherm method was used. According to the findings of the study, increasing activation temperatures cause variable properties in activated carbon. When using an activation temperature of 700 °C, the most appropriate properties of activated carbon can be obtained. It has 425.843 m2/g specific surface area, 0.345 cm3/g pore volume, 3.423 nm pore diameter, 235.628 cm3/g nitrogen adsorption capacity, and 4.183 mmol/g CO2 adsorption performance. This study provided a simple way converting brewed coffee waste into activated carbon with excellent performance for CO2 adsorptio

Potency of Micro Hydro Power Plant Development Use of Kelampuak River Flow Located in Tamblang Village – Buleleng

Need of electrical energy is increasing along with people population and economic growth. According to PLN data, Bali Province’s electrical consumption is predicted growth 5,6% in average every year. Until year 2007, electrical condition in Bali is categorized critical. If Power Plat in Bali, PLTG Gilimanuk that has power 130 MW is out of system, affecting Bali’s electrical back up is minus. Consecuenlly, it will be extinguishing if there is not adding power plan or new energy supply. This problem needs to be anticipated by use of thermal energy program such as coal, gas and geothermal and use of alternative energy such as solar, wind and ocean energies. Regency of Buleleng is one of Regency in Bali having potency of renewable energy development especially water resource. It has some rivers that have potency to be developed as a Micro Hydro Power Plant (PLTMH). One of them is Kelampuak River which is located in Tamblang Village. As a first step in developing of Micro Hydro Power Plant, it needs to be known water debit and head of the river. For that reason, it needs to be investigated debit and head of Kelampuak River so that it can be predicted the power can be generated

Pack Carburizing Baja Karbon Rendah

Abstrak: Penelitian ini bertujuan untuk mengetahui sifat mekanis khususnya kekerasan dan kekuatan tarik baja karbon rendah setelah dikarburasi menggunakan media karburasi (carburizer) campuran 80% arang bambu dan 20% BaCO3 sebagai energizer. Penelitian dilakukan dengan memasukkan specimen uji ke dalam kotak pack carburizing yang telah berisi media karburasi, kemudian kotak pack carburizing dimasukkan ke dalam dapur pemanas dan dipanaskan sampai suhu 9500C. Pada suhu tersebut specimen ditahan selama 4 jam kemudian kotak baja dikeluarkan dari dapur pemanas. Specimen dikeluarkan dari kotak baja dan didinginkan di udara. Selanjutnya dilakukan pengujian kekerasan menggunakan Vikers Testing Machine. Sedangkan uji tarik dilakukan dengan menggunakan Universal Testing Machine. Hasil penelitian menunjukkan bahwa setelah dikarburizing baja karbon rendah mengalami perubahan sifat mekanis. Kekerasan raw material sebesar 183,60 HV1 meningkat 100,68 % menjadi 368,46 HV1 setelah dikarburizing. Demikian juga kekuatan luluh dan kekuatan tarik yang semula 31,99 kg/mm2 dan 42,08 HV1 kg/mm2 meningkat secara berturut turut menjadi 48,94 kg/mm2 dan 55,05 kg/mm2. Namun di sisi lain, terjadi penurunan elongasi yang semula 30,07 % menurun menjadi 7,6%. Kata kunci: Pack carburizing, kekerasan, kekuatan tarik, media karburasi Abstract: This research is focused on the mechanical properties, especially on the hardness and tensile strength of low carbon steel after pack carburizing process by use of carburizer consisting of 80% bamboo coal and 20% BaCO3 as energizer. The research was carried out by packing of low carbon steel specimens in a steel box filled of carburizer. The steel box was then loaded into electric furnace, heated up to 9500C, and socked at the temperature during 4 hours. After that socking time, the steel box was drooped out from electric furnace and specimens were taken from steel box and colded in the air. Furthermore, it was undertaken hardness and tensile test by use of Vickers Hardness Tester and Universal Testing machine respectively. The result of research showed that there were mechanical properties changes of low carbon steel after carburizing process. Hardness of raw material (183.60 HV1) increased about 100.68% to 368.46 HV1 after carburizing. Furthermore, yield strength of 31.99 kg/mm2 and tensile strength of 42.08 kg/mm2 also increased to 48.94 kg/mm2 and 55.05 kg/mm2 respectively. However, there was a decrease in elongation from 30.07% to 7.6%. Keywords: Pack carburizing, hardness, tensile strength, carburize

Distribusi Kekerasan dan Total Case Depth Baja Karbon Rendah Setelah Proses Pack Carburizing

Penelitian ini bertujuan untuk mengetahui distribusi kekerasan dan menentukan total casedepth baja karbon rendah setelah proses pack carburizing dengan variasi temperaturpemanasan. Penelitian dilakukan dengan menggunakan media karburasi 80% arang tulangkambing dan 20% enrgizer CaCO3. Variasi temperatur pemanasan yang digunakan adalah8500C, 9000C dan 9500C, diholding selama 4 jam dan didinginkan dengan air. Total case depthdiperoleh dengan menentukan kedalaman dimana kekerasan bahan tanpa perlakuan samadengan kekerasan bahan setelah proses pack carburizing. Hasil penelitian menunjukkan bahwasemakin tinggi temperatur pemanasan semakin tinggi distribusi kekerasan. Sampai kedalaman2,5 mm, semakin jauh dari permukaan semakin rendah kekerasan yang dicapai. Total casedepth didapat sampai kedalaman 2,5 mm, setelah itu kekerasan relatif sama antara materialtanpa dan dengan perlakuan. Kekerasan tertinggi diperoleh sebesar 241,629 VHN pada jarak0,5 mm dari permukaan dengan temperatur pemanasan 9500C.Kata Kunci: Total case depth, pack carburizing, energizer, kekerasan This study aims to determine the hardness distribution and total case depth of low carbon steelafter pack carburizing process with heating temperature variation. The study was conducted byusing a carburizing medium 80% goat bones charcoal and 20% energizer CaCO3. Heatingtemperature variations were carried out at 8500C, 9000C and 9500C, holding during 4 hours andcooled with water. The total case depth was obtained by determining the depth where thehardness of the untreated and treated materials was the same relatively. The results showed thatthe higher heating temperature the higher hardness distribution. The deeper of distance thelower hardness obtained until 2,5 mm depth. The total case depth was obtained until 2.5 mm.After this distance the hardness between untreated and treated materials was the same. Thehighest hardness reached 241.629 VHN at a distance of 0.5 mm from the surface with heatingtemperature 9500C.Keywords: Total case depth, pack carburizing, energizer, hardnes

Simulasi dan Studi Eksperimen Defleksi Beam Bright Mild Steel Akibat Variasi Beban Horisontal

Beam is a structural member whose cross-sectional dimensions are relatively smaller than its length. Beams play significantroles in many engineering applications, including buildings, bridges, automobiles, and airplane structures. Beams arecommonly subjected to transverse loading, which is a type of loading that creates bending in the beam. In designing of amachine component or structure, deflection has an important role to be considered. If deflection occurred exceeds limitallowed, it can affect serious hazard on machine elements or structure due to it can affect of component deviate from its mainfunction. In this research, material to be used was Bright Mild Steel (ASTM 1060), with specimen in the form of portal beam.Physical condition of beam was modeled use of BEAM3 2D. Variation of loads to be applied were W = 100, 150, 200, 250,300, 350, 400, 450, 500, and 550 gr and concentrated in the one of portal in vehorizontal direction. The result of simulationwas verificated by experimental data. Evaluation was carried out by statistical test (t-test). The result of simulation iscategorized to be good if the result of simulation is same with experimental data. The result of research shows thatloading has a significant effect on the deflection. The higher load affect the higher of deflection Modeling use of BEAM3 2Dgave good result of deflection. This is showed from t-test have done, where the result of simulation was same withexperimental data

Simulation, Experimental and Analitical Study of Deflection at End Curved Beam Affected by Single Concentrated Load

Deflection has an important role in order to design structure or machine component, beside consideration of stresscalculation. This is due to although stress is still smaller then stress allowed by material strength, but probably happen thatdeflection exceeds limit allowed. That condition affects serious hazard on machine elements or structure due to it can affectof component deviate from its main function. One of element which is often experience of deflection is beam. Beams playsignificant roles in many engineering applications, including buildings, bridges, automobiles, and airplane structures. In thisresearch, material to be used was Steel ASTM 1060, with specimen in the form of curved beam. Physical condition of beamwas modeled use of BEAM3 2D. Variation of loads to be applied were W = 100, 150, 200, 250, 300, 350, 400, 450, 500, and550 gr in vertical direction. The result of simulation was verificated by analytical and experimental data. Evaluation wascarried out by statistical test (t-test). The result of simulation is categorized to be good if the result of simulation is samewith analytical and experimental data. The result of research shows that loading has a significant effect on the deflection.The higher load affect the higher of deflection Modeling use of BEAM3 2D gave good result of deflection. This is showedfrom t-test have done, where the result of simulation was same with analytical and experimental data. Other advantage ofsimulation was deflection result obtained was not limited only at the end of beam, but it can predict of deflection at eachnode or point desire