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"Oil palm empty fruit bunch (OPEFB) is one of the waste products of oil palm plantations and has not been optimally used in Riau Province, Sumatera, Indonesia. OPEFB is reduced by incineration, which causes pollution problems. However, the combustion of OPEFB generates ash, which is rich in potassium. Moreover, OPEFB fiber has good strength, low cost, low density, and biodegradability, and it can be used as composite reinforcement. However, the natural fibers in composites have poor compatibility with the matrix and relatively high moisture absorption. Hydrolysis of OPEFB ash creates a base solution that can be utilized in an alkaline treatment process to increase the mechanical properties of natural composites.The aim of this study was to investigate the effect of various extracts of OPEFB ash on the tensile strength, flexural strength, and water absorption of an OPEFB fiber-polypropylene composite. The experimental design used was the Response Surface Method-Central Composite Design (RSM-CCD). The results showed that the tensile strength increased with an increase of fiber length and concentration of the OPEFB ash extract solution, but tensile strength decreased with a longer soaking time. Flexural strength increased with an increase in fiber length but decreased with an increase in the concentration of the OPEFB ash extract solution and longer soaking time. Water absorption increased with lower and higher concentrations of OPEFB ash extract solution and fiber length and with shorter and longer soaking times. The highest tensile strength (20.100 MPa) was achieved at 5%wt alkaline concentration, 36 h soaking time, and 3 cm fiber length. The highest flexural strength (30.216 MPa) was achieved at 5%wt alkaline concentration, 12 h soaking time, and 3 cm fiber length. The lowest water absorption (0.324%) was achieved at 10%wt alkaline concentration, 24 h soaking time, and 2 cm fiber length."

"Oil palm empty fruit bunch (OPEFB) is one of the waste products of oil palm plantations and has not been optimally used in Riau Province, Sumatera, Indonesia. OPEFB is reduced by incineration, which causes pollution problems. However, the combustion of OPEFB generates ash, which is rich in potassium. Moreover, OPEFB fiber has good strength, low cost, low density, and biodegradability, and it can be used as composite reinforcement. However, the natural fibers in composites have poor compatibility with the matrix and relatively high moisture absorption. Hydrolysis of OPEFB ash creates a base solution that can be utilized in an alkaline treatment process to increase the mechanical properties of natural composites. The aim of this study was to investigate the effect of various extracts of OPEFB ash on the tensile strength, flexural strength, and water absorption of an OPEFB fiber-polypropylene composite. The experimental design used was the Response Surface Method-Central Composite Design (RSM-CCD). The results showed that the tensile strength increased with an increase of fiber length and concentration of the OPEFB ash extract solution, but tensile strength decreased with a longer soaking time. Flexural strength increased with an increase in fiber length but decreased with an increase in the concentration of the OPEFB ash extract solution and longer soaking time. Water absorption increased with lower and higher concentrations of OPEFB ash extract solution and fiber length and with shorter and longer soaking times. The highest tensile strength (20.100 MPa) was achieved at 5%wt alkaline concentration, 36 h soaking time, and 3 cm fiber length. The highest flexural strength (30.216 MPa) was achieved at 5%wt alkaline concentration, 12 h soaking time, and 3 cm fiber length. The lowest water absorption (0.324%) was achieved at 10%wt alkaline concentration, 24 h soaking time, and 2 cm fiber length."

"The combination ofbaffled air flotation and a membrane system for the treatment of palm oil milleffluent (POME) was studied. The POME was obtained from a palm oil factory inPTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions,such as the hydraulic retention time and air flow rates, were varied to findthe optimum process. The air flotation process is able to reduce theconcentration of suspended solids and fats/ oils contained in the wastewater,which increases the performance of the membrane by reducing clogging. Theresults showed that this method was promising for POME treatment. The optimumorganic removal efficiency of the air flotation pretreatment was obtained atHRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequentlypassed through an anaerobic membrane system to achieve the highest removalefficiency treatment. The removal efficiency of chemical oxygen demand (COD),total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS),mixed liquor volatile suspended solids (MLVSS), and fats/oils after passingthrough the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%,respectively. The results also showed that the pH could be neutralized to 6.18,while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A highquality of effluent was obtained, which met the standards for POME effluent."

"This study was aimed todetermine the reaction stoichiometry between Cu(II) and di-2-ethylhexylphosphoricacid (D2EHPA) in Waste Palm CookingOil (WPCO). The stoichiometry was computed based onthe followingexperimentalmethods, namely slope analysis, loading test and Job?smethod. Slope analysis was used to measure the variation of the distribution coefficient"

"The research aims to scale up a small-scale stirred batch reactor to a large-scale stirred batch reactor in order to degum crude palm oil for use as a raw material in biodiesel production. The scale-up is based on the similarity of fluid Reynolds numbers in the two differently sized reactors. To achieve this aim, computational fluid dynamic modeling and simulations of the two reactors were performed. A small-scale palm oil degumming process was carried out in a 250 cc autoclave reactor using a magnetic stirrer at 500 rpm. The simulation results of this small reactor yielded a fluid Reynolds number in the range of 5 to 3,482. The large-scale reactor proposed in this research is 1.25 m3 in volume and is equipped with two impellers: a pitched blade impeller and a Rushton turbine impeller. The pitched blade impeller is placed over the Rushton turbine impeller. They are rotated at 100 rpm. Under this setting and operation, the resulting fluid Reynolds number was in the range of 486 to 202,000. This result indicates that the large-scale reactor was able to reproduce the reaction performance obtained in the small-scale reactor."

"The definition of the physical and mechanicalproperties of sugarcane trash pellets were necessary for the designconsiderations relating to storage, handling andprocessing equipment. The mixing ratios of groundsugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulkdensity, true density, porosity, durability and compressive strength. The results show that the mixing ratio byweight of 1.0:0.25:0.85 and pelleting speed of 120to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strengthof biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"The presentstudy investigated the mechanical properties and microstructure of ultrafinegrained (UFG) brass processed by four passes of equal channel angular pressing(ECAP) and annealed at elevated temperatures. The mechanical properties of allsamples were assessed using tensile and micro-hardness tests. Microstructureanalysis was performed using optical microscopy (OM) and scanning electronmicroscopy (SEM). Ultimate tensile strengths (UTS) and yield strengths (YS) of878 and 804 MPa, respectively, ductility of 15%, and hardness of 248 HV wereobtained for samples processed by four passes of ECAP with equivalent truestrain of 4.20. Annealing at 300°C caused UTS and YS to decrease significantly,to 510 and 408 MPa, respectively, ductility to increase to 28%, and hardness todecrease to 165 HV. Fractography analysis of un-annealed samples after fourECAP passes showed small brittle fractures with shallow dimpling. Ductilefailures were found on annealed samples. After four ECAP passes, themicrostructure of un-annealed samples was UFG and dominated by lamellar grainwith shear band. In contrast, after annealing, the microstructure changed dueto recrystallization, showing nucleation and grain growth."

"This paper reports onthe investigation of thermal properties of Kapok, Coconut fibre and Sugarcanebagasse composite materials using molasses as a binder. The composite materials were moulded into12 cylindrical samples using Kapok, Bagasse, Coconut fibre, Kapok and Bagassein the ratios of (70:30; 50:50 and 30:70), Kapok and Coconut fibre in theratios of (70:30; 50:50 and 30:70), as well as a combination of Kapok, Bagasseand Coconut fibre in ratios of (50:10:40; 50:40:10 and 50:30:20). The sample size is a 60 mmdiameter with 10?22 mm thickness compressed at a constant load of 180 N using a Budenbergcompression machine. Thermal conductivity and diffusivity tests were carriedout using thermocouples and theresults were read out on a Digital Multimeter MY64 (Model:MBEB094816), whilea Digital fluke K/J thermocouple meter PRD-011 (S/NO 6835050) was used to obtain thetemperature measurement for diffusivity. It was observed that of all the twelvesamples moulded, Bagasse, Kapok plus Bagasse (50:50), Kapok plus Coconut fibre(50:50) and Kapok plus Bagasse plus Coconut fibre (50:40:10) has the lowestthermal conductivity of 0.0074, 0.0106, 0.0132, and 0.0127 W/(m-K) respectivelyand the highestthermal resistivity. In this regard, Bagasse has the lowest thermalconductivity followed by Kapok plus Bagasse (50:50), Kapok plus Bagasse plusCoconut fibre (50:40:10) and Kapok plus Coconut fibre (50:50)."

"The main problem with the slurry process is the difficulty in recovering the photocatalyst nanoparticle from water following purification. An alternative solution proposed the photocatalyst be immobilized on magnetic carriers, which would allow them to be recollected from the water suspension following treatment using an external magnetic field. Magnetically photocatalyst composites were prepared using simple heteroagglomeration by applying attractive electrostatic forces between the nanoparticles with an opposite surface charge. The Fe3O4/SiO2/TiO2 photocatalysts were synthesized in an aqueous slurry solution containing Fe3O4/SiO2 and TiO2 nanoparticles under pH 5 conditions. Meanwhile, Fe3O4/SiO2 was prepared by a simple procedure via a coprecipitation of iron(II) and iron(III) ion mixtures in ammonium hydroxide and was leached by sodium silicate. The synthesized samples were investigated to determine the phase structure, the magnetic properties, and the morphology of the composites by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), respectively. The results indicated that the composites contained anatase and rutile phases and exhibited a superparamagnetic behavior. Fe3O4/SiO2 particles, which were of the aggregation spherical form at 20 nm in size, were successfully attached onto the TiO2 surface. The catalytic activity of Fe3O4/SiO2/TiO2 composites was evaluated for the degradation of methylene blue under ultraviolet (UV) irradiation. The presence of SiO2 as a barrier between Fe3O4 and TiO2 is not only improves the photocatalytic properties but also provides the ability to adsorb the properties on the composite. The Fe3O4/SiO2/TiO2 (50% containing TiO2 in composite) were able to eliminate 87.3% of methylene blue in water through the adsorption and photocatalytic processes. This result is slightly below pure TiO2, which is able to degrade 96% of methylene blue. The resulting Fe3O4/SiO2/TiO2 composite exhibited an excellent ability to remove dye from water and it is easily recollected using a magnetic bar from the water. Therefore, they have high potency as an efficient and simple implementation for the dye effluent decolorization of textile waste in slurry reactor processes."

"It is widely use ofair-conditioning systems in Thailand due to its location. It is located in atropical zone with relatively high temperatures all year round, with highhumidity and high intensity of sunlight. In order to save electrical energy forair-conditioning systems, preventing heat transfer into the building isrequired. The objective of this study is to investigate the physical andthermal properties of concrete blocks. An attempt is made to increase heatresistance of concrete blocks. Foam beads (0-0.30% by weight) and kaolin (0-70% by weight) wereadded in concrete block mixture to increase discontinuous voids in concrete.Compressive strength and water absorption of concrete blocks were tested. Thetesting results indicated that compressive strength decreased when foam beadsand kaolin were added. Water absorption increased when foam beads were added.In contrast, the more kaolin added the less water absorption. The thermalconductivity coefficient of concrete blocks was also investigated. The resultsconfirmed that the higher the amount of foam beads or kaolin added, the higherthe thermal resistance of concrete blocks. Thermal time-lag behavior was alsoinvestigated. The results indicated that concrete block with kaolin took thelongest time in heating and took the shortest time in cooling. These propertiesare good for heat prevention in hot climate regions. These concrete blockswhich were developed and tested in this research conform to the Thai IndustrialStandard. Finally, it can be concluded that because of its thermal behavior,concrete block with kaolin is a suitable energy-saving concrete block for hotand humid climates."