Aceh International Journal of Science and Technology
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Calcined Aceh Bovine Bone (Bos indicus) Intercalated Lithium as An Inorganic Base Catalyst for Transesterification of Castor Oil
Get PDFRealizing abundant availability of local bovine bone wastes in Aceh Province, Indonesia, this study is subjected to take competitive advantages from the local bovine bone waste for preparing an inorganic catalyst preparation. In detail, calcined Aceh bovine bones were successfully intercalated lithium through an impregnation method resulting in the inorganic base catalyst, which showed promising activity in the transesterification of castor oil. Prior to the experiment, the Aceh bovine bone waste was calcined at 900 oC in the air atmosphere for 4 hours, led to forming crystalline phases of hydroxyapatite [Ca5(PO4)3(OH)] and calcium oxide [CaO]. Also, the chemical modification of calcined bovine bone with lithium precursor has enhanced the physicochemical properties of the inorganic base catalyst. Finally, the intercalated Aceh bovine bone has shown a feasible activity in transesterification of castor oil into biodiesel, which yielding methyl ricinoleate as the main product
A Simple Method to Develop a Formula for Estimating Concentration Time of Drainage Design
Get PDFConcentration time of rainfall is an important aspect to determine drainage design. A general rational formula is used to determine design flood or peak flow in urban drainage planning, especially for storm sewer design. The use of this balanced formula requires rainfall intensity, whose duration of rain is equal or more than the time of concentration. This time of concentration is determined using an estimation formula whose formation requires measurement data of the time of concentration. This study introduces how to measure the time of concentration using the concept of-rational-hydrograph, in which peak flow occurs at the time of concentration. To fulfill the aim of this research, an experimental of catchment area planted with Zoysia Japonica grass and showered with a rainfall simulator was conducted. The length of the flow path on the land, L, given in 5 variations, namely 50 cm, 100 cm, 150 cm, 200 cm, and 250 cm, was used. The slope of the land, S, is given in 3 variations, namely 2.8 %, 5,6%, and 8.8%. For each variation of L and S, the experimental catchment area was poured with a fixed rainfall intensity, which is 60 mm/hour. The flow was measured every 5 minutes intervals. Then, from the relationship of flow and time, a rational hydrograph was formed, from which the time of concentration, Tc, was deduced. This Tc value was treated as the measured Tc to form the Tc estimation formula using the regression formula. The formula is Tc = 3.543 + 1.211 L 17.119 S, with the coefficient of determination R2 = 0.98. These results show that the determination of Tc using the concept of the rational- hydrograph is acceptable. This formula applies to L and S values greater than zero and applies to land covered by Zoysia Japonica grass. Further research is needed for other types of land cover to validate the formula obtained in this research
Land Arrangement for Citronella (Cymbopogon Nardus) and Arabica Coffee in the Cultivation Area in Gayo Lues District, Aceh Province Indonesia: A Land Suitability Approach
Get PDFGayo Lues District is known as Citronella and Arabica coffee producer in Aceh province, Indonesia. This paper aims to manage Citronella and Arabica coffee's land arrangement in the Gayo Lues District's cultivated area. This implementation is aimed at maintaining the peculiarities of citronella products and Arabica coffee. Thus, the two commodities must be separated in terms of allocated sites. The altitude for the area is 200-2,000 meters above sea level, consisting of ten classes, and the type of soils are Entisols, Oxisols, Inceptisols, and Ultisols. The area's slope between 0- to 40% (4 classes) was used to delineate the land units. There are 49 land units observed within the cultivated area of 160,017.17 ha. The guidelines for land suitability classification by the Ministry of Agriculture for Citronella and Center for Coffee and Cocoa Research, Jember for Arabica coffee were utilized. The results showed that 58,275.5 hectares of land were suitable for citronella, and 13,765.75 ha has been planted. The actual land suitability of citronella inside the area of 58,275.5 ha is suitable (S2 class) and marginally suitable (S3-class) and not suitable (N-class) with limiting factors are temperature, water availability, erosion hazard, and nutrient retention. This land suitability can be improved by providing inputs to increase the level of suitability with temperature, water availability, and erosion hazard (slope) limiting factors. Also, 48,765.3 hectares can be developed for Arabica coffee, and 4,653.5 ha has been planted. The actual land suitability for Arabica coffee is Suitable, Marginal Suitable, and Not Suitable, limiting the soil's physical properties (adequate soil depth), slope, and chemical properties of the soil. Once repaired, the land's suitability becomes Suitable (S1-class) (without limiting factor), Suitable, and marginal suitable with the slope as a limiting factor. There is an area of 44,509.75 hectares of land at 200-1,400 m above sea level within the cultivation area developed with a Citronella. There is an area of 44,111.8 ha at the height of 800-2,000 m above sea level, potentially for Arabica coffee
Adsorption Of Cd(II) Ions From Aqueous Solution By A Low-Cost Biosorbent Prepared From Ipomea Pes-Caprae Stem
Get PDFThe use of a low-cost biosorbent prepared from Ipomoea pes-caprae stem for the adsorption of Cd(II) ions from aqueous solution at different contact times, biosorbent sizes, pH values, and initial Cd(II) ions concentration solution was investigated. The biosorbent was analyzed using Fourier-transform infrared spectroscopy (FT-IR) to find important IR-active functional groups. A scanning electron microscope (SEM) was used to examine the biosorbent morphology. The experimental results showed the highest Cd(II) ions adsorption was 29.513 mg/g under an optimal condition as initial Cd(II) ions concentration of 662.77 mg/L, 1 g dose, 80-min contact time, pH 5, 75 rpm of stirring speed, 1 atm, and 30 oC. Cd(II) ions' adsorption kinetics obeys the linearized pseudo-second-order kinetics (R2 = 0.996), and the adsorption capacity is based on the optimal condition, and the rate attained was 44.444 mg/g and 0.097 g/mg. Min, respectively. Besides, the adsorption isotherms were very well fitted by the linearized Langmuir isotherm model, and the monolayer adsorption capacity and pore volume determined was 30.121 mg/g and 0.129 L/mg, respectively. These results indicated the chemisorption natur
An Assessment of the Spatial Comfort at the Open Piazza of Baiturrahman Mosque, Banda Aceh, Indonesia
Get PDFThe Baiturrahman Grand Mosque is well-known as the identity of Banda Aceh town, Indonesia. The extensive renovation was carried out in 2015 to the Mosque, presenting an open piazza coated with glossy white marble replacing the previous greeneries and grass. This change creates a much different thermal sensation of the prior environment. This condition also invites the contrast to respond and define spatial comfort, including thermal and visual comfort. Therefore, this study conducts an assessment of thermal and visual comfort at the open piazza, which was done through field measurements. The outdoor thermal comfort was calculated using the equations proposed by Sangkertadi that are appropriate for the tropics. The visual comfort was examined using the De Boer glare scale. The result shows the discomfort appearance for both thermal and visual comfort. The study gives recommendations, such as planting greeneries, providing more shades for achieving lower outdoor air temperature. Replacing the glossy marble with the diffusing and rough surface will reduce the glare for getting the more acceptable visual comfort against the marbles
Analysis of Crystallinity and Physical Properties of the Bio-solar Gemstone
Get PDFAbstract Bio-solar is one of the natural gemstones found in the province of Aceh in Indonesia. A recent study suggested that this gemstone could be considered as a vesuvianite type of gemstone. Nevertheless, detail information of this bio-solar gemstone is still unknown. We do not know whether the bio-solar gemstone is crystalline or amorphous. The specific gravity and the hardness of this gemstone are also still unknown. This information is essential to determine the quality of a gem. To answer those questions, we have used x-ray diffraction to study the bio-solar gemstone from the province of Aceh in Indonesia. The physical properties (specific gravity and hardness) of this gemstone have also been measured. We found that the bio-solar gemstone is composed by CaO, SiO2, MgO, Al2O3, Fe2O3, and TiO2 phases. Our results revealed that the bio-solar gem is a crystalline material, not amorphous. The average crystallite size of this gemstone is found to be 353 (35 nm). Moreover, the specific gravity of bio-solar gemstone is found to be 3.09 3.34. Its hardness is 3 to 4 mohs. Thus, the bio-solar is a good quality gemstone. Our finding confirmed that the bio-solar could be classified as a vesuvianite gemstone
Activated Bentonite Modified-Carbon Paste Electrode for Determination The Level of Copper Ion (Cu2+) in Tomato
Get PDFVoltammetry is an electroanalytical method measure current as a function of applied potential. The working electrode in the voltammetry method dramatically affects the result of the electrochemical analysis. Modification of the working electrode can improve measurement performance. In this research, the carbon paste electrode (CPE) was modified with Bentonite (CPEB) to determine copper's level using differential pulse voltammetry technique. CPE and CPEB were used as working electrodes, handmade Ag/AgCl as a reference electrode, and Pt wire as the counter electrode. The measurement parameters were optimized, including the composition of bentonite in carbon paste and scan rates. Furthermore, the measurement conditions were validated, involved linear concentration range, detection limit (LoD), the limit of quantization (LoQ), repeatability, and recovery. The results showed that bentonite's optimum composition was 40% of the total weight of graphite and activated bentonite. The scan rate optimum for Cu2+ measurement was obtained at 20 mV/s with CPE and became faster to be 25 mV/s with CPEB. The linearity of the standard solution measurement of Cu2+ using CPE was in the range of 5 to 100 g/L and changed to 5 to 500 g/L using CPEB. LoD and LoQ values of standard solution Cu2+ measurement with CPEB were slower than CPE. The Horwitz ratio calculation was smaller than two for both CPE and CPEB. The recovery of Cu2+ standard measure in sample solution as the matrix was obtained 93,49 6,39%. According to the Decree of the Ministry of Health Number, the level of Cu2+ in the tomato sample was found 6.019 0.69 mg/kg, which is over than threshold value of Cu2+ (5 mg/kg) 03725/B/SK/VII/89
Utilization of Oyster Shells as a Substitute Part of Cement and Fine Aggregate in the Compressive Strength of Concrete
Get PDFThe compressive strength of concrete depends on the physical characteristics of the concrete forming materials. Oyster shells originating from Krueng Neng, Aceh Besar are very abundant, left unattended by fishermen, causing pollution of the surrounding environment. Oyster shell dust contains CaO, which can be used as a partial substitution of cement. Therefore, it is necessary to study oyster shell ash as cement replacement and fine aggregate in concrete production. This research aims to determine the compressive strength of concrete using shell ash as cement replacement and fine aggregate. The oyster shells were obtained from Krueng Neng, Lamjamee Village, Jaya Baru, Aceh Besar District. The oyster shells were crushed with a Los Angeles Test machine and sieved with sieve size 2.36 mm for fine aggregate and sieve #200 for cement replacement. The water-cement ratios (w/c) were 0.4, 0.5 and 0.6. The results showed that concrete's compressive strength with 5% cement replacement level was higher than the concrete with cement only. Meanwhile, for other replacement levels, the compressive strengths of concrete specimens were lower than control specimens
First Order Kinetics of Biodiesel Synthesis Using Used Frying Oil through Transesterification Reaction
Get PDFThis research aims to study the first-order kinetics of biodiesel production from used frying oil (UFO) through transesterification with methanol. Used frying oil was collected from fried peddlers around the campus of the University of Lampung. Technical grade methanol and NaOH catalyst were purchased from a local chemical supplier. The experiment was carried out with 100 ml of UFO at various combinations of oil to methanol molar ratio (1:4, 1:5, and 1:6), reaction temperatures(30 to 55oC, the ramping temperature of 5o C), and reaction time of 0.25 to 10 minutes. First-order kinetic was employed using 126 data pairs (87.5%). The acquired kinetic model was validated using 18 data sets (12.5%) observed at a reaction time of eight min. Results show that biodiesel yield was increased with reaction time, its molar ratio, and temperature. The maximum return of 78.44% was achieved at 55oC and molar ratio of 1:6. The kinetic analysis obtains the reaction rate constant (k) in the range of 0.045 to 0.130. The value of k increases with the reaction temperature and molar ratio. The analysis also reveals the average activation energy (Ea) of the UFO transesterification reaction with methanol and NaOH catalyst to be 21.59 kJ/mol. First-order kinetic is suitable to predict biodiesel yield from UFO because of low %RMSE (3.39%) and high R2 (0.845
Enrichment of Sawahlunto Clay with Cation Ca2+ and Cu2+ and Preliminary Test of its Catalytic Activity in CPO Transesterification Reaction
Get PDFThis research is aimed to examine the catalytic activity of Sawahlunto clay, which is enriched with Ca2+ and Cu2+ transesterification of Crude Palm Oil (CPO) to produce biodiesel. Based on the results of the analysis with X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD), Sawahlunto clay consists of about 61% Si and 24% Al with a Si/Al mole ratio of 2.7 and typical clay mineral consisting of kaolinite and illite, another mineral fund was quartz and goethite. The mineral composition changes after calcination, where kaolinite and illite disappeared. Fourier Transform Infrared (FTIR) analysis shows that calcination can remove the organic compounds Sawahlunto clay; thus, the clay was used without calcination for the next step. Clay samples can be enriched with Ca2+ ions and Cu2+ ions without damaging their mineral composition, where more Cu2+ ions are loaded than Ca2+ ions. The Sawahlunto clay enriched with Ca2+ ions showed a slightly better catalytic activity in the transesterification of crude palm oil (CPO) than its parent clay; when enriched with Cu2+ ions, the catalytic activity did not appear at all. However, the homogeneous counterpart of such catalyst, calcium nitrate, was still the most active and selective compared to all other