Jurnal Rekayasa Kimia & Lingkungan
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Extraction of Tannin from Jamblang Leaves (Syzigium cumini) with Ethanol Solvent to Reduce Phenols in Phenol-Formaldehyde in Wood Adhesives
No full textPhenol formaldehyde is one of the adhesives often used in wood processing, such as panels, particle boards, fiberboards, plywood, and others. However, the implementation of phenol formaldehyde adhesive has been greatly limited because of its non-renewability and toxicity. Modifying phenol formaldehyde adhesives is needed to reduce formaldehyde emission by adding tannin to the adhesive mixture. This study aims to extract tannin compounds from Java plum leaves with ethanol as a solvent for adhesive mixture. The adhesive implementation on plywood was also prepared, with various tannin content in the range of 10%-50%. The obtained data from tannin extraction from Java plum leaves are tannin yield, functional groups, total phenolic content, viscosity, and compressive test on plywood. The highest tannin yield and content are 46.70% and 27.88 mg/L, respectively, obtained at the weight ratio 1:5. At the same time, products of tannin-phenol formaldehyde have a viscosity as SNI 1987 standards for wood adhesives, namely in the range of 0.68-0.71 poise, while the result of the compressive strength is in the range of 0.02-0.05 N/mm2 and has met the requirement of SNI 1998 standards. Therefore, the tannin from Java plum leaves is a promising substitution of phenol in phenol formaldehyde in some aspects of the wood processing industry
Synthesis of Sulphonated Carbon Catalyst from Coconut Shell and its Application in Esterification of Free Fatty Acid in Used Cooking Oil
Full text linkCoconut shells are a prevalent agricultural waste product in Indonesia. Currently, there is a trend toward developing heterogeneous catalysts for the esterification reaction of vegetable oils to produce biodiesel. These catalysts are made from biomass carbon. This research aims to investigate the effectiveness of using carbon precursors derived from coconut shells to create a heterogeneous acid catalyst for the esterification of waste cooking oil (WCO). Another objective is to identify the optimal esterification reaction conditions catalyzed by the developed sulfonated carbon catalyst, which exhibits the highest performance in converting free fatty acids (FFA). The coconut shells were carbonized using conventional methods and functionalized with concentrated sulfuric acid through dry impregnation. This process was conducted under various sulfonation conditions. The varied preparation parameters included the carbon-acid ratio (1:7.1, 1:10, 1:12.8, and 1:15.7% w/v), contact time (1 to 4 days), and calcination temperature (270C, 340C, and 450C). The charcoal and catalyst developed in this research were characterized through composition analysis using X-ray fluorescence (XRF) and crystal phase analysis using X-ray diffraction (XRD). The best catalyst preparation conditions were determined to be a carbon-acid ratio of 1:15.7% (w/v), a contact time of 3 days, and a calcination temperature of 340C. The optimal esterification reaction conditions were achieved using a mole ratio of methanol to WCO of 12:1, with a catalyst amount of 1.6%, for a duration of 1 hour at a temperature of 60C. This reaction resulted in a conversion rate of 84.6%
Synthesis of Zeolite from Fly Ash and Bottom Ash and Application for Biodiesel Transesterification
Full text linkBurning coal in a Coal-Fired Power Plant produces by-products like fly ash and bottom ash. Zeolite synthesized from the ash in Teluk Sirih Coal-Fired Power Plant was applied as a catalyst in the biodiesel transesterification reaction. Zeolite synthesis used the hydrothermal method with acid pretreatment. The operating conditions for fly ash zeolite are a 2.4-molar ratio SiO2/Al2O3 and a crystallization time of 6 hours. The bottom ash zeolite used a 2.0-molar ratio SiO2/Al2O3 and a crystallization time of 8 hours. The performance test of the synthesized catalyst was carried out in the transesterification reaction using waste cooking oil as a raw material with a free fatty acid content of 0.7%. The synthesized catalyst was characterized using x-ray diffraction, scanning electron microscope, and Bruneuer-emmet-teller. The biodiesel with the highest yield was analyzed based on SNI 7182: 2015. The synthesis results of the catalyst produced type A zeolite, shown by the typical X-ray diffraction pattern and supported by the morphological test results using a cube-shaped. The surface area of zeolite fly ash and bottom ash is 12.87 m2/g and 5.13 m2/g. The test showed fly ash zeolite had the highest biodiesel yield of 89.66%. Based on the characterization using SNI 7182: 2015, the color and free glycerol met the standards, while density 40 C, kinematic viscosity 40 C, acid number, total glycerol, methyl ester content, and water content did not meet the standards
A New Superabsorbent Polymer Derived from Acrylamide and Fine Coal
Full text linkThe fine coal was a by-product of the mechanical coal processing used at the coal mine, that can be converted to added value materials. The objective of this study to obtain the new superabsorbent polymers (SAP) derived from fine coal. The SAP synthesis was conducted via a free radical polymerization with various percentage of fine coal is 10; 25; and 40% of acrylamide and fine coal total. The copolymerization was carried out for 3 h at 70 C, followed by subsequent saponification with 1 M NaOH for 2 h. The superabsorbent composite was characterized by Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). FTIR spectra revealed that the acrylic acid was successfully grafted onto the fine coal backbone. As shown by SEM imaging, the resulting surface was homogeneous and exhibited an interconnected pore structure. The maximum absorption capacity was found for SAP C2, which had a composition of 25% fine coal, 75% acrylamide, 0.11% N,N-methylene-bis-acrylamide (MBA), and 1.11% ammonium persulfate. The absorption capacities for the unsaponified and saponified SAPs were 42.36 and 617.86 g/g, respectively. The maximum water absorption capacity of the superabsorbent polymer was achieved at pH 6.5. Based on water absorption capacity, this product is suitable for soil conditioner or agricultural application
Quantitative Structure-Activity Relationship Study of Fatty Acid Derivatives as Lubricant Additive
Full text linkFatty acid compounds and their derivatives have been known in tribology as a source of bio-lubricant raw materials. New compounds were developed computationally to sort out the physical properties of the desired lubricant additive before synthesis in the laboratory. In this study, the correlation between the chemical structure of fatty acid derivative compounds and their physical properties through the quantitative structure-activity relationship (QSAR) using the density functional theory (DFT) was determined. QSAR model resulted in two linear regression equations for the wear rate performance test at (1) the value of the weld load with 5%, 500N variation and (2) the value of the wear scar diameter 5%, 150N variation. Validation of the regression model was conducted using the leave-one-out (LOO) method. The new additive lubricants were designed using the obtained QSAR models of the wear rate performance test with the descriptor of total energy, dipole moment, and softness. Stearoyl diethanolamine compound was proposed as a lubricant additive with the best performance parameter of weld load and wear scar diameter at 298.03 kg and 0.29 mm respectively. The percentage performance of stearoyl diethanolamine for weld load and wear scar diameter was increased by 24.18% and 47.60%, respectively
The Use of Papaya Seeds (Carica papaya L.) as a Biocoagulant in the Dairy Industry Liquid Waste Treatment Process with the Coagulation-Flocculation Method
Full text linkDairy industry discharges wastewater characterized by high values of Total Suspended Solid and turbidity. The waste is commonly processed using chemical coagulants which negatively impact humans health and the environment. Papaya seeds can be used as a coagulant as their positively charged proteins that can bind the negatively charged particles allowing the resulting floc to settle and clear water to be obtained. The goals of this study are to determine the characteristics of the dairy industry wastewater before and after flocculation coagulation, the characteristics papaya seed biocoagulant, the effect of the biocoagulants dosses, particle sizes, and stirring speed on the turbidity and the Total Suspended Solid of the dairy industry wastewater, and the performance of the biocoagulants in processing the dairy industry waste using Sludge Volume Index and Sludge Mass. The treatments applied in this research are in terms of doses (250 mg, 500 mg, and 750 mg), particle sizes (60,120, and 230 mesh), fast stirring speeds (120 rpm, 180rpm, 200 rpm for 1 minute), and slow stirring speeds (10 rpm, 30rpm, and 50 rpm for 20 minutes) all of which were expected to reduce the wastes turbidity and the number of Total Suspended Solid. This study finds that the treatment with the highest reduction of Total Suspended Solid is D3P3KP2, which decreased turbidity from 754 NTU to 92 NTU. The treatment with the highest reduction of Total Suspended Solid was D3P3KP2 which decrease the Total Suspended Solid from 124 mg/L to 79 mg/L. The performance of the papaya seed biocoagulant of D3P3KP2 treatment is considered good as the acquired highest value of the Sludge Volume Index is 83.13 ml/g and as the procured lowest value of the Sludge Mass is 81.48%
Utilization of Waste Banana Peels and Corn Cobs as Substrates in Neurospora sitophila Fermentation for Production of Natural Yellow Dyes
Full text linkIn the current situation, biomass gasification has become a major interest in producing clean energy and green chemicals. By gasification, the biomass can be converted to synthetic gas (syngas) for many purposes. However, syngas with high tar content can cause pipeline fouling and disturb the operation of downstream equipment. To reduce tar content, a two-series wet scrubber was installed for syngas cleaning produced by palm kernel shell gasification. Firstly, the gasification is operated at a temperature range of 500 600oC and 700 800oC to determine the conditions where the lowest tar syngas is produced. After that, the wet scrubber is installed with a variety of solvents including isopropyl alcohol, water, used cooking oil, and used lubricating oil. The results show that the lowest tar syngas was produced at a temperature of 800oC with a tar yield of 0.165 g/kg biomass. Meanwhile, in the same condition, isopropyl alcohol delivers the most substantial impact on tar removal efficiency, whereas used lubricating oil results in less impact. The use of isopropyl alcohol resulted in 99.25% tar removal effectiveness while lubricating oil yielded just 50.32%
The Effect of Heat Tracing Installation for Wax Prevention on Onshore Buried Swampy Pipelines
Full text linkTransporting crude oil using pipelines is a widely adopted method globally. In one segment owned by PT. XYZ, especially in swampy areas, the fluid temperature tends to drop below the wax appearance temperature (WAT) during oil transportation. This is due to the relatively low temperature in swamp areas caused by heat loss to the environment. The solubility of paraffin in crude oil drastically decreases as fluid temperature drops, causing wax molecules to precipitate and deposit on the cold pipe walls. PT. XYZ employs chemical treatment by adding a pour point depressant (PPD) to lower the pour point temperature (PPT). However, PPD is effective only at certain temperatures, necessitating a study for alternative treatments. Another method involves installing heaters on the pipeline to reduce the viscosity of transported crude oil and enhance its flowability, either through direct heating or heat tracing using insulation with low thermal conductivity. Therefore, in PT. XYZ's case, an analysis is required to identify locations where fluid temperature decreases occur to ensure precise heater installation. Various software tools, including OLGA, have been developed to predict and describe wax deposition phenomena and temperature decreases along the pipeline. OLGA software can simulate locations of fluid temperature decreases in the pipeline, estimate heat loss along the pipeline, and simulate heat tracing technologies to prevent wax deposition. Simulation results indicate that wax deposition can be prevented by installing skin effect heat tracing with a heating power of 15 W/m and insulated with 2-inch aerogel, maintaining the oil temperature downstream at 157.34F, well above the desired 115F threshold
Comparison Effect of Pyrolysis of Eucalyptus Pellita Bark and Empty Fruit Bunches of Oil Palm to Bio-Oil
Full text linkThe use of eucalyptus pelitta (EP) biomass waste and empty fruit bunch of oil palm(EFB) as raw materials for bio-oil is expected to overcome the existing solid waste problems, reduce pollution due to air pollution, and can produce gas and bio-oil which have potential. as new and renewable energy. This study aims to determine the effect of the type of raw material and temperature regulation on the results of pyrolysis products and the characteristics of the resulting bio-oil. The set temperatures used were 300C, 350C, 400C, 450C, and 500C with the raw materials being Eucalyptus pellita (EP) bark biomass and empty fruit bunches of oil palm (EFB). Pyrolysis that occurs with the equipment configuration used a heating rate of 7-14C/minute, where the main reaction of pyrolysis occurs at a temperature of 150C to 270C so that the set temperature does not have a large effect on the yield or characteristics of bio-oil. EP pyrolysis produced an average bio-oil yield of 41.64%, while EFB pyrolysis produced an average bio-oil yield of 46.72%. Bio-oil produced by pyrolysis of EP has a characteristic average value for density of 1.062362 gr/mL, viscosity of 2.1749 cP, and pH 2-3. Meanwhile, bio-oil produced by pyrolysis of EFB has a characteristic average value for density of 1.043146 gr/mL, viscosity of 1.3582 cP, and pH 3-4. EP bio-oil has a composition of C7-C10 carbon, while EFB bio-oil has a composition of C6-C19 carbon
The Study of Using Vinegar Acid as a Dangke Coagulant Alternative
Full text linkCoagulated by papaya sap, dangke is known as a traditional dairy product belonging to the household-scale processing business in Enrekang, South Sulawesi Province, Indonesia. Vinegar is another coagulant that can be used in making dangke. This study aimed to utilize vinegar as an alternative dangke coagulant other than papaya sap, to analyze the texture of dangke, to use different salt concentrations while making dangke with vinegar, to perform proximate tests, and to conduct organoleptic tests. Dangke was made from 1 L cow's milk mixed with 5 mL of vinegar. For roughly 20 minutes, the mixture is cooked at 6570C while being stirred. The curd was separated from the whey and then shaped into dangke. Dangke was then soaked for 75 minutes in varied salt concentrations of 2%, 3%, and 4%. The texture analyzer (softness) result of this dangke was 125.974 g/s. It was close to the texture of traditional dangke. Proximate analyses were performed. The result that comes close to the result of traditional dangke was 3% salt-soaked dangke with a moisture content of 35.82%, an ash content of 1.44%, dissolved protein content of 0.47%, and fat content of 5.06%. An organoleptic test of preference for dangke vinegar was also carried out. The results of this study are expected to be utilized by local industries having difficulties in obtaining papaya sap as a dangke coagulant