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Rahmahwati, Cut Aja
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Pembuatan Kulit Biosintetis dari Nata De Banana menggunakan Polyurethane dan Anti Bakterial Chitosan Nurmila, Nurmila; Rahmahwati, Cut Aja; Elwina, Elwina
Jurnal Teknologi Vol 25, No 1 (2025): April 2025
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/teknologi.v25i1.6373

Abstract

Organic synthetic leather is engineered leather created with raw materials that can be found around the human environment in the form of fruits or fruit peels which have high fiber so that they can deal with organic waste, with organic synthetic leather the population of animals killed for their skins reduced so as to maintain the survival of animals. This study aims to determine the effect of the addition of polyurethane (PU) and chitosan on the characteristics of the resulting leather. With variation (Polyurethane A) 2 : 1 (Polyurethane B), namely 15 mL, 30 mL, 45 mL, 60 mL, 75 mL and chitosan 2 g, 4 g, 6 g, 8 g, 10 g. The addition of PU affects the elasticity and hardness of the final leather product and chitosan has the effect of inhibiting bacterial growth and fungus on synthetic leather. The organoleptic test for all synthetic leather does not meet SNI standards. Based on the results of anti-bacterial testing (colony counter) there were the highest bacteria in the lowest chitosan variation, namely 2 grams and the lowest bacteria in the highest chitosan variation, namely 10 grams. The result of the tensile strength test is that the highest tensile strength value is produced by PU (2:1) at 50:25 ml polyurethane volume of 3.432 MPa with 21.36% elongation and the lowest tensile strength value is produced by PU (2:1) at 15 volume : 8 mL of 16.181 MPa elongation 21.42%.
The Catalytic Performance of Vanadium–Nickel Supported on Zeolite for the Conversion of Crude Palm Oil into Short-Chain Hydrocarbons Rahmahwati, Cut Aja; Salmyah, Salmyah; Sami, Muhammad; Sariadi, Sariadi
Jurnal Teknologi Vol 25, No 2 (2025): Agustus 2025
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/teknologi.v25i2.7030

Abstract

The increasing global demand for fossil fuels, alongside declining domestic oil production, has intensified interest in renewable energy sources. Among Indonesia's abundant biomass options, crude palm oil (CPO) is a promising candidate for biofuel production due to its high triglyceride content and chemical similarity to petroleum. This study explores the catalytic cracking of CPO using a vanadium–nickel catalyst supported on natural zeolite, aiming to evaluate its physicochemical properties and catalytic performance in converting CPO into short-chain hydrocarbons for potential use as biogasoline. The catalyst was synthesized via wet impregnation of natural zeolite with ammonium metavanadate and nickel nitrate hexahydrate, followed by calcination. Characterization using Thermogravimetric Analysis (TGA), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) confirmed good thermal stability, crystallinity, and surface morphology. Catalytic cracking was performed at elevated temperatures under atmospheric pressure. The liquid products were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). The results showed that the catalyst successfully facilitated the breakdown of triglycerides, producing mainly medium-chain fatty acids. Pentadecanoic acid (C₁₅H₃₀O₂) was identified as the dominant compound, indicating partial cracking of CPO. However, the product composition still contained oxygenated species, suggesting incomplete deoxygenation. Consequently, the resulting mixture does not yet meet biogasoline specifications. These findings highlight the potential of vanadium–nickel/zeolite catalysts in biofuel conversion processes, while also emphasizing the need for further catalyst optimization or additional processing stages to achieve complete transformation into fuel-grade hydrocarbons.
Utilization of a Mixture of Peuyeumization Market Waste-Derived RDF (Refuse-Derived Fuel) and Coconut Shell Charcoal (CSC) into Bio-Briquettes with Coal-Calorific Value Elfiana, Elfiana; Intan, Syarifah Keumala; Ruhana, Ruhana; Rahmahwati, Cut Aja; Zaini, Halim
Jurnal Teknologi Vol 25, No 2 (2025): Agustus 2025
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/teknologi.v25i2.6887

Abstract

The accumulation of market waste and coconut shells poses a significant environmental challenge, necessitating effective management strategies by both local governments and academic institutions. This study explores the conversion of organic market waste into Refuse-Derived Fuel (RDF) through a dry fermentation (peuyeumization) process using 5% EM4 bio-activator over a 21-day incubation period. Concurrently, coconut shells were carbonized to produce high-carbon Coconut Shell Charcoal (CSC). Both RDF and CSC, ground to a 100-mesh particle size, were utilized to produce cylindrical bio-briquettes (7 cm height, 3.6 cm outer diameter, 1.6 cm inner diameter) using a compaction method. Various RDF:CSC ratios (0:100, 25:75, 50:50, 75:25, and 100:0) were tested with three concentrations of tapioca starch adhesive (6%, 8%, and 10%). The quality of the resulting briquettes was evaluated based on the Indonesian National Standard (SNI 01-6235-2000), assessing parameters such as moisture content, ash content, density, fixed carbon content, and calorific value. Combustion characteristics were further examined through ignition time and combustion rate measurements. The optimal briquette was produced at a 25:75 RDF:CSC ratio with 6% adhesive, achieving a weight of 30 g, density of 0.46 g/mL, fixed carbon content of 75.51%, moisture content of 5.25%, ash content of 5.91%, calorific value of 6117.38 cal/g, ignition time of 63.78 minutes, and combustion rate of 1.55 g/min. These findings indicate that the bio-briquettes meet the calorific standard of young coal, supporting their potential use as an environmentally friendly alternative fuel.
Co-Authors E. Elwina Elfiana Elfiana, Elfiana Elfiana, E Halim Zaini, Halim Harunsyah, Harunsyah Intan, Syarifah Keumala Nurmila, Nurmila Pardi Pardi, Pardi Prihatin, Nanang Reza Fauzan Ridwan, Ridwan Ruhana, Ruhana Salmyah, Salmyah Sami, Muhammad Sariadi Sariadi Satriananda, Satriananda