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The palm oil industry in Indonesia produces abundant production waste, including solid, liquid, and gas forms. The management of palm oil mill wastewater (POME) is still not optimal. The purpose of this study was to analyze the remediation of palm oil wastewater using a consortium of Chlorella vulgaris and Nannochloropsis oculata. The study analyzed (COD), total suspended solids (TSS), pH, salinity, and microalgae cell density at various POME concentrations (0%, 25%, 50%, 75%, and 100%). The results showed that a POME concentration of 50% produced the highest total microalgae cell density at 774 x 10³ cells/mL. A significant decrease in salinity (18%) was observed at a POME concentration of 75% with a microalgae consortium. The effective pH for the microalgae consortium is between 8-9. In addition, the microalgae consortium effectively reduced COD by 70.3% and reduced TSS by 46.74%. Therefore, the consortium of Chlorella vulgaris and Nannochloropsis oculata has potential in the remediation of POME waste.

Polyeugenol is a polymer synthesized from renewable natural resources and has potential as a supercapacitor electrode material. Polyeugenol was modified by the addition of diallyl phthalate to increase structural density and thermal stability and the addition of sulfonate groups to increase ion exchange capacity and electrical conductivity. This research begins with the synthesis of eugenol-diallyl phthalate copolymer (PEGDAF) carried out by cationic polymerization using BF3O(C2H5)2 catalyst and sulfonation of eugenol-diallyl phthalate copolymer (SPEGDAF) using sulfuric acid. The synthesis of PEGDAF in the form of pink solids with a yield of 68.44%, a molecular weight of 6739.99 Daltons, and a melting point of 85°C, FTIR analysis showed that the formation of PEGDAF was characterized by the loss of vinyl groups with the absence of C=C alkene wavenumber absorption which is the wavenumber absorption of eugenol and diallyl phthalate, respectively 1640 cm-1 and 1647 cm-1 and TGA with a mass loss of 5% and 10% at 176°C and 219°C. SPEGDAF results in dark purple solids with a sulfonation degree of 17.18% and a cation exchange capacity of 0.4186 meq/g, molecular weight 8342.25 Daltons, melting point 114°C. Analysis using FTIR showed the presence of sulfonate groups with the resulting absorption peaks of 1218 cm-1 (S=O), 1065 cm-1 (S-O), and 578 cm-1 (C-S) and TGA with a mass decrease of 5% and 10% at temperatures of 169°C and 215°C. Potential test of supercapacitor electrode material with Cyclic Voltammetry and Electrochemical Impedance Spectroscopy obtained a specific capacitance value of 3.23 × 10-3 F/g and ion conductivity of 7.58 × 10-6 S/cm. [ABSTRACT FROM AUTHOR]

The paper focuses on analyzing the energy and financial viability of a dual-fuel gas turbine generator (GTG) system, which operates on both diesel and natural gas. The study evaluates the GTG's performance in a gas processing facility located in East Java, which utilizes three GTGs configured to run two at a time with one on standby, each with a capacity of 13.7 MW. The exhaust gases from these GTGs are currently unused, representing a potential energy resource for the facility's steam requirements. To address this, a Heat Recovery Steam Generator (HRSG) system is proposed to harness the exhaust gas heat, producing medium-pressure (MP) and low-pressure (LP) steam. The study compares the thermal efficiency, power output, and cost-effectiveness of natural gas versus diesel fuel, considering their respective exhaust temperatures and flow rates. Results indicate that natural gas provides higher thermal efficiency, lower fuel consumption, and reduced emissions compared to diesel. Additionally, the HRSG using natural gas can produce more steam, enhancing the facility's overall efficiency. Financially, using natural gas could result in substantial savings, amounting to approximately $3,255.1 per hour. This analysis concludes that natural gas offers a more costeffective and environmentally friendly solution for GTG operations, optimizing both the steam production and power generation capacity of the facility. [ABSTRACT FROM AUTHOR]

The bacteria-resistant plastic polymer industry is growing rapidly due to promising research on food contamination. The thiol-ene copolymers Eugenol-Trithiol Methylenebisacrylamide (E3TMBA) and Eugenol-Trithiol, Allyl Eugenol (E3TAE) were synthesized via photopolymerization. Both copolymers possess high thermal stability, which is crucial for maintaining their durability when used with high-temperature foods. The copolymers demonstrated a 5.0% mass loss (T5) at 179°C for E3TMBA and 255.9°C for E3TAE, as well as the formation of ash products at above 500°C. Both copolymers have mechanical properties and exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus, enhancing their food packaging potential. [ABSTRACT FROM AUTHOR]

Mill scale is a by-product of hot rolling steel generated in a rolling mill and has the potential to be transformed into hematite. Owing to hematite's many uses; mill scale has a high economic value and may be used as a battery anode. The impact of CaCO3 pellet quantity and calcination time on hematite purity, as well as the effect of deposition duration and voltage on coating thickness. The calcination duration has a considerable effect on the purity of the resulting hematite, while the addition of CaCO3 pellets lowered the purity by around 6%. Attaining the thickest hematite coating on an aluminium surface required a 40 V treatment and a deposition time of 30 minutes. Alternately arranged aluminium ions (Al3+) and oxide ions (O2- ) form an ionic connection. Whereas aluminium ions on the surface of aluminium are positively charged, oxide ions are negatively charged in order to generate an electrostatic interaction. During the discharge phase, the voltage decreased from 1.02 to 0.70 V. This research contributes to the development of more efficient and effective manufacturing procedures for hematite and its battery anode applications. [ABSTRACT FROM AUTHOR]