Jurnal Rekayasa Proses

Techno-economic analysis of process for separating saturated and unsaturated fractions from palm fatty acid distillate

Fadhli Halim — 2024-12-31

Palm fatty acid distillate (PFAD) can be used as a raw material for two types of polyvinyl chloride (PVC) thermal stabilizers: organotin and mixed organometal. To produce high-quality thermal stabilizers, PFAD must first be separated into saturated and unsaturated fractions. This research aims to develop and analyze the techno-economics of separating these fractions from PFAD through solvent crystallization using methanol. The study began with the development of a process flow diagram, including the selection of unit operations and equipment. Mass and energy balances for the developed process were then calculated. Investment and production costs were estimated and used to determine economic indicators. These calculations were performed using Aspen Plus and Aspen Hysys software. Utility requirements were primarily driven by solvent evaporation and condensation. From an environmental perspective, higher crystallization temperatures are preferable due to reduced fuel consumption and lower CO₂ emissions. However, higher crystallization temperatures resulted in a less pure unsaturated fraction, despite producing a larger quantity. The estimated investment for constructing a separation plant with the studied capacity and crystallization temperature range was between 13.6 and 13.9 million USD. Among the equipment, fired heaters and refrigeration compressors contribute the most to costs. The separation process at temperatures of -15°C and 0°C was found to be economically viable, with internal rates of return (IRR) of 36% and 49%, respectively. In contrast, the separation process at 10°C was not economically feasible. The findings of this study are expected to serve as a reference for the development of commercial-scale processes.

Differences in the molecule structure of natural rubber and thermal coagulant process based on FTIR analysis

Feerzet Achmad — 2024-12-31

Rubber is one of the most potential and abundant biological natural resources in Indonesia. This research was conducted to determine the content of compounds contained in rubber after coagulation by means of thermal coagulants. There are 2 (two) thermal coagulants used, traditional using firewood and modern using a laboratory oven. Variations in the weight of the latex used were 0.5 kg, 0.75 kg, 1 kg, 1.25 kg and 1.5 kg. Then the results of the thermal coagulant were subjected to the Fourier Transform Infrared (FTIR) test to see the compound content contained in the rubber. The results of the FTIR test on traditional thermal coagulants at high and medium heat and modern thermal coagulants in the oven showed the typical functional groups of rubber, namely the presence of C-H, C=C and C-C carbon bonds.

Filtration of Kutawaru Cilacap batik waste using fly ash activated by sulfuric acid

Arina Manasikana — 2024-12-31

The batik industry is one of the largest contributors to liquid waste. Batik liquid waste if not treated properly has the potential to increase disease and pollute the environment. Pollutant levels contained in the waste can be degraded by using fly ash as an adsorbent. Fly ash is obtained from Steam Power Plant waste. The purpose of this study was to determine the best concentration of sulfuric acid between 1M and 3M added to activate fly ash to reduce COD, BOD, TSS, color change and pH of Kutawaru batik waste. The research consisted of three stages: the first stage was the activation of fly ash by immersing it in a solution of 1M and 3M sulfuric acid with a ratio of 1:5 for 3 hours. Then, wash with water until the pH is neutral. Furthermore, the fly ash was dried using an oven at 105oC for 4 hours to a constant weight, resulting in sulfuric acid-activated fly ash. The second stage of the adsorption process, where batik waste was mixed with sulfuric acid-activated fly ash in a ratio of 5:1 for 3 hours, resulted in the waste after adsorption. In the last stage, testing of the waste before and after adsorption was carried out at the Cilacap Environmental Laboratory. The results showed that the best concentration of sulfuric acid for the activation of fly ash was 1M because it reduced COD, BOD and TSS by up to 90%. Changes in COD, BOD, TSS, color and pH of batik waste before and after adsorption using 1 M sulfuric acid-activated fly ash, namely COD 13678 mg/L to 1302 mg/L, BOD 8480 mg/L to 870 mg/L, TSS 460 mg /L becomes 47 mg/L, the color of the batik waste changes from black to yellow, and pH 9 becomes 7.

Thermogravimetric Analysis of Indonesian Low-Rank Coal: Optimization of Drying Temperature and Kinetic Modeling

Shofa Rijalul Haq — 2024-12-31

Drying high-moisture of low rank coal in the mining sector is essential for increasing energy efficiency and ensuring stability in its use as an energy source. This study aims to determine the optimal drying temperature and kinetic parameters for Indonesian low rank coal (i.e., lignite and sub-bituminous) using thermogravimetric analysis (TGA) under both isothermal and non-isothermal conditions. Coal samples were tested at three heating rates (5, 10, and 20°C/min) and three fixed temperatures (150, 200, and 250°C). Several drying kinetics models, including the Newton, Henderson and Pabis, Logarithmic, and Page models, were used to evaluate the drying characteristics of both coal types. The results indicate that the Page model provided the best fit, with the highest 𝑅² value and the lowest 𝜒² value, making it the most accurate model for describing coal drying rates under various conditions. The optimal drying temperature for lignite was 83.04°C, with an activation energy of 3224.04 J/mol, while for sub-bituminous coal, the optimal temperature was 109.65°C with an activation energy of 17972.83 J/mol. These findings support the optimization of the drying process in the industry, particularly for efficiently reducing coal moisture content without compromising energy quality.

Optimization of D-limonene and phenolic compounds extraction from local Indonesian orange peel using ultrasound-assisted extraction

Wa Ode Cakra Nirwana — 2024-12-31

Malang Regency is one of the orange plantation centers in East Java, Indonesia, and has been named Indonesia’s orange agrotourism area. Orange peel waste in Indonesia has not been utilized, even though orange peel contains valuable compounds, such as D-limonene and polyphenols. To date, studies on the extraction of D-limonene and total phenolic compounds (TPC) from Baby Java Pacitan orange (Citrus sinensis L.) and Keprok Batu 55 oranges (Citrus reticulata Blanco) has not been investigated. In this work, several factors affecting the extraction of D-limonene and total phenolic compounds from local Indonesian orange peels with ultrasonic assistance were investigated and optimized. The results showed that drying using a vacuum oven and agitation significantly increased the yield of D-limonene and TPC. The optimum condition for extracting D-limonene was a solid-solvent ratio (SSR) of 1:10 with an ethanol concentration of 96% for 40 minutes. Meanwhile, the optimum condition for extracting polyphenol compounds was a solid-solvent ratio of 1:10 with an ethanol concentration of 96% for 80 minutes. Under optimum conditions, Baby Java Pacitan orange peel produced D-limonene of 130.5 mg/g dry biomass, which was 2.8 times higher than Keprok Batu 55 orange peel. Meanwhile, the TPC for Baby Java Pacitan orange peel and Keprok Batu 55 orange peel were 46.1 mgGAE/g dry biomass and 43.9 mgGAE/g dry biomass, respectively.

Extraction of manganese from Indonesian manganese ore using sugarcane bagasse-acid reductive leaching

Widi Astuti — 2024-12-31

In this study, sugarcane bagasse was used as a reducing agent in manganese leaching from manganese ore from Way Kanan, Lampung under acidic conditions using sulfuric acid as a leaching reagent. Bagasse is an agricultural waste from the cane sugar manufacturing industry which is commonly found in Lampung Province. This agricultural waste has the potential to become a reducing agent in manganese leaching because it contains carbon in the form of cellulose and sugar. The optimization of the leaching conditions has been investigated with the parameters of H₂SO₄ concentration, temperature, and pulp density. The highest manganese leaching recovery was obtained under the following optimized conditions: 1 M H₂SO₄ concentration, 14 g sugarcane bagasse/20 g MnO₂, 50 g/L pulp density, 80 °C leaching temperature, 200 rpm stirring rate, and 4 hours of reaction time. The present process therefore deals with achieving the effective recovery of value-added products from low-grade manganese ore using agriculture waste as reducing agent.