Jurnal Rekayasa Proses

Karakterisasi biodegradable foam dari tepung tapioka dan ampas teh

Meliana Puji Astuti — 2024-07-01

Biodegradable foam atau yang disingkat dengan biofoam merupakan kemasan bioplastik yang terbuat dari bahan alami sebagai alternatif pengganti styroform yang lebih ramah lingkungan. Pembuatan biodegradable foam merupakan salah satu upaya untuk mengurangi sampah plastik di Indonesia. Selain itu, pembuatan biodegradable foam untuk menggantikan styrofoam yang bersifat karsinogenik karena adanya zat kimia yaitu styrene. Penelitian ini bertujuan untuk mengetahui karakteristik biodegradable foam dari tepung tapioka dan serat ampas teh. Metode pembuatan biodegradable foam pada penelitian ini yaitu baking process. Biodegradable foam dibuat dengan rasio pati:selulosa sebesar 12,5:10,5 gram dan 20,5:2,5 gram yang akan dicetak dengan oven dengan suhu operasi 80°C dan 130°C serta waktu operasi (pengovenan) 30 menit dan 60 menit. Biodegradable foam diuji sifat fisik dan mekanik. Kondisi optimum yang dihasilkan pada biodegradable foam pada penelitian ini yaitu pada suhu pemasakan 130°C selama 30 menit dengan nilai daya serap 28,54%, nilai kuat tarik 0,79 Mpa serta sifat biodegradasi dengan nilai sebesar 8,99% selama 14 hari.

Kajian kuat tekan dan kuat lentur material rammed earth dengan penambahan serat tandan kosong kelapa sawit sebagai dinding bangunan

Kinanti Wijaya — 2024-07-01

Rammed earth material buatan manusia yang setara dengan batuan sedimen. Proses dalam membangun rammed earth melibatkan campuran tanah, air, dan aditif, kemudian dipadatkan di dalam bekesting sampai keadaan yang sangat padat. Sejauh ini serat tandan kosong kelapa sawit hanya digunakan sebagai pupuk dan bottom ash dari hasil pembakaran yang ditumpuk sehingga dapat menimbulkan pencemaran lingkungan. Pada penelitian ini digunakan limbah serat tandan kosong kelapa sawit sebagai bahan subtitusi semen pada campuran rammed earth. Tujuan penelitian ini adalah untuk mengetahui pengaruh penambahan serat tandan kosong kelapa sawit terhadap nilai kuat tekan dan kuat lentur rammed earth. Metode penelitian yang dilakukan menggunakan kajian eksperimen. Variasi persentase penambahan serat tandan kososng kelapa sawit (TKKS) 0%; 0,75%; 1%; dan 1,25% terhadap berat semen. Benda uji dibuat dengan bentuk silinder ukuran diameter 15 cm dan tinggi 30 cm dan balok ukuran 60 cm x 15 cm x 15 cm. Umur perawatan benda uji selama 28 hari. Serat tandan kosong kelapa sawit yang digunakan pada penelitian ini memiliki panjang berkisar antara 1-5 cm. Parameter pengujian yaitu analisa saringan, kuat tekan dan kuat lentur rammed earth. Hasil penelitian menunjukkan bahwan kuat tekan optimum terjadi pada variasi TRES0 (0% serat TKKS) yaitu didapat nilai tekan rata-rata sebesar 5,06 MPa. Sedangkan kuat lentur optimum terjadi pada variasi LRES1.25 (1,25% serat TKKS) yaitu didapat nilai lentur rata-rata sebesar 0,98 MPa dimana mampu menahan beban rerata sebesar 7,3 kN.

Dekomposisi termal mangan oksalat (MnC2O4) dari ekstraksi mangan dari bijih mangan Lampung menghasilkan mangan oksida

Nurul Istiqomah Nainggolan — 2024-07-01

Research on the thermal decomposition of manganese oxalate (MnC₂O₄) from manganese extraction product of Lampung manganeses ore on manganese oxide recovery has been carried out. This study consisted of three main stages, namely reductive leaching, precipitation of manganese using oxalic acid to produce manganese oxalate, and thermal decomposition to produce manganese oxide. In the thermal decomposition process, MnC₂O₄as much 1 g and 3 g using decomposition time of 30 minutes, 1, 2, and 3 hours; and the temperatures of 350, 450, 550, and 650^oC. Purity of manganese oxide from thermal decomposition is 96%. XRD analysis show a that at a mass of 1 g using a temperature of 350 dan 450 ^oC with variations time, manganese oxides phase is obtained hausmannite (Mn₃O₄) and bixbyite (Mn₂O₃). But at temperatures of 550 and 650 ^oC the hausmannite phase compound is completely transformed into bixbyite phase with highest peak intensity at an angle of 2θ = 33^o. While using a mass of 3 g with all variations of time and temperature showed the acquisition of two types of manganese oxide phase, namely hausmannite and bixbyite.

Pengaruh konsentrasi mikroorganisme lokal pada fermentasi biji kopi arabika menggunakan fermentor skala pilot plant

Tri Hariyadi — 2024-07-01

Kopi wine adalah kopi hasil fermentasi yang memiliki rasa seduhan kopi yang khas menyerupai aroma dan rasa wine. Aroma dan rasa wine pada kopi wine dihasilkan oleh adanya perombakan senyawa pektin dan gula akibat metabolisme mikroorganisme selama proses fermentasi. Fermentasi biji kopi Arabika dilakukan dengan metode fermentasi basah, semi anarerob dalam reaktor sederhana menggunakan Mikroorganisme Lokal (MOL) tapai singkong. dengan waktu fermentasi 54 jam. Tujuan penelitian ini adalah mempelajari pengaruh suhu operasi terhadap perubahan kadar kafein , kadar etanol dan nilai pH biji kopi Arabika hasil fermentasi. Data hasil penelitian diolah menggunakan metode Anova Two-Factor Without Replications, dengan taraf signifikansi P < 5%. Penelitian ini menunjukkan bahwa suhu operasi berpengaruh signifikan terhadap kadar kafein dan etanol tetapi tidak berpengaruh signifikan terhadap nilai pH. Pengupasan berpengaruh signifikan terhadap kadar kafein, nilai pH, dan kadar etanol biji kopi Arabika hasil fermentasi. Biji kopi Arabika hasil fermentasi mengalami penurunan kadar kafein yaitu 86,4%, kenaikan kadar etanol 2,5 kali lebih tinggi dan kenaikan nilai pH dari 4,34 menjadi 5,33 pada suhu fermentasi 30°C. Fermentor skala pilot plant dibandingkan dengan fermentor skala lab memberikan pengaruh yang sama pada proses fermentasi kopi Arabika

Auditing approach at the finish mill to reduce energy consumption in cement production in indonesia

Herliati Rahman — 2024-07-01

Cement plants are substantial consumers of both thermal and electrical energy, with these energy expenditures accounting for over 40% of the overall production cost. A pivotal factor in this energy-intensive process is the clinker finish mill, a cornerstone of the cement industry. This study, therefore, centered its focus on a detailed examination of the performance of a tube-type finish mill equipped with two chambers and steel balls as the grinding medium. The methodology employed in this investigation included a comprehensive longitudinal test involving a series of meticulous steps to gauge and optimize the mill's performance. These steps encompassed steel ball sampling, the measurement of material levels within the mill, filling degree assessment, and sampling at one-meter intervals along the mill, with each sample weighing approximately 1 to 2 kilograms. This meticulous approach involved sampling during a period when the mill was operating steadily for at least 8 hours before a controlled shutdown, known as a "crash stop." The subsequent evaluation of the tube mill's performance extended to both its operation during the steady run and the crash stop. The findings stemming from this thorough audit are nothing short of remarkable. It is clear that the systematic evaluation conducted in this study led to a substantial enhancement in the production capacity of the finish mill, boasting an impressive 13.24% increase. Furthermore, the study also recorded a significant reduction in specific power consumption, effectively decreasing it by 3%. These outcomes not only underscore the vital importance of regular audits in cement grinding operations but also demonstrate the tangible benefits in terms of both increased production capacity and improved energy efficiency. Such improvements are not only pivotal for cost reduction but also contribute to the sustainability and competitiveness of cement production in an increasingly energy-conscious and cost-competitive industrial landscape

Batch filtration model of proanthocyanidins purification process from sorghum pericarp extract using polyethersulfone membrane

Moh. Azhar Afandy — 2024-07-01

Sorghum is one type of plant rich in polyphenol chemicals, one of which is proanthocyanidin. The goal of this work was to construct a filtration equation model for the purification of proanthocyanidin compounds in sorghum pericarp extracts utilizing ultrafiltration methods at varied transmembrane pressures and molecular weight cut-off values on asymmetric polyethersulfone (PES) membranes. The pressure difference and size of MWCO were used to determine the rate of cake formation induced by fouling and concentration polarization. The model suggested in this work is based on a compressible filtration model that can represent the decrease in permeability values and the cake formation process produced by the compression of particles deposited on the surface of the membrane. The results reveal that the transmembrane pressure and MWCO considerably affect the performance of the proanthocyanidins separation process employing ultrafiltration membrane technology. The higher the transmembrane pressure, the higher the permeation flow rate. The effect of MWCO on permeability varies with the type of membrane and fluid employed. The larger the MWCO, the higher the permeability since the membrane pores are more significant and more accessible for the liquid to pass through. The high transmembrane pressure not only helps the feed flow swiftly through the membrane and overcomes the resistance but also encourages substance accumulation until the bulge component drops, resulting in a blocking mechanism in the surface or pore of the membrane. The batch filtration model suggested in this work exhibits a reasonably good fit, which can be seen from the projected data values using a model that tends to approach the experimental data values and may be employed as a model that depicts the cake-forming process on the membrane surface.

Pengaruh parameter operasi terhadap persentase rekoveri litium dari sea water reverse osmosis (SWRO)

Ferian Anggara — 2024-01-17

Konsentrasi litium dalam sea water reverse osmosis (SWRO) terhitung masih kecil dibandingkan dengan sumber konvensional. Tren penggunaan air laut di dunia diperkirakan naik untuk tahun-tahun mendatang. Tujuan dari penelitian ini adalah untuk mengekstrak litium dari limbah cair SWRO. Bahan yang digunakan adalah limbah cair SWRO yang berasal dari PT. Cirebon Electric Power. Tahap awal yang perlu dilakukan adalah proses evaporasi. Proses evaporasi dilakukan pada temperatur 90°C. Proses evaporasi bertujuan untuk memekatkan atau mengkonsentrasikan mineral tertentu. Pada tahapan ini persentase penguapan divariasikan (70, 80, dan 90%). Proses presipitasi dilakukan dengan menggunakan bantuan natrium karbonat (Na₂CO₃). Tahap awal adalah pembuatan larutan Na₂CO₃ 3 Molar. 250 mL larutan hasil evaporasi disiapkan dan dipanaskan pada berbagai variasi temperatur (70, 80, dan 90 °C). Analisa tersebut juga menunjukkan kecenderungan semakin meningkatnya persentase rekoveri yang sejalan dengan meningkatnya persentase penguapan. Meskipun dampaknya kecil, temperatur presipitasi juga memberikan dampak dalam proses persentase rekoveri litium. Kondisi terbaik di dalam penelitian ini adalah pada persentase penguapan 90% dengan temperatur presipitasi 90 °C dengan persentase rekoveri mencapai lebih dari 70%.

The effect of NaOH concentration on silica leaching process from rice husk ash in South Sulawesi Province, Indonesia

Herlina Rahim — 2024-01-17

The issue of waste and raw material sources has become common in the processing industry. The ideal solution is to use waste as a substitute for primary material. The processing of rice husk waste for silica extraction can aid in resolving the issue of solid waste accumulation in the agricultural industry. The extraction process begins with burning and ashing the husk waste to increase the silica content. At 750 ^oC, the silica content increased to 88.06%. The leaching process was carried out to dissolve Si, and observe the behavior of other major elements, such as K, Ca, and P, from rice husk ash. Leaching was carried out in a 3-neck flask with external heating. The effect of the concentration of NaOH solution on elements recovery was studied in this experiment. The highest recovery of Si, K, Ca, and P reached 89.94%, 89.04%, 61.37%, and 78.61%, respectively, at 3 N NaOH concentration, 120 minutes, 300 rpm, and 10% S/L ratio. There was also a precipitate of Na₃PO₄ formed in the product solution after being left for 24 hours. This provides insight into the decantation process before precipitation using Al(OH)₃ in zeolite production.

Effect of NaBH4 Concentration and Addition of Sodium Dodecyl Sulfate (SDS) Surfactant in the Synthesis of Silver Nanoparticles as an Antibacterial Material

Arif Budianto Cuaca — 2024-07-01

This study was carried out to study the synthesis of silver nanoparticles in which the concentrations of the reducing agent NaBH₄ and SDS surfactant varied. Furthermore, the silver nanoparticles formed were characterized and tested for their antibacterial capabilities to show how varying parameters could influence the properties of silver nanoparticles as an antibacterial material. 0.05 M AgNO₃ precursor solution was mixed with NaBH₄ solution as a reducing agent in the 0.001–0.015 M concentration range. In addition, surfactant was also added under CMC conditions. The Ag⁺ ion reduction process took place at room temperature for 5 minutes. Then, the colloidal silver nanoparticle samples were characterized and tested for antibacterial properties. The bacteria used are Escherichia coli and Staphylococcus aureus. This study reduced 98% of Ag⁺ ions to Ag^o particles when using surfactants and the highest concentration of NaBH₄, whereas the synthesis of silver nanoparticles without surfactants could only reduce 88% of Ag⁺ ions. Using surfactants also produces particles with a much smaller diameter, around 51 nm. Antimicrobial testing also showed that silver nanoparticles with surfactants could inhibit bacterial growth. Thus, using surfactants and high concentrations of NaBH₄ can provide better antimicrobial characteristics and capabilities to these silver nanoparticles.

An extensive analysis and examination of techniques to enhance the efficiency of water extraction from wastewater generated during the recycling of nickel manganese cobalt (NMC) batteries using reverse osmosis membrane technology.

Agus Prasetya — 2024-07-01

Industrial water consumption will account for 22% of global water demand by 2030. Industry water conservation is encouraged by rapid corporate growth. Industrial resource usage and pollutant emissions can be reduced via cleaner production methods. Recycling is essential to greener production and the circular economy. Recycling is crucial to achieving the 2030 Sustainable Development Goals. The electric vehicle (EV) sector has propelled battery business growth in recent years, especially in Indonesia. The electric vehicle (EV) sector will benefit from using Nickel Manganese Cobalt (NMC) batteries. The study will use reverse osmosis (RO) membrane filtration to recover water from recovered NMC battery effluent. The experiment will investigate feed solution concentrations, pressures (8, 10, and 12 bar), and temperatures (30, 40, and 50°C). Two factors—permeate flux and metal ion rejection—determine reverse osmosis membrane efficiency. Li and Na metal rejection was maximum at 30°C and 12 bar, with 94-96% and 90-93% rejection rates, respectively. Under certain operating conditions, reverse osmosis membrane technology significantly reduced sodium (Na) concentration in NMC battery recycling effluent. Thus, wastewater is no longer saline. Reverse osmosis water can be reused for cooling due to its Li and Na concentrations.