Jurnal Teknik Kimia USU

Pengaruh Perlakuan Awal terhadap Karakteristik Bioetanol dari Limbah Kulit Singkong Karet (Manihot glaziovii)

2023-08-03T13:42:44+07:00

Rubber cassava peel waste (Manihot glaziovii) has a high carbohydrate content, so it is feasible to convert it into bioethanol. In general, bioethanol production consists of four steps, pretreatment, hydrolysis, fermentation, and purification. The purpose of this study was to determine the suitable treatment for obtaining bioethanol with the finest characteristics from rubber cassava peel using three treatment variations, the pretreatment process with variations in the dissolving ratio of sodium hydroxide (NaOH) 0.5 M of 1:10; 1:12.5; and 1:15 (w/v), the hydrolysis process with various concentrations of sulfuric acid (H₂SO₄) of 0.15 N; 0.30 N; and 0.45 N, and the fermentation process with variations in the fermentation time for 3 days, 7 days, and 9 days. Based on the research results, the highest glucose content was 0.91%, with variations in dissolving NaOH 0.5 M 1:15 (w/v) in the pretreatment process and variations in the concentration of 0.30 N H₂SO₄ in the hydrolysis process, while the highest ethanol content was 68.05% at a fermentation time of 7 days.

Aplikasi Edible Coating dari Limbah Kulit Udang dengan Aditif Asap Cair untuk Kemasan Sosis Sapi Antibakteri Ramah Lingkungan

2024-01-29T11:50:00+07:00

Edible coating is a food preservation technique by coating using antimicrobial substances which can inhibit the growth of bacteria. This research aims to develop an edible coating from shrimp shell waste with liquid smoke additives as antibacterial packaging for processing beef sausages. Chitosan is made in three stages, namely demineralization, deproteination and deacetylation. Beef sausages coated with edible coating were tested using organoleptic and antibacterial tests. The results of this research showed that the highest degree of deacetylation of chitosan was found in the variable concentration of sodium hydroxide (NaOH) 55% with a degree of deacetylation value of 93.59%. The water and protein content in beef sausages coated with edible coating with liquid smoke showed values of 52.45% and 12.65% on the 7th day. This is in accordance with the Indonesian National Standards (SNI). Coating beef sausages using edible coating from 2% chitosan with 8% liquid smoke solvent has antimicrobial properties because in the antibacterial test a clear zone appeared on the beef sausages coated with edible coating.

Karakterisasi Biofilm Selulosa Bakteri dengan Modifikasi Gliserol secara Ex Situ

2023-10-11T13:24:51+07:00

Bacterial cellulose (BC) is biomaterial from bacterial fermentation that contain high purity of cellulose, but 90% of BC pellicles retained water from the fermentation process. In this study, BC was modified with glycerol immersion in different concentrations (0%; 2,5%; 5%; 7,5%; 10%). For wide application, water content on BC must be removed by drying. Various oven drying condition are temperature 80 °C and 120 °C and time 60 minutes. The physical and mechanical properties of the dried BC biofilm were determined including tensile strength and elasticity. BC biofilm bound was identified by FTIR and EDX. The results showed that glycerol concentration was able to increase biofilm elasticity from 3.46% to 27.743%. However, glycerol immersion above 7.5% caused a decrease in the tensile strength of BC biofilm. The drying variation of 120 °C produces the highest tensile strength of 7.161 MPa when soaked in 7.5% glycerol. The drying variation of 80 °C produced a biofilm with the best elasticity of 27.473%. The results of FTIR and EDX analysis confirmed that there were differences in the contents of the modified BC.

Pengolahan Pati Rumbia menjadi Serbuk Glukosa secara Hidrolisis Enzimatis dengan Variasi Perbandingan Pati dan Air, Suhu Evaporasi, dan Suhu Pengeringan

2023-08-24T14:31:18+07:00

Glucose is a simple sugar that can be used as an sucrose alternative. Rumbia starch is rich in carbohydrates and abundant in Indonesia, potentially being used as a raw material for the production of glucose powder. The process involves starch hydrolysis, evaporation, and drying. The purpose of this study was to obtain optimal conditions of reducing sugar content, evaporation, and drying temperature based on variations in starch and water ratio (1:3, 1:4, 1:5, and 1:6), evaporation temperature (100 °C and 115 °C), and drying temperature (50 °C, and 70 °C). From this study, the optimal ratio of starch and water was 1:4 with a reduced sugar content of 99,77%. The optimal evaporation temperature was 115 °C, the brix content obtained is 85%, and the optimal drying temperature was 70°C, the water content obtained is 3,60%. Based on SNI of glucose, the glucose powder products meet the standard for water content and ash content. However, only in the ratio of starch and water 1:4 and 1:5, the reducing sugar content met the SNI of glucose.

Studi Pengaruh Variasi Konsentrasi Garam Dapur (NaCl) sebagai Larutan Elektrolit dan pH Bahan Baku dalam Pembuatan Biobaterai Kering Berbasis Limbah Kulit Pisang Kepok

2023-03-28T12:18:46+07:00

Batteries are single-use energy. Battery waste disposed on the ground will produce waste that is difficult to decompose naturally. Batteries contain chemicals that are toxic to soil fertility, such as potassium and sodium. One way to utilize battery waste is to turn it into bio-batteries. This research aims to minimize the waste of batteries and kepok banana peels that are underutilized by making environmentally friendly bio-batteries. This study also determines the voltage, current, and power of kepok banana skin-based bio-batteries. The method used is to conduct biobattery trials using paste from kepok banana peels. The results showed that kepok banana peels could conduct electricity to be used as a paste for bio-battery. The most significant voltage generated is 1.38 volts, while the largest current generated is 0.95 A. This bio-battery can last an average of 3 days 8 hours or 92.5 hours.

Pengaruh Kenaikan Laju Alir Fluida Panas dan Arah Aliran terhadap Kinerja Plate and Frame Heat Exchanger

2023-12-06T08:34:03+07:00

Plate and Frame Heat Exchanger (PFHE) is a plate and frame type heat exchanger that is efficient and effective in improving energy efficiency. Research using PFHE aims to determine the effect of increasing the flow rate of hot fluid on heat exchanger performance. This research was conducted at a flow rate variation of 0.7 L/min, 0.9 L/min, 1.1 L/min, 1.3 L/min, 1.5 L/min, 1.7 L/min, and 1.8 L/min with 180 seconds of testing each variation and recording data every 2 seconds. The cold fluid used is tap water and the hot fluid used is distilled water. The results showed that with the increase in hot fluid flow rate, the performance of PFHE also increased because the effectiveness of NTU (Ɛ-NTU) increased. The Ɛ-NTU value of unidirectional flow is 25.37% - 44.87% and in the opposite direction 37% - 68.39%. The largest Ɛ-NTU value in the countercurrent flow indicates that the countercurrent flow is more effective than the unidirectional flow. In addition, increasing the flow rate increases the Reynold's number (Nre) and Nusselt's number (Nu) which indicates the greatest convection heat transfer occurs at the highest flow rate.

Pengaruh Jenis Cairan, Jenis Batang, dan Panjang Batang pada Penentuan Distribusi Ukuran Partikel Bubuk Kaca Menggunakan Buoyancy Weighing-Bar Method (BWM)

2024-02-26T11:49:33+07:00

Particle size distribution is one of the important physical parameters in industry. A new method has been developed, the buoyancy weighing-bar method to determine the particle size distribution. This study examines the application of the buoyancy weighing-bar method for the determination of the particle size distribution of glass powder. Measurements were made by varying the type of liquid, the type of rod, and the size of the rod length. From this study, it was obtained that the best condition in determining the particle size distribution of glass powder is using aluminum rods with a length of 210 mm in 96% ethanol. The results of determining the particle size distribution of glass powder by using the buoyancy weighing-bar method at the best conditions are comparable to the results of determining the particle size distribution obtained using the settling balance method.

Analisis Pengaruh Penambahan Magnesium Oksida terhadap Sifat Mekanis Bioadhesif Berbasis Kitosan-Karagenan

2023-12-27T09:18:28+07:00

This study investigates the effect of magnesium oxide (MgO) as a filler in enhancing the bioadhesive properties of chitosan and carrageenan-based adhesives. The primary focus is on improving tensile strength, viscosity, solid content, and thermal properties. The results indicate that the addition of 0.75% w/v MgO significantly increased tensile strength from 9.76 kPa to 21.76 kPa and viscosity from 34.26 cP to 617 cP with a 0.5% w/v MgO addition. The solid content also increased from 9.81% to 13.19% with increased MgO concentration. The addition of benzoyl peroxide (BPO) reduced curing time, enhancing process efficiency. Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy confirmed improvements in structural and chemical stability, while Differential Scanning Calorimetry showed better curing efficiency. This study suggests MgO as a potential filler to improve mechanical properties and adhesion of bioadhesives, relevant for medical applications.

Karakteristik Sifat Fisik Membran Elektrolit Polimer Berbasis Kitosan Larva Black Soldier Fly/Polivinil Alkohol/Poliakrilonitril dengan Penambahan Ammonium Klorida

2024-02-06T12:37:03+07:00

Black soldier fly larvae shells/BSF-based chitosan can be utilized as polymer electrolyte membrane. This research aims to analyze the physical characteristics of BSF chitosan/PVA/PAN/NH₄Cl by varying amount of chitosan and ratio of PVA: PAN. Membrane was fabricated using the phase inversion method. Polymer electrolyte with a mixture of 1.20 g of PVA/PAN with ratio variations of 10:90 and 20:80 and chitosan variations of 2.4 g; 2.8 g; and 3.2 g. Chitosan was also FTIR-characterized. Density and wáter absorption of polymer electrolyte with chitosan composition of 2.4 g; 2.8 g; 3.2 g and PVA/PAN ratio of 10:90 were 0.824 g/mL; 1 g/mL and 1.51 g/mL and water absorption 28.571%; 38.333%; and 46.154%, respectively; and at PVA/PAN ratio of 20:80 were 0.734 g/mL; 1.03 g/mL and 1.096 g/mL and water absorption 62.5%; 66.667% dan 100%, respectively. Best physical property was obtained with the incorporation of 2.4 g of chitosan and 10:90 PVA/PAN ratio.