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Efek Pretreatment Ultrasonikasi Terhadap Hidrolisis Enzimatis Spirulina platensis Residue
Get PDFThe development of renewable energy from microalgae sources is still being studied to overcome the world energy crisis, one of which is biodiesel from Spirulina platensis. However, the extraction process from Spirulina platensis to obtain oil leaving waste called Spirulina platensis residue (SPR). SPR still contains carbohydrates in the form of cellulose in cell walls and starch in plastids. Carbohydrates can be converted into bioethanol through the hydrolysis process. To optimize the enzymatic hydrolysis of carbohydrates, pretreatment is needed to break down the cell walls. One method of pretreatment is ultrasonication. This study aimed to determine the effect of ultrasonication pretreatment on enzymatic hydrolysis. Ultrasonication was carried out with time variations (15, 30, and 45 minutes) then continued hydrolysis at 40 oC for 8 hours using α-amylase and glucosidase (1: 1) enzymes. The results of hydrolysis in the form of reducing sugars were analyzed using the Nelson Somogyi method and obtained an optimal pretreatment time is 30 minutes with a reducing sugar concentration of 2.493,3 mg/LPengembangan energi terbarukan dari sumber mikroalga masih terus dikaji untuk mengatasi krisis energi dunia, salah satunya adalah biodiesel dari Spirulina platensis. Namun, proses pengepresan minyak dari Spirulina platensis menyisakan limbah yang disebut Spirulina platensis residue (SPR). SPR masih mengandung banyak karbohidrat dalam bentuk selulosa di dinding sel dan pati di dalam plastid. Karbohidrat dapat dimanfaatkan menjadi bioetanol melalui proses hidrolisis. Untuk mengoptimalkan hirolisis enzimatis terhadap karbohidrat maka diperlukan pretreatment dengan tujuan memecah dinding sel. Salah satu metode pretreatment adalah ultrasonikasi. Penelitian ini bertujuan untuk mengetahui pengaruh pretreatment ultrasonikasi terhadap hidrolisis enzimatis. Ultrasonikasi dilakukan dengan variasi waktu (15, 30, dan 45 menit) kemudian dilanjutkan hidrolisis pada suhu 40 oC selama 8 jam menggunakan enzim α-amilase dan glukosidase (1:1). Hasil hidrolisis berupa gula reduksi dianalisis menggunakan metode Nelson Somogyi dan diperoleh waktu pretreatment optimal selama 30 menit dengan konsentrasi gula reduksi sebesar 2.493,3 mg/L
Production of briquettes from Indonesia agricultural biomass waste by using pyrolysis process and comparing the characteristics
Get PDFIndonesia biomass waste is a potential feedstock as a source of renewable energy since it can be converted into carcoal briquettes. However, the production of the briquettes using pyrolysis process using the agricultural waste was lacking. In this research, briquette was made from palm shells, corncob and soybean stem wood due to its high availability and have high cellulose content. The purpose of this research was to produce briquettes from three kind of raw materials by employing pyrolysis process and compared the characteristics. The briquette was made from different type of raw materials (palm shells, corncob and soybean stem) and the concentration of binder : 3-7 %. Pyrolysis was done at 500 °C, and 100 kg / cm2 of pressing pressure. Results showed that, the best charcoal briquette was achieved from palm shells by using 5% binder, which resulted 4,1% moisture content, 3.4% ash content, 15% volatile matter content, 77.5% carbon content, 7075 cal/g calorific value and 1.4 kg/cm2 compresive strength. It is found that the concentration of binder and raw material influenced the quality of the briquettes. In overall, the production of the briquettes by employing pyrolysis method could meet the standard
Effect of particle sizes and sodium hydroxide concentrations on silica extraction from minerals obtained in Kalirejo village, Kokap, Kulonprogo, Yogyakarta
No full textSilica is mainly used in the production of rubber, glass, cement, glass, ceramics, paper, cosmetics, electronics, paintings, healthcare and other industries. Kalirejo village has a potential abundant resource of silica minerals. However, to refine it, high cost of extraction should be done to obtain high purity of silica. Different refining methods influence different purity of the silica. The purpose of this research was to study the refining process of mineral rock silica from Kalirejo village, Kokap, Kulonprogo by emplying simple and cheap solid-liquid extraction. Extraction was done by varying the particle size at 100 - 200 mesh, while NaOH concentration was varied in 0.5 N to 5 N. Results showed that minerals taken from Kalirejo village was dominated by silica (23%). The largest extract (4.89 gram) was obtained at 200 mesh and using NaOH 5 N with yield of 15.07%. Higher NaOH and higher particle size enhanced the extraction yield. This finding could help small communities in Kalirejo village to enhance the quality of silica by employing simple and cheap extraction process
PENGARUH PERTAMBANGAN PASIR TERHADAP EROSI DAN SEDIMENTASI SUNGAI (STUDI KASUS DI DESA TANJUNG ALAM KECAMATAN SEI DADAP KABUPATEN ASAHAN)
Get PDFSand mining in Tanjung Alam Village, Sei Dadap District, Asahan Regency, which is carried out with a suction machine is thought to have a negative impact on the environment. This study aims to examine the effect of sand mining on erosion and sedimentation in that river. The analysis steps begins with measuring the river profile, measuring flow velocity, measuring river discharge, measuring sediment concentration, measuring rainfall, measuring slope and calculating the estimated rate of erosion. To calculate the estimated erosion rate in this study using the USLE method and to calculate the sediment load using SNI 3414: 2008 with the depth-integrating technique. Based on the calculation results, it is known that sand mining activity causes narrowing of the river profile, accelerates river flow, increases river discharge so that it increases the rate of erosion, and sedimentation. The highest sediment load value is at point 5 which is located downstream of mining 1 and 2 with a value of 2922.48 tons/day. While the highest estimated erosion rate is at point 5 with a value of 125.9 tons/ha/year which is included in the heavy category. Measurements at each sampling point prove that sand mining activities have a high impact on increasing the rate of erosion and sedimentation in rivers.Sand mining in Tanjung Alam Village, Sei Dadap District, Asahan Regency, which is carried out with a suction machine is thought to have a negative impact on the environment. This study aims to examine the effect of sand mining on erosion and sedimentation in that riverThe analysis steps begins with measuring the river profile, measuring flow velocity, measuring river discharge, measuring sediment concentration, measuring rainfall, measuring slope and calculating the estimated rate of erosion. To calculate the estimated erosion rate in this study using the USLE method and to calculate the sediment load using SNI 3414: 2008 with the depth-integrating techniqueBased on the calculation results, it is known that sand mining activity causes narrowing of the river profile, accelerates river flow, increases river discharge so that it increases the rate of erosion, and sedimentation. The highest sediment load value is at point 5 which is located downstream of mining 1 and 2 with a value of 2922.48 tons/day. While the highest estimated erosion rate is at point 5 with a value of 125.9 tons/ha/year which is included in the heavy category. Measurements at each sampling point prove that sand mining activities have a high impact on increasing the rate of erosion and sedimentation in river
Kinetic Study on Coagulation Process with Poly Aluminium Chloride and Alum Coagulants in Treating The Liquid Waste of Tempeh Industry
Get PDFSeveral factors that influence the coagulation process in reducing chemical oxygen demand (COD) in wastewater are processing time, coagulant dose and type of coagulant. The effect of these three factors on the reduction of COD in tempeh industrial wastewater during the coagulation process has been investigated by Hidayah (2018). However, kinetic studies in depth have not been done by Hidayah (2018). Therefore, the aim of this study was to develop a new kinetic model that can predict the performance of the coagulation process. It is hoped that the kinetic model can be used in a wider range of operating conditions. In this study, the pseudo first order and pseudo second order kinetic models were tested to get the best model. Based on simulation results, both models produced almost the same accuracy. For reason of simplification, the pseudo first order model was chosen as the basic model in this study. Furthermore, modifications were made to the pseudo first order model so that the effect of processing time, coagulant dose and type of coagulant appeared in the model. This kinetic model was successfully tested to predict the coagulation performance of study of Hidayah (2018) with an average Mean Absolute Percentage Error (MAPE) of 10.8%
Uji Aktivitas Karbon Aktif Tongkol Jagung Terimpregnasi Fe2O3 sebagai Biosorben Limbah Warna Metilen Blue
Get PDFMethylene blue is one of dying waste that causes harmful effect both enviromental and public health risks. A method to overcome the problem is to adsorb it with the activated carbon. Apart from that, corn cob is potential biomass with can convert to activated carbon. The aim of this research is to syntethic and to modify corn cob activated carbon with iron oxide. It is expected to increase the afinity of methylene blue to the activated carbon surface. The modification is done by wet impregnation and the effectiveness of the impregnated corn cob activated carbon is studied by analyse the persen removal of methylene blue in every interval time. The result show that in the concentration range of Fe load impregnation between 1%-3% which has been used, the corn cob activated carbon with concentration of Fe load 2% has the most optimum ability in methylene blue adsorption with the adsorption capacity 44,9%. Moreover, the effect pH shows that in acidic condition the adsorption of methylen blue is better than in netral conditionSalah satu limbah warna yaitu metilen blue dapat memberikan dampak yang buruk terhadap lingkungan dan kesehatan. Salah satu upaya mengatasinya adalah dengan proses adsorpsi dengan karbon aktif. Biomasa yang potensial dikembangkan sebagai karbon aktif adalah tongkol jagung karena ketersediaanya yang melimpah. Tujuan dari penelitian ini adalah membuat karbon aktif dari tongkol jagung dan memodifikasi permukaanya dengan besi oksida (Fe2O3). Modifikasi ini dilakukan dengan tujuan karbon aktif terimpregnasi dapat memiliki daya tarik atau afinitas yang lebih baik terhadap metilen blue. Proses modifikasi dilakukan dengan wet impregnation method. Hasil dari karbon aktif terimpregnasi oksida besi (KAJ-Fe) kemudian diuji aktivitasnya terhadap metilen blue. Selain itu, pengaruh Ph pun ikut dipelajari dalam penelitian ini. Berdasarakan percobaan yang telah dilkukan terlihat bahwa pada range konsentrasi loading Fe yang digunakan (1-3%) menunjukkan bahwa Loading Fe dengan konsentrasi 2% memberikan hasil adsorpsi metilen blue yang paling optimal dimana kapasitas adsorpsinya sebesar 44.9%. Selain itu, pH asam pada metilen blue memberikan hasil adsorpsi yang lebih baik daripada Ph netral
Pretreatment Spirulina platensis Residue untuk Produksi Bioetanol
Get PDFPemerintah Indonesia berusaha untuk menggurangi penggunaan bahan bakar fosil dengan mendorong adanya transisi ke sumber energi terbarukan. Bioetanol merupakan salah satu alternatif energi terbarukan yang mampu mengurangi penggunaan bensin di sektor transportasi. Bioetanol dapat diproduksi dari spirulina platensis residu (SPR) yang masih mengandung karbohidrat yang tinggi. Untuk memaksimalkan perolehan bioethanol diperlukan proses pretreatment yang sesuai untuk memecah dinding sel SPR sehingga diperoleh glukosa yang siap difermentasi. Pada penelitian ini dilakukan tiga metode pretreatment yaitu ultrasonikasi, autoclave dan enzimatis. Pretreatment dengan ultrasonikasi dilakukan dengan ultasonicator batch 40 kHz selama 30 menit dan menghasilkan glukosa sebesar 147,1154 mg/L. Sedangkan dengan autoclave pada suhu 121 oC selama 30 menit menghasilkan glukosa sebesar 21.15385 mg/L. Pretreatmen enzimatis dilakukan dengan menggunakan kombinasi enzim α-amylase dan amyloglucosidase (1:0; 0,75: 0,25; 0,5:0,5; 0,25:0,75 dan 0:1) pada suhu 40 oC selama 180 menit. Yield glukosa maksimum diperoleh pada pengguanaan enzim α-amylase: amyloglucosidase = 0,25:0,75 yaitu sebesar 33,15%
Pengaruh Penambahan Antioksidan Simplisia Kunyit Terhadap Angka Peroksida Minyak Kacang Tanah
Get PDFPeanut oil is a peanut product that is used for the food industry. The high content of fatty acids in the form of oleic acid causes peanut oil to break down easily, so it is necessary to add antioxidants to inhibit the oxidation process.The natural antioxidant used is turmeric. The purpose of this study was to determine the effect of the addition of turmeric antioxidants on the peroxide rate of peanut oil. The research method for calculating the peroxide number uses iodometric titration. The results showed that the greater the concentration of turmeric simplicia added to peanut oil, the greater the antioxidant activity. The greatest antioxidant activity was obtained from the weight of simplicia 0.4 g with a long immersion period of 7 days, which resulted in a peanut oil peroxide value of 14.5 ml N / gr.Minyak kacang tanah merupakan produk olahan kacang tanah yang dipakai untuk keperluan industri pangan. Kandungan asam lemak berupa asam oleatnya yang tinggi menyebabkan minyak kacang tanah mudah rusak sehingga perlu ditambahkan antioksidan untuk menghambat proses oksidasi. Antioksidan alami yang digunakan adalah kunyit. Tujuan dari penelitian ini adalah mengetahui pengaruh penambahan antioksidan kunyit terhadap angka peroksida minyak kacang tanah. Metode penelitian perhitungan angka peroksida menggunakan titrasi iodometri. Hasil penelitian menunjukkan bahwa semakin besar konsentrasi simplisia kunyit yang ditambahkan pada minyak kacang tanah, maka aktivitas antioksidan semakin besar. Aktivitas antioksidan terbesar didapat dari berat simplia 0,4 gr dengan lama perendaman 7 hari menghasilkan angka peroksida minyak kacang tanah 14,5 ml N/gr
Potensi Spirulina platensis sebagai sumber kosmetik dan bioplastik (review)
Get PDFSpirulina plantesis is a cyanobacteria that has many purposes such as for cosmetics, and food industry. In addition, Spirulina platensis can accumulate polyhydroxybutyrate (PHB), a type of bioplastic. This review discussed the potency of Spirulina platensis as a source of bioplastics and cosmetics. From the review, Spirulina contained bioactive compound, C-phycocyanin, which can inhibit cell damage and is very potential to be applied for cosmetics. The PHB content in Spirulina tends to be small compared to other microalgae. To reduce the cost of PHB from Spirulina, the biorefinery concept can be applied, by recovery the bioactive components (C-phycocyanin), while the residue can be used as a source of PHB.Spirulina plantesis merupakan salah satu Jenis mikroalga yang mempunyai banyak kegunaan, beberapa di antaranya yaitu untuk pembuatan kosmetik. Di samping itu, Spirulina platensis merupakan cyanobacteria yang dapat mengakumulasi bioplastik jenis polihidroksibutirat (PHB). Review paper ini membahas tentang potensi produksi Spirulina platensis sebagai sumber bioplastik dan kosmetik. Dari pemaparan, Spirulina memiliki senyawa yang memiliki kandungan bioaktif C-phycocyanin yang dapat menghambat kerusakan sel dan sangat potensial diaplikasikan untuk kosmetik. Kandungan PHB yang ada di Spirulina cenderung kecil. Untuk menurunkan biaya produksi PHB, dapat dilakukan konsep biorefinery, dengan mengambil komponen bioaktif, sementara residunya dapat digunakan sebagai sumber PHB
Process Dynamic of Two-Thermal-Tank-Series with Dead Time
Get PDFThe multi-tank-series system could come up the problem of instability due to dead-time. The goals of this work are to study the dynamic behavior of Two-Thermal-Tanks-Series (TTTS) with dead time through the open loop experiment in laboratory, and to propose the new-module of fundamental chemical engineering practicum in field of process dynamic for undergraduate program. The two stirred-tank-heaters @10L were designed for heating of water fluid. Both of tanks were designed overflow to maintain their volume constant. The gate valve was installed in the inlet pipe of Tank-1 to adjust its volumetric flowrate (f). The inlet temperature of Tank-1 (T1), the liquid temperatures in Tank-1 (T2) and Tank-2 (T3) were measured by thermocouple multi-channels. The volt-ampere-regulators were used to adjust the electrical energy in Tank-1 (q1) and Tank-2 (q2). The mathematical model was solved and rigorously examined in Xcos/Scilab. In order to study the dynamic behavior of TTTS, the inlet flowrate disturbance was made based on step input change. According to our investigation in laboratory and open loop simulation, both Tank-1 and Tank-2 gave stable responses, the model’s responses showed the closed and similar trend with laboratory’s responses, and time delay of about 30 seconds has been found in Tank-2