cover
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kab. sleman,
Daerah istimewa yogyakarta
INDONESIA
Jurnal Rekayasa Proses
ISSN : -     EISSN : -     DOI : -
Core Subject :
Arjuna Subject : -
Articles 12 Documents
Search results for , issue "Vol 16, No 1 (2022)" : 12 Documents clear
Peruraian Anaerobik Termofilik Palm Oil Mill Effluent dengan Variasi Konsentrasi Substrat Roberty Wisnu Alvania Kartika; Nadiya Salsabila Desman; Irfan Dwidya Prijambada
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69574

Abstract

High utilization of palm oil in Indonesia corresponds to palm oil mill effluent (POME). The POME has chemical oxygen demand (COD) of up to 100.000 mg/L, which can pollute the ecosystem if not adequately treated. One of the methods to manage POME is anaerobic thermophilic digestion. The advantage of this method is the production of methane gas which is a form of alternative energy. Substrate concentration affects anaerobic digestion. This preliminary experiment aims to evaluate the performance of anaerobic thermophilic digestion on various POME concentrations at 55 °C. The anaerobic digestion was run with 16.000, 11.000 and 5.000 mg sCOD/L substrate concentrations. Digested cow manure (DCM) was used as inoculum. The process was running in a continuous system after 7-days of acclimatization of the batch system. The result shows that 16.000 and 11.000 mg sCOD/L concentrations produced more methane, but the methane yield was not statistically significant with the Tukey test (p=0,05). The POME with a 5.000 mg sCOD/L concentration produced less methane and plummeted after day 85. The lower methane production at lower substrate concentration was due to the low sCOD availability and high volatile fatty acid (VFA) accumulation which inhibited the methane production.
Teknoekonomi Penyingkiran Senyawa Sulfur dari Kondensat Gas Alam dengan Metode Desulfurisasi Oksidatif-Ekstraktif Tri Partono Adhi; Sardenianto Sardenianto; Antonius Indarto
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69864

Abstract

In the oil and gas production process, apart from hydrocarbons, a number of impurities are produced, including CO2 and sulfur in various concentrations, depending on the conditions and characteristics of the reservoir and the location where the oil and gas is located. To process sulfur removal from condensate, the common technology is HDS (Hydrodesulfurization). However, with process requirements such as high temperature, pressure, and intensive hydrogen consumption, an alternative technology is needed for this desulfurization. One of them is oxidative-extractive desulfurization. Technical and economic evaluations to determine the feasibility of applying on an industrial scale need to be studied further. The study of oxidative-extractive desulfurization process of sulfur compounds (represented as dibenzothiophene, DBT) was carried out using H2O2/formic acid as oxidizing agent and catalyst, as well as extraction with DMF. For a capacity of 1000 bpd of condensate with 1%-wt sulfur, desulfurization was successfully carried out with sulfur removal of 96.55% and condensate recovery of 99.41%. A processing fee of 9.14 USD/barrel is required, of which 84% is required for chemicals. The alternative process configuration for DMF recovery succeeded in reducing chemical costs by 35.5% and reducing total processing costs by 27.0% to 6.67 USD/barrel. In this alternative process configuration, 95.80% sulfur removal was achieved with condensate recovery of 99.21%.
Tertiary butylhydroquinone influence over oxidation stability of biodiesel from waste cooking oil Dwi Ardiana Setyawardhani; Thufeil 'Ammar; Yusuf Ammar
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.67177

Abstract

ABSTRACTAn oxidation stability is very important for a long-term storage of biodiesel. Some physical (density and viscosity) and chemical properties (acid value, iodine value, and peroxide value) were analyzed to predict the oxidation stability for biodiesel produced from Waste Cooking Oil (WCO). WCO is one of the potential feedstocks in Indonesia, which is a large cooking oil consumer. Biodiesel from WCO was produced by transesterification process in 60 oC temperature for one hour reaction time. Methanol was added in 4:1 (v/v) ratio of WCO with 2% potassium hydroxide as a catalyst. This study observed the influence of tertiary butylhydroquinone (TBHQ), a synthetic antioxidant, on  the oxidation stability of biodiesel. TBHQ was used as an antioxidant agent to prevent biodiesel oxidation for such long-term storage. It was blended with biodiesel at various concentrations (0-1200 ppm). Samples were taken every week to measure the density, viscosity, acid value, iodine value (IV) and peroxide value (PV) during the storage process of the biodiesel blends which was conducted for 4 weeks. The experimental results revealed that an improvement in oxidation stability was achieved in all TBHQ concentrations. All parameters meet Indonesia’s National Standards (SNI) for biodiesel added with TBHQ up to 1200 ppm. Biodiesel which was treated with 1200 ppm of TBHQ provided the best result, due to its density, viscosity, IV, and PV.  However, TBHQ addition was did not affect the free fatty acid and acid number for 4 weeks of storage.Keywords: antioxidant; biodiesel; oxidation stability; waste cooking oilABSTRAKKetahanan oksidasi merupakan karakteristik yang sangat penting dalam penyimpanan biodiesel. Penelitian ini menganalisis sifat-sifat fisis (densitas dan viskositas) serta sifat-sifat kimia (angka asam, angka iod dan angka peroksida) biodiesel minyak jelantah untuk memperkirakan ketahanannya terhadap pengaruh oksidasi. Minyak jelantah merupakan salah satu bahan baku biodiesel yang sangat potensial di Indonesia, karena kapasitas penggunaannya yang cukup besar. Biodiesel minyak jelantah dihasilkan dengan transesterifikasi pada suhu 60 oC selama 1 jam. Metanol yang ditambahkan dalam reaksi ini menggunakan perbandingan volume 4:1, dengan katalis KOH sebanyak 2% berat minyak. Penelitian ini mempelajari pengaruh tertiary butylhydroquinone (TBHQ) terhadap ketahanan oksidasi biodiesel minyak jelantah. TBHQ digunakan sebagai antioksidan dalam penyimpanan biodiesel jangka panjang. TBHQ dicampurkan ke dalam biodiesel dengan variasi konsentrasi 0-1200 ppm. Ketahanan oksidasi dipelajari selama masa simpan 4 minggu. Sampel dianalisis densitas, viskositas, angka asam, angka iod dan angka peroksida setiap minggu. Hasil analisis menunjukkan bahwa ketahanan oksidasi biodiesel minyak jelantah telah memenuhi SNI pada semua konsentrasi TBHQ. Hasil terbaik diberikan oleh biodiesel jelantah yang ditambahkan 1200 ppm TBHQ, menilik dari nilai densitas, viskositas, angka peroksida dan bilangan iod. Penambahan TBHQ tidak berpengaruh secara signifikan terhadap nilai asam lemak bebas dan angka asam selama penyimpanan 4 minggu.Kata kunci: biodiesel, ketahanan oksidasi, antioksidan, minyak jelantah
Efisiensi energi dan evaluasi keselamatan pada modifikasi penggantian katalis unit Desulfurizer di PT. Kaltim Methanol Industri (KMI), Bontang, Indonesia Dwi Agus Dermawan; Reno Imam Arthapersada; Muhammad Kurniawan Adiputra; Indra P Hakim; Imam Karfendi Putro; Rochim Bakti Cahyono
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.68759

Abstract

A B S T R A KMetanol sebagai salah satu bahan kimia dasar dapat digunakan secara langsung sebagai campuran bahan bakar untuk internal combustion engines atau bahan baku antara (intermediate chemicals) untuk memproduksi beragam bahan kimia penting seperti formaldehyde, asam asetat, dimethyl ether (DME), dan methyl tertiary butyl ether (MTBE). PT. KMI memproduksi metanol dengan bahan baku gas alam melalui proses steam reforming. Penelitian ini bertujuan untuk mendapatkan produk yang berkualitas dan proses produksi yang efisien, dibutuhkan metana yang terbebas dari pengotor sulfur. Untuk itu diperlukan unit desulfurizer berupa fixed bed berisi katalis CoMo pada unit 010-D03 dan adsorben penjerap sulfur pada unit 010-D01. Pada tahun 2019 telah dilakukan penggantian katalis 3 in 1 yang mampu menghilangkan sulfur dalam satu tangki fixed bed (010-D01). Berdasarkan data dari logbook operasi pabrik berupa pressure drop, flowrate, suhu, dan komposisi dilakukan evaluasi penghematan energi dan keselamatan dari modifikasi ini. Penggantian katalis baru pada tangki 010-D01 yang memungkinkan tangki CoMo dioperasikan dalam kondisi kosong sehingga mengurangi pressure drop di dalam sistem. Adanya penurunan pressure drop mengakibatkan konsumsi steam pada kompresor NG menjadi berkurang sehingga didapatkan penghematan energi sebesar 379 kg/jam yang setara dengan 40913 USD/tahun atau 8545 MMBtu/tahun. Untuk menjamin keselamatan dari modifikasi, dilakukan evaluasi terhadap potensi deflagration-detonation dan api menggunakan komponen segitiga api. Berdasarkan parameter keberadaan oksigen, diagram flammability, dan autoignition temperature, modifikasi yang mengoperasikan tangki 010-D03 dalam kondisi kosong, aman dari bahaya terbentuknya api dan ledakan. Dengan demikian, modifikasi penggantian katalis dan pengosongan tangki 010-D03 terkonfirmasi meningkatkan efisiensi energi dan menghemat pemakaian sumber daya alam, sehingga mendorong aplikasi nyata sustainable development di dunia industri. Kata kunci: CoMo katalis; energi kompresi; unit desulfurizer; pressure dropABSTRACT As one of the essential chemicals, methanol can be used directly as fuel mixer for internal combustion engines or intermediate chemicals which can be utilized to produce various final chemicals such as formaldehyde, acetate acid, dimethyl ether (DME), dan methyl tertiary butyl ether (MTBE). PT. KMI produces methanol based on natural gas through steam reforming process. The study aims to get good product quality and efficient process production, the raw material of methane should be avoided from any impurities, especially sulphur. To get those target, PT. KMI installed desulfurizer unit that consist of CoMo fixed bed catalyst on 010-D03 unit and adsorbent on 010-D01 unit. As improvement on 2019, the engineer found the 3 in 1 catalyst which success to preclude the sulphur trace element in the one vessel of 010-D01 unit. Based on the logbook data from plant operation such as pressure drop, flowrate, temperature and gas composition could be performed the evaluation to minimize the energy consumption and safety level of those modification. The replacement using new catalyst (3 in 1) on the 010-D01 unit allowed the system to operate the CoMo vessel (010-D03) with empty condition that could reduce pressure drop within the system. Based on the pressure drop reducing, the consumption of steam for running the NG compressor decreased and obtained the energy saving around 379 kg of steam/hour, which was equal to 40913 USD/year or 8545 MMBtu/year. In order to ensure the safety of this modification, the evaluation of fire and deflagration-detonation potential was done using triangle diagram. Based on the availability of oxygen, flammable region and autoignition temperature, the modification of 010-D01 unit which cause the empty operation of 010-D03 unit was safe from fire and explosion hazard. Therefore, the process modification through catalyst replacement could increase energy efficiency and natural resources saving for real action of sustainable development in the industrial sector. Keyword: CoMo catalyst; compression energy; desulfurizer unit; pressure drop
Peningkatan kualitas air buangan ke laut dengan metode FLOCOM untuk lapangan offshore produksi minyak dan gas bumi Adji Swandito; Herman Amrullah; Sutrisno Sutrisno; Dendy Andalas Putra; Cesaria Riza Asyifa
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69285

Abstract

A B S T R A C TWastewater disposal to the sea in oil and gas production is an important and critical part to ensure the continuity of production process and environment. Quality enhancement to reduce oil content in wastewater disposal to the sea could be achieved by injecting chemical in oil and water separation process. Chemical reverse demulsifier base flocculant is generally used for chemical treatment of wastewater disposal; however excessive injection of flocculant forms flock particle that causes deadlock on operation tools. The purpose of this research was to study the effect of innovative FLOCOM method application in wastewater to the sea quality. The experiment was conducted in offshore Attaka field that had flock problem. FLOCOM method application results showed reduction of oil content in wastewater to sea from 20 mg/L to 10 mg/L and reduction of chemical consumption in offshore Attaka field from 4.6 gallons per thousand barrel oil equivalent to 3.2 gallons per thousand barrel oil equivalent.Keywords: flocculant; FLOCOM method; offshore oil and gas field; reverse demulsifier; wastewater to seaA B S T R A KAir buangan ke laut dalam proses produksi minyak dan gas bumi merupakan hal yang penting dan krusial untuk menjamin kesinambungan proses produksi dan lingkungan. Peningkatan kualitas air buangan ke laut dalam rangka menurunkan jumlah minyak terkandung dalam air buangan dapat dilakukan dengan cara injeksi bahan kimia dalam proses pemisahan minyak dan air. Bahan kimia yang umumnya digunakan adalah reverse demulsifier berbasis flokulan. Namun penggunaan flokulan dalam jumlah banyak dapat menimbulkan permasalahan operasi dengan timbulnya partikel flock yang dapat menyebabkan kebuntuan pada alat operasi. Tujuan penelitian ini adalah mempelajari pengaruh aplikasi metode inovasi FLOCOM dalam kualitas air buangan ke laut. Penelitian dilakukan di lapangan offshore Attaka yang terdapat permasalahan flock. Hasil penelitian menunjukkan bahwa metode FLOCOM dapat menurunkan kandungan minyak dalam air buangan ke laut dari 20 mg/L menjadi 10 mg/L serta dapat menurunkan konsumsi injeksi bahan kimia pada lapangan offshore Attaka dari 4.6 gallons per thousand barrel oil equivalent menjadi 3.2 gallons per thousand barrel oil equivalent.Kata kunci: air buangan ke laut; flokulan; lapangan offshore minyak dan gas bumi; metode FLOCOM; reverse demulsifier
Adsorption study of mango peel activated carbon as iron removal for batik waste industry Agung Nugroho; Nur Layli Amanah; Revo Gilang Firdaus
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69404

Abstract

A B S T R A C TMango peel waste which has a carbon functional group was converted to activated carbon. The as-synthesized activated carbon (AC) was then utilized as an adsorbent for batik waste which contains heavy metal substances such as Fe2+. The purpose of this study was to determine the optimum process variation in absorbing heavy metal ion Fe contained in batik waste. Four variation methods of activated carbon synthesis were explored to determine the most suitable method of AC synthesis. The results showed that the sample synthesized using a combination physical-chemical-physical process was the best process variation resulting in percentage removal of Fe2+ of 84.81%. FTIR showed that the functional groups in mango peel were visible for all variations of the process, namely hydroxyl (-OH) derived from cellulose and hemicellulose and carboxyl (-COOH) derived from pectin. The adsorption study showed that the most suitable isotherm for all process variations was Langmuir with an R2 value of 0.9999 for the MPAC-4 sample. The adsorption mechanism is physisorption with a value of E < 8 kJ/mol based on the D-R isotherm and has the largest adsorption capacity of Qmax 8.2 mg/g.Keywords: batik waste; adsorption; activated carbon; iron waste; mango peelABSTRAKLimbah kulit mangga yang memiliki gugus fungsi karbon dapat dikonversi menjadi karbon aktif. Karbon aktif hasil sintesis (AC) tersebut selanjutnya dimanfaatkan sebagai adsorben limbah batik yang mengandung zat logam berat seperti Fe2+. Tujuan dari penelitian ini adalah untuk mengetahui variasi proses optimum dalam menyerap ion logam berat Fe yang terkandung dalam limbah batik. Terdapat 4 variasi metode sintesis karbon aktif yang diteliti untuk menentukan metode sintesis AC yang paling cocok. Hasil penelitian menunjukkan bahwa sampel yang disintesis menggunakan kombinasi proses fisika-kimia-fisika merupakan variasi proses terbaik dengan persentase penyisihan Fe2+ sebesar 84,81%. Analisis FTIR menunjukkan bahwa gugus fungsi pada kulit mangga terlihat untuk semua variasi proses, yaitu hidroksil (-OH) yang berasal dari selulosa dan hemiselulosa dan karboksil (-COOH) yang berasal dari pektin. Studi adsorpsi menunjukkan bahwa isoterm yang paling cocok untuk semua variasi proses adalah Langmuir dengan nilai R2 = 0,9999 untuk sampel MPAC-4. Mekanisme adsorpsi adalah fisisorpsi dengan nilai E < 8 kJ/mol berdasarkan isoterm DR dan memiliki kapasitas adsorpsi terbesar Qmax 8,2 mg/g.Kata kunci: limbah batik; adsorpsi; karbon aktif; limbah besi; kulit mangga
Perbandingan jenis media imobilisasi terhadap kinerja proses peruraian anaerob termofilik palm oil mill effluent Deni Frans Sakka; Salsabilla Fitri Millenia; Irfan Dwidya Prijambada
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69582

Abstract

A B S T R A C TPalm oil mill effluent (POME) is wastewater with high organic matter, the raw material of biogas production through anaerobic digestion. In anaerobic digestion, the washout effect frequently becomes a problem, along with the increasing organic loading rate (OLR) in a continuous system. Therefore, the addition of immobilization media was carried out to reduce this risk. This study aims to evaluate the effect of immobilization media type and arrangement on the performance of thermophilic anaerobic digestion of POME. Two immobilization media were evaluated,i.e., carbon fiber textile (CFT) media and natural zeolite particles. The anaerobic process performance was determined by measuring the concentration of volatile fatty acids (VFAs), soluble chemical oxygen demand (sCOD), and methane (CH4) yield. This study indicated that the immobilization media led to higher CH4 yields than the reactor without immobilization media. The CH4 yield of the reactor with natural zeolite was 0.3487 L/g sCOD, 0.3050 L/g sCOD in the reactor with CFT media, and 0.2873 L/g sCOD in the reactor without immobilization media. In addition, only natural zeolite can maintain reactor performance when the temperature accidentally increased with a recovery period of 14 days.Keywords: anaerobic digestion; biogas; carbon fiber textile; natural zeolite; POME.ABSTRAKPalm oil mill effluent (POME) merupakan limbah cair dengan kandungan organik yang tinggi sebagai bahan baku produksi biogas melalui peruraian anaerob. Dalam peruraian anaerob, efek washout selalu menjadi masalah seiring dengan meningkatnya organic loading rate (OLR) pada sistem kontinu. Oleh karena itu, dilakukan penambahan media imobilisasi untuk mengurangi risiko tersebut. Penelitian ini bertujuan untuk mengevaluasi pengaruh jenis dan pengaturan media imobilisasi terhadap kinerja peruraian anaerob termofilik POME. Dua media imobilisasi yang diuji yaitu media jenis carbon fiber textile (CFT) dan media berupa partikel zeolit alam. Kinerja proses anaerob ditentukan dengan mengukur konsentrasi asam lemak volatil (VFA), soluble chemical oxygen demand (sCOD) dan yield metana (CH4). Hasil penelitian ini menunjukkan bahwa reaktor dengan media imobilisasi menghasilkan yield CH4 yang lebih tinggi dibandingkan dengan reaktor tanpa media imobilisasi. Yield CH4 reaktor dengan zeolit alam sebesar 0,3487 L/g sCOD, 0,3050 L/g sCOD pada reaktor dengan media CFT dan 0,2873 L/g sCOD pada reaktor tanpa media imobilisasi. Selain itu, hanya zeolit alam yang dapat mempertahankan performa reaktor saat mengalami gangguan peningkatan suhu secara tiba-tiba dengan masa recovery selama 14 hari. Kata kunci: biogas; carbon fiber textile; peruraian anaerobic; POME; zeolit alam.
Mutu dan karakteristik penyalaan briket arang tempurung kelapa dengan aplikasi lapisan arang sengon pada permukaannya A Agussalim; Andi Khairana; Marwan Rajab; Maha Rezky; Ulfa Dwiyanti
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.70277

Abstract

A B S T R A C TCoconut shell charcoal briquettes have a better quality than briquettes from other biomass. However, this briquette also has a weakness, namely slow initial ignition. This study aimed to analyze the quality and ignition characteristics of coconut shell charcoal briquettes coated with sengon charcoal on both surfaces. The research materials were coconut shell and sengon wood obtained from Makassar city, South Sulawesi. Firstly, coconut shells and sengon were charcoaled. Coconut shell charcoal and sengon wood were then ground and mixed with 7% and 20% tapioca adhesive, respectively. There were four treatment ratios between coconut shell charcoal (TK) and sengon (S) used in this study, namely (1) TK/S 100/0, (2) TK/S 90/10, (3) TK/S 80 /20, and TK/S/S 0/100. The briquettes that have been made are then dried and conditioned for two weeks. The qualities of the briquettes were tested based on SNI 01-6235-2000, while the initial ignition properties and combustion rate were measured using the modified method of Davies and Abolude (2013). The results showed that the coconut shell charcoal briquettes TK/S 90/10 and 80/20 had a quality that was not significantly different from the uncoated coconut shell charcoal briquettes. In addition, layered charcoal briquettes also have ignition properties similar to sengon charcoal briquettes. Therefore, the application of sengon charcoal as a layer on two surfaces of coconut shell charcoal briquettes with a ratio of TK/S 90/10 can increase the initial ignition properties of the briquettes without significantly reducing the calorific value. Generally, the briquettes fulfilled the standard, namely the moisture content, ash content, and calorific value, except volatile matter.Keywords: coconut shell charcoal briquette; initial ignition properties; layered briquette; sengon briquetteA B S T R A KBriket arang tempurung kelapa memiliki mutu lebih baik dibanding briket dari biomassa lain. Namun di sisi yang lain, briket ini juga memiliki kelemahan pada sifat penyalaan awalnya yang lambat. Penelitian ini bertujuan untuk menganalisis mutu dan sifat penyalaan briket arang tempurung kelapa yang diberi lapisan arang sengon pada bagian permukaannya. Bahan penelitian ini adalah tempurung kelapa dan kayu sengon yang diperoleh dari kota Makassar. Tempurung kelapa dan kayu sengon diarangkan terlebih dahulu. Setelah itu, arang tempurung kelapa dan kayu sengon dihaluskan dan dicampur perekat tapioka masing-masing 7% dan 20%. Ada empat rasio perlakuan antara arang tempurung kelapa (TK) dan sengon (S) yang digunakan dalam penelitian ini, yakni (1) TK/S 100/0, (2) TK/S 90/10, (3) TK/S 80/20, dan TK/S 0/100. Briket yang telah dicetak dikeringkan dan dikondisikan selama dua pekan. Selanjutnya, mutu briket diuji berdasarkan SNI 01-6235-2000, sedangkan sifat penyalaan awal dan kecepatan pembakaran diukur masing-masing dengan menggunakan metode Davies dan Abolude (2013) yang dimodifikasi. Hasil penelitian menunjukkan briket arang tempurung kelapa berlapis, TK/S 90/10 dan 80/20, memiliki mutu tidak berbeda nyata dengan briket arang tempurung kelapa tanpa lapisan. Selain itu, briket arang berlapis juga memiliki sifat penyalaan yang menyamai briket arang sengon. Oleh sebab itu, penerapan arang sengon sebagai lapisan pada briket arang tempurung kelapa dengan rasio TK/S 90/10 mampu memperbaiki sifat penyalaan awal dari briket tanpa mengalami penurunan nilai kalor yang berarti. Secara umum, briket arang yang dibuat memenuhi standar, yakni untuk mutu kadar air, kadar abu, dan nilai kalor, kecuali kadar volatil.Kata kunci: briket arang tempurung kelapa; briket berlapis; briket sengon; sifat penyalaan awal
Optimization of cotton fabrics dyeing process using various natural dye extracts Edia Rahayuningsih; Taranipa Marfitania; Mukmin Sapto Pamungkas; Mukmin Sapto Pamungkas; Wachid Siti Fatimah
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.70397

Abstract

A B S T R A C TEfforts to substitute synthetic dyes on fabrics for natural dyes are currently increasing. Research and innovation are extremely needed to support those attempts so that the quality of natural dyes is more competitive than synthetic dyes. This study aims to optimize the dyeing parameters of cotton fabrics using natural dye extracts derived from the barks of Tegeran (Cudrania javanensis), Merbau (Intsia bijuga), Tingi (Ceriops tagal), and Jambal (Peltophorum pterocarpum), as well as Jolawe (Terminalia bellirica) fruit peel. Varied dyeing parameters included dye concentration, dyeing time and temperature, and material to liquor ratio (MLR). The fixative solutions used were alum, lime, and iron (II) sulfate. The optimized parameters were based on the values of color depth and evenness, measured colorimetrically. Furthermore, the obtained results of the dyeing process under optimized conditions were analyzed for color quality by measuring color coordinates as well as the values of color strength (K/S), washing fastness, and light fastness. The results showed that the optimal dyeing conditions for all natural dye extracts used were the code A extract concentrations (0.0113 g/mL of Tegeran; 0.0115 g/mL of Merbau; 0.0204 g/mL of Jambal; and 0.0582 g/mL of Jolawe), dyeing at 28°C, dyeing time of 30 minutes, and the MLR of 1:30. The resulting color variations were brown, gray, and golden yellow for the Tegeran extract with alum fixative. The highest K/S value was 5.56 for the fabric dyed in Tegeran extract with iron (II) sulfate fixative solution. The washing fastness values for Merbau, Tingi, Jambal, and Jolawe were 3-4 (fairly good) to 4-5 (excellent). Meanwhile, the light fastness values for all dyes were between 4 (good) and 5 (excellent). Overall, the standard procedure for cotton fabric dyeing that meets the minimum standards for textile products is obtained.Keywords: cotton fabric; color quality; natural dyes; optimization; standard procedure for dyeingA B S T R A KUsaha substitusi penggunaan pewarna sintetis pada kain dengan pewarna alami semakin meningkat belakangan ini. Hal ini perlu didukung dengan penelitian dan inovasi agar kualitas pewarna alami lebih kompetitif terhadap pewarna sintetis. Penelitian ini bertujuan untuk mengoptimalkan parameter pewarnaan kain katun dengan ekstrak pewarna alami dari kulit kayu Tegeran (Cudrania javanensis), Merbau (Intsia bijuga), Tingi (Ceriops tagal), Jambal (Peltophorum pterocarpum), dan kulit buah Jolawe (Terminalia bellirica). Parameter pewarnaan yang divariasikan antara lain konsentrasi pewarna, waktu dan suhu pewarnaan, serta rasio kain dengan volume larutan fiksator. Larutan fiksator yang digunakan adalah tawas, kapur, dan tunjung. Paramater terikat yang dioptimasikan didasarkan pada nilai ketuaan dan kerataan warna yang diukur secara kolorimetri. Selanjutnya hasil pewarnaan dengan kondisi yang teroptimasi dianalisis kualitas warna melalui pengukuran koordinat warna, nilai kekuatan warna(K/S), dan nilai tahan luntur terhadap pencucian dan cahaya. Hasil menunjukkan bahwa parameter pewarnaan yang optimal untuk semua ekstrak pewarna alami yang digunakan adalah pada konsentrasi ekstrak dengan kode A (0,0113 g/mL Tegeran; 0,0115 g/mL Merbau; 0,0204 g/mL Jambal; dan 0,0582 g/mL Jolawe), pewarnaan pada suhu kamar, waktu pewarnaan 30 menit, dan rasio kain dengan volume larutan fiksator 1:30. Variasi warna yang dihasilkan adalah warna cokelat, abu-abu, dan kuning emas untuk ekstrak tegeran dengan fiksator tawas. Nilai K/S tertinggi sebesar 5,56 untuk kain yang diwarnai dengan ekstrak Tegeran dengan larutan fiksator tunjung. Nilai uji kelunturan terhadap pencucian untuk Merbau, Tingi, Jambal, dan Jolawe adalah 3-4 (cukup baik) sampai dengan 4-5 (sangat baik). Nilai kelunturan terhadap cahaya untuk semua jenis pewarna adalah antara 4 (baik) sampai dengan 5 (sangat baik). Secara keseluruhan, didapatkan prosedur standar pewarnaan kain katun yang memenuhi standar minimum produk tekstil.Kata kunci: kain katun; kualitas warna; optimasi; pewarna alami; standar pewarnaan 
Sintesis polivinil alkohol tersulfonasi sebagai katalis dalam produksi metil ester: review Maria Gracella Irawan; Henky Muljana; Asaf Kleopas Sugih; Usman Oemar; Jessica Atin
Jurnal Rekayasa Proses Vol 16, No 1 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.70698

Abstract

A B S T R A C TSulfonated polyvinyl alcohol (PVA) can be used as a heterogeneous catalyst in esterification or transesterification reactions during methyl ester production. This catalyst with PVA support has the potential to be used commercially like Amberlyst 46. However, there are several drawbacks in the conventional methods to produce sulfonated PVA compared to Amberlyst 46. In this paper, various processes of sulfonated PVA synthesis will be discussed including the advantages and disadvantages compared to Amberlyst 46. The synthesis of sulfonated PVA catalysts can be carried out using sulfosuccinate acid reagents or other acid reagents that have sulfonic groups that act as the active sites of the catalysts. The use of sulfosuccinate acid as the reagent produces catalysts with better catalytic activity, but the resulting product is not in granule form like Amberlyst 46 and can only be used continuously for seven times. The use of chlorosulfonic acid as the reagent resulted in granular catalysts. However, the catalyst has less catalytic activity and stability, and the reagent has a relatively high environmental impact. For the synthesis performed using sulfuric acid as the reagent, no result regarding catalytic activity has been reported elsewhere. The blending of the catalyst with other polymers resulted in improvements in the thermal stability and mechanical strength of the sulfonated polyvinyl alcohol. After a careful review of the procedures, we propose blending or double cross-linking processes combined with sulfonated PVA synthesis as a promising method to increase the thermal stability and mechanical strength of the catalysts. However, it is necessary to perform further laboratory validations on the catalytic activity of the catalysts produced from the combined method because blending may reduce the acid capacity of the catalyst.Keywords: esterification catalyst, polyvinyl alcohol, sulfonation A B S T R A KPolivinil alkohol (PVA) tersulfonasi dapat digunakan sebagai katalis heterogen dalam reaksi esterifikasi atau transesterifikasi dalam produksi metil ester. Katalis dengan support polivinil alkohol ini berpotensi untuk digunakan secara komersial seperti Amberlyst 46. Akan tetapi, PVA tersulfonasi yang disintesis secara konvensional masih memiliki banyak kekurangan dibandingkan dengan Amberlyst 46. Pada kajian ini akan dibahas mengenai berbagai alternatif proses sintesis PVA tersulfonasi termasuk kelebihan dan kekurangannya jika dibandingkan dengan Amberlyst 46. Sintesis katalis PVA tersulfonasi dapat dilakukan menggunakan reagen asam sulfosuksinat (SSA) maupun reagen asam lainnya yang memiliki gugus sulfonat yang berperan sebagai situs aktif katalis. Penggunaan reagen SSA menghasilkan katalis dengan aktivitas katalitik yang baik namun produk yang dihasilkan tidak berbentuk granula seperti Amberlyst 46 dan hanya dapat digunakan ulang sebanyak tujuh kali. Penggunaan reagen asam klorosulfonat dapat menghasilkan katalis berbentuk granula, namun memiliki aktivitas katalitik dan kestabilan kurang baik, serta reagen yang digunakan cukup berbahaya. Untuk proses sintesis menggunakan reagen asam sulfat belum ada hasil mengenai aktivitas katalitik, tetapi dengan adanya blending dengan polimer lain dapat memperbaiki kestabilan termal dan kekuatan mekanik PVA tersulfonasi yang dihasilkan. Proses blending atau double cross-linking yang digabung dengan sintesis PVA tersulfonasi dapat meningkatkan kestabilan termal dan kekuatan mekanik sehingga metode gabungan ini diyakini sebagai metode yang paling potensial dilakukan untuk menghasilkan PVA tersulfonasi dengan karakteristik terbaik. Meskipun demikian, perlu dilakukan penelitian lebih lanjut disertai tahapan pengujian aktivitas katalitik pada katalis yang dihasilkan dari metode gabungan karena kemungkinan proses blending dapat mengurangi kapasitas asam pada katalis.Kata kunci: katalis esterifikasi; polivinil alkohol; sulfonasi

Page 1 of 2 | Total Record : 12