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All Journal ASEAN Journal of Systems Engineering Jurnal Rekayasa Proses Jurnal Bahan Alam Terbarukan Seminar Nasional Teknik Kimia Kejuangan Journal of Degraded and Mining Lands Management Jurnal Sains & Teknologi Lingkungan Konversi Journal of the Civil Engineering Forum Communications in Science and Technology Jurnal Chemurgy Jurnal Rekayasa Proses Media Ilmiah Teknik Lingkungan INSIST (International Series on Interdisciplinary Research) Jurnal Inovasi Teknik Kimia Prosiding Conference on Research and Community Services Prosiding Simposium Nasional Rekayasa Aplikasi Perancangan dan Industri Hexagon

Ahmad Tawfiequrrahman Yuliansyah

Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada

Author-ID : 517414

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Mechanical Engineering Social Sciences Other

Published : 41 Documents Claim Missing Document

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HYDROTHERMAL LIQUEFACTION OF MAHOGANY (Swietenia macrophylla) SAWDUST mulhidin, mulhidin; Yuliansyah, Ahmad Tawfiequrrahman; Prasetya, Agus
Jurnal Bahan Alam Terbarukan Vol 7, No 1 (2018): June 2018 [Nationally Accredited]
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jbat.v7i1.12410

Hydrothermal treatment is one of the thermochemical methods to convert complex organic compounds, such as organic waste and biomass, into upgraded solid, bio-oil, and other dissolved chemicals by utilizing the properties of water at near critical condition. Such method is very potential since the process is environmentally friendly and the products have more added values. In this research, conversion of mahogany sawdust (Swietenia macrophylla) using hydrothermal treatment method was studied. The experiments were conducted in a batch autoclave with temperature range of 200-300oC and initial pressure of 1 MPa. At targeted temperature, the process was hold for 30 minutes. In addition, biomass-water ratio (B/W ratio) for experiments was varied at 1:20, 2:20 and 3:20. The liquid products, which were characterized by Gas chromatography-Mass spectrometry (GC/MS) instrument, showed the presence of furfural and several organic acids, but no flavonoid compounds. Thus, coloring potential test of hydrothermal liquid was unsuccessful; there were not any color attached on the cloth specimen. On the other hand, proximate and ultimate test results indicated that solid products had high heating value (HHV) of 4625.34-4876.25 cal/g which were comparable to that of sub-bituminous coal.

Asetalisasi Gliserol Produk Samping Industri Biodiesel Menjadi Solketal Menggunakan Katalis Amberlyst-15 Kidung Wulan Utami; Hary Sulistyo; Ahmad Tawfiequrrahman Yuliansyah
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2020: PROSIDING SNTKK 2020
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

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Kajian Proses Pengolahan Limbah Bambu Apus (Gigantochloa Apus) dengan Menggunakan Metode Hydrothermal Liquefaction Rizka Lestari; Ahmad T Yuliansyah; Agus Prasetya; Hary Sulistyo
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2018: PROSIDING SNTKK 2018
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Optimasi Kondisi Operasi Ekstraksi Zat Warna Alami dari Daun Ketepeng (Terminalia Catappa) Menggunakan Response Surface Method Zakiah Awalia J S Dahlan; Edia Rahayuningsih; Ahmad Tawfiequrrahman
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2018: PROSIDING SNTKK 2018
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Valuable Metals Extraction From Hydrocracking Spent Catalyst Using Citric Acid Dewi Purnama Sari; Ahmad Tawfiequrahman; Himawan Tri Bayu Murti Petrus; Fika Rofiek Mufakir; Widi Astuti; Y Iskandar; D Bratakusuma
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2018: PROSIDING SNTKK 2018
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Solid Biofuel dari Campuran Tongkol Jagung dan Tempurung Kelapa dengan Metode Hydrothermalsebagai Substituen Energi dalam Upaya Reduksi Sampah Pertanian C. Chika Oktalia Putri; Britania Dewi Clarasinta; Ahmad Tawfiequrrahman
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2017: PROSIDING SNTKK
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Hydrothermal treatment is a thermochemical process that using subcritical water for converting biomass to produce high calorific biofuel. In this method, water actsas reactant, as well as medium of reaction. Experiments was conducted in temperature range of 200-270°C, holding time of 20-40 minutes, biomasswater ratio from 1:7.5 to 1:15 at various composition of coconut shell-corn cob. Based on experimental results, it was found that higher calorific value biofuels produced from treatments with higher temperature since more biomass was decomposed into more carbonaceous products. In addition, longer holding time also raised calorific value due to more complete decomposition. It was also indicated that increasing amount of biomass of the feed raised the calorific value of product. The highest calorific value of product of 5,12 kcal/kg was obtained from the treatment of 270°C, holding time of 30 minutes, biomass-water ratio of 1:10 at the coconut shell-corn cob ratio of 1:1

Permodelan Ekstraksi Lignin Mentah dari Black Liquor dengan Metode Asidifikasi pada pH Rendah Pasca Giffari Jusuf; Suryo Purwono; Ahmad Tawfiequrahman
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2019: PROSIDING SNTKK 2019
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Karakterisasi Larutan Polimer KYPAM HPAM untuk Bahan Injeksi dalam Enhanced Oil Recovery (EOR) Harimurti Wicaksono; Sutijan; Ahmad Tawfiequrrahman Yuliansyah
Jurnal Rekayasa Proses Vol 9, No 1 (2015)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Polymer injection is one method of Enhanced Oil Recovery (EOR), where the polymer is dissolved in water, usually the formation water. Hydrolyzed polyacrylamide (HPAM) polymer types are most commonly used. This study aims to investigate the effect of KYPAM HPAM polymer concentration and operating conditions upon the water injection in order to determine the optimal injection system. Viscosity of polyacrylamide solution was measured with a Brookfield viscometer. Variation in salinity is carried out by mixing formation water with distilled water, whereas for high salinity of formation water using evaporation method. Shear rate was varied in the range of 145 s-1, while solution temperature was varied in the range of 70  87°C , and the effect of H2S gas in the solution was conducted by saturating the solution using natural gas which has concentration of H2S as 100 ppm. The results show that the effect of salinity solution has the greatest influence on the decrease in viscosity of the solution when compared to the other factors. Decrease in viscosity was due to agglomeration process resulting precipitate of polyacrylamide in the form of vaterite and aragonite morphology. The result also show that an increase in shear rate resulting lower viscosity. The increase in temperature causes the viscosity of the solution decreases. Meanwhile, the presence of H2S in the solution reduces the viscosity of the solution due to chemical degradation. Keywords: EOR, formation water, polymer injection, hydrolyzed polyacrylamide, salinity, polymer concentration. Injeksi polimer merupakan salah satu metode dalam Enhanced Oil Recovery (EOR). Dalam hal ini, polimer terlebih dulu dilarutkan dalam air, biasanya air formasi. Poliakrilamida terhidrolisis (HPAM) merupakan salah satu jenis polimer yang paling sering digunakan. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi polimer KYPAM HPAM dan kondisi operasi pada injeksi air untuk menentukan sistem injeksi yang optimal. Larutan poliakrilamida diukur viskositasnya dengan viskometer Brookfield. Variasi salinitas dilakukan dengan mencampur air formasi dan aquades, sedangkan untuk salinitas tinggi dari air formasi dengan menggunakan metode penguapan.Variasi shear rate dilakukan pada kisaran 145 s-1, sedangkan suhu larutan divariasikan di kisaran 7087°C. Pengaruh gas H2S dalam larutan dilakukan dengan menjenuhkan larutan menggunakan gas alam yang memiliki konsentrasi H2S 100 ppm. Hasil penelitian menunjukkan bahwa salinitas memiliki pengaruh terbesar pada penurunan viskositas larutan bila dibandingkan dengan faktor-faktor lain. Penurunan viskositas disebabkan aglomerasi menghasilkan endapan poliakrilamida dalam bentuk vaterite dan morfologi aragonit. Hasil percobaan juga menunjukkan bahwa peningkatan shear rate, mengakibatkan viskositas larutan terukur rendah. Peningkatan suhu menyebabkan viskositas larutan turun, sedangkan kehadiran H2S dalam larutan mengurangi viskositas larutan karena terjadi degradasi kimia pada polimer. Kata kunci: EOR, air formasi, injeksi polimer, hydrolyzed polyacrylamide, salinitas, konsentrasi polimer

Pemanfaatan Cangkang Biji Pala sebagai Briket dengan Proses Pirolisis Rukmana; Suryo Purwono; Ahmad Tawfiequrrahman Yuliansyah
Jurnal Rekayasa Proses Vol 9, No 2 (2015)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

The abundance of nutmeg seed shells in Tidore is the reason to study the possibility to produce charcoal briquettes. The use of charcoal briquettes was expected to reduce waste of nutmeg seed shell and can be an alternative energy source with a high economic value. This study aims to investigate the effect of pyrolysis temperature and composition of tapioca adhesive to resulting quality of briquettes. The first step of the research was the preparation of nutmeg seed shells consisted of drying and size reduction into less than 20 mesh size. Afterward, the powder was put into furnace and heated to 350°C, 400°C, and 450°C for 90 minutes. During the process, volume of gas and liquids were measured every 15 minutes, while gas was sampled at 60-minute reaction. When pyrolysis was finished, about 20 g of charcoal was mixed with tapioca adhesive. The compositions of adhesive were 10%, 15%, 20%, 25%, and 30%. Finally, composite was formed in a cylindrical shape and compressed with hydraulic press at f 3 tons weight for a minute. The briquettes were then dried and analyzed with proximate analysis test. The results show that the highest calorific value was 6717.74 cal/g for material pyrolyzed at 450oC and 20% adhesive. The effect of adhesive on shatter index test showed that increasing composition of adhesive makes a better briquette quality as shown by a lower shatter index. In this study, the minimum weight loss was obtained by the addition of 30% adhesive. Keywords: briquettes, nutmeg seed shells, pyrolysis Ketersediaan cangkang biji pala yang melimpah di kota Tidore menjadi dasar dilakukannya penelitian mengenai pemanfaatan cangkang biji pala menjadi briket arang. Penggunaan briket arang diharapkan dapat mengurangi limbah cangkang biji pala dan sebagai sumber energi alternatif ramah lingkungan yang memiliki nilai ekonomi tinggi. Penelitian ini bertujuan untuk mempelajari pengaruh suhu pirolisis dan komposisi campuran perekat dengan arang cangkang biji pala terhadap kualitas briket. Tahap pertama dalam penelitian ini adalah penyiapan bahan baku berupa pengeringan dan penyesuaian ukuran cangkang biji pala sebesar 20 mesh. Tahap kedua yaitu proses pirolisis dengan cara memasukkan bubuk cangkang biji pala ke dalam tungku pirolisis (pirolisis selama 90 menit dengan variasi suhu 350oC, 400oC dan 450oC). Selama proses pirolisis berlangsung, volume gas dan cairan diukur setiap 15 menit, sedangkan pengambilan sampel gas dilakukan setelah pirolisis mencapai waktu 60 menit. Setelah dipirolisis, arang cangkang biji pala ditimbang seberat 20 gram kemudian bahan ini dicampurkan dengan perekat tapioka dengan variasi komposisi sebesar 10%, 15%, 20%, 25%, dan 30%. Setelah itu, arang cangkang biji pala dicetak dalam bentuk silinder dan dikempa dengan alat kempa hidrolik dengan berat 3 ton selama 1 menit. Briket kemudian dikeringkan dan dianalisis uji proksimat. Hasil uji proksimat menunjukkan bahwa nilai kalor yang tertinggi sebesar 6717,74 kal/g dimiliki oleh bahan hasil pirolisis suhu 450oC dengan campuran perekat 20%. Pengaruh perekat terhadap uji shatter index menunjukkan bahwa semakin tinggi kandungan perekat dalam briket maka semakin baik shatter index dari briket. Pada penelitian ini diketahui bahwa briket dengan penambahan perekat sebesar 30% mengalami kehilangan berat yang paling sedikit. Kata kunci: briket, cangkang biji pala, pirolisis

Produksi Organic Preservative dan Solid Biofuel dari Hydrothermal Treatment Tongkol Jagung dengan Variasi Temperatur Haidar Ali; Ahmad Tawfiequrrahman Yuliansyah
Jurnal Rekayasa Proses Vol 10, No 2 (2016)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Corn is one of staple food and influential commodity driving Indonesia’s economy. Indonesia currently produces as high as 19 million tons of corn which contains 50% of biomass in the form of cob. Waste from harvesting and consumption of corn, namely, corn cob (CC) is left as waste. This CC is actually a sustainable, easily accessible, and renewable biomass energy source as an alternative to Indonesia’s depleting fossil fuel reserves. Hydrothermal treatment is a conversion method that has some consequential advantages compared to other methods; e.g. the ability to treat high-moisture biomass like CC and the possibility to use lower temperature. This research aims to produce and characterize liquid and solid fuel subsequent to hydrothermal treatment of CC obtained from Sleman, Yogyakarta. After size reduction, fine particles were mixed with water to form slurry. Slurry was heated in an autoclave for hydrothermal treatment at initial pressure of 2.0 MPa and was held for 200 °C, 240 °C, and 270 °C in 30 minutes. The solid and liquid products were then separated. Liquid was analyzed using GC-MS and solid by using AAS. The result showed that, in comparison to raw material, solid product had higher carbon content which resulted in the increase of calorific value of the solid biofuel. The calorific value of solid product ranged from 19,59 -22,02 MJ/kg or 20,93-35,87% higher than raw materials and 4-17% higher than average coal used in Indonesia. Major component in liquid product are N, N-dimethyl formamide, furfural, and phenolic compound, with benzoic acid present as minor component. The potential of liquid products as organic preservatives are examined by testing the tenacity of wood against termite according to ASTM D3345-74 standard method. Result showed that liquid product were effective in exhibiting termiticidal activity and temperature 200 °C showed the optimum condition. ABSTRAKJagung merupakan salah satu makanan pokok dan komoditas yang berpengaruh terhadap ekonomi Indonesia. Produksi jagung Indonesia saat ini mencapai 19 juta ton dan sebanyak 50% berupa tongkol. Limbah dari pemanenan dan konsumsi jagung adalah tongkol jagung (CC) yang cepat busuk dan banyak kelemahannya yang harus ditangani. Sebetulnya, CC merupakan solusi yang berkelanjutan, mudah diperoleh, serta sumber energi terbarukan berupa biomassa yang dapat menjadi alternatif solusi untuk berkurangnya cadangan bahan bakar fosil di Indonesia. Hydrothermal treatment adalah metode konversi yang memiliki beberapa keunggulan jika dibandingkan dengan metode lain seperti kemampuan untuk menangani kandungan air yang tinggi pada CC dan kemungkinan penggunaan temperatur yang rendah. Penelitian ini bertujuan untuk mengkarakterisasi cairan dan padatan yang dihasilkan dari proses hydrothermal terhadap tongkol jagung yang diperoleh dari Sleman, Yogyakarta. Setelah proses reduksi ukuran, partikel halus tersebut dicampur dengan air sehingga terbentuk slurry. Slurry dipanaskan dalam autoclave untuk dijalankan proses hydrothermal dengan tekanan awal sebesar 2.0 MPa dan dijalankan pada suhu 200 °C, 240 °C, dan 270 °C dengan holding time selama 30 menit. Padatan dan cairan yang dihasilkan dipisahkan. Cairan dianalisis dengan GC-MS sedangkan padatan dengan AAS. Hasil menunjukkan bahwa dengan perbandingan bahan baku, padatan memiliki kandungan karbon yang lebih tinggi sehingga terjadi kenaikan nilai kalor. Nilai kalor padatan berkisar antara 19,59-22,02 MJ/kg atau 20,93-35,87% lebih tinggi dari bahan baku dan 4-17% dari batubara yang ada saat ini. Cairan yang dihasilkan didominasi oleh N,N-dimethyl formamide, furfural, phenolic compound serta sedikit asam berupa benzoic acid. Pengujian produk cairan sebagai pengawet organik dilakukan dengan pengujian ketahanan kayu terhadap rayap sesuai dengan standar ASTM D3345-74. Hasil menunjukkan bahwa cairan yang dihasilkan cukup efektif sebagai pembunuh rayap dan variasi temperatur 200 °C memberikan kondisi yang optimum.

Co-Authors Achmad Diansyukma Agus Prasetya Ahmad Hanafi Arief Budiman Asep P Zainuddin Aziz Askaputra Bagus Putro Budi Utomo Bratakusuma, Danu Britania Dewi Clarasinta Budi Kamulyan C. Chika Oktalia Putri Cahyono, Rochim Bakti Claudino de Almeida Cabral D Bratakusuma Danu Bratakusuma Dedi Eko Yunanto Dewi Purnama Sari Dewi Purnama Sari Dwi Saputri Dwi Saputri Edia Rahayuningsih Erlina Kurnianingtyas Fajar Marendra Fajar Marendra Fami Amalia Putri Fika Rofiek Mufakir Fika Rofieq Mufakhir Fitriani Fitriani Haidar Ali Handayani, Destias Selly Harimurti Wicaksono Hary Sulistyo Hasanah, Nur Hayati Himawan Tri Bayu Murti Petrus Imam Karfendi Putro Indra P Hakim Kidung Wulan Utami Lestari, Dwi Indah Lisendra Marbelia Mahfudl Sidiq Muhayyat Marendra, Fajar Mufakhir, Fika Rofieq Muhamad Johar Ardany Muhammad A. A. Ramadhan, Muhammad Muhammad Irsan B Muhammad Kurniawan Adiputra mulhidin, mulhidin Pasca Giffari Jusuf Rahmah, Puspa Reno Imam Arthapersada Riski Amalia, Riski Rizka Lestari Rizki Laksono, Rizki RR. Ella Evrita Hestiandari Rukmana Saputri, Dwi Sarto Sarto Septina AVIA Avia Shinta Virdhian shinta virdhian, shinta Sri Puji Saraswati Suprianto Suprianto Suryo Purwono Sutijan Wahyu Wilopo Widi Astuti Widi Astuti Widi Astuti Y Iskandar Yuni Rosita Yusuf Iskandar Zakiah Awalia J S Dahlan

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