Article Per Year (5 Year)
p-Index From 2021 - 2026
2.345
P-Index
This Author published in this journals
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
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 : 44 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 44 Documents
Search

 1   2   3   4   5 
Manganese Recovery from Hydrocracking Spent Catalyst Using Citric Acid and Its Kinetics Petrus, Himawan Tri Bayu Murti; Sari, Dewi Purnama; Yuliansyah, Ahmad Tawfiequrrahman; Mufakhir, Fika Rofieq; Astuti, Widi; Iskandar, Yusuf; Bratakusuma, Danu; Virdhian, Shinta
International Series on Interdisciplinary Science and Technology Vol. 4 No. 2 (2019)
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Aiming for recovery and kinetics of manganese from hydrocracking spent catalyst using citric acid, this study has been conducted. In order to justify the performance of citric acid, a comparative study has been conducted using both inorganic and organic acids in the same pH condition of about 1,5 - 2. pH was used as the controlled variable due to the different dissociation degree of the acids. In comparison to that of inorganic acid, the manganese recovery is four times higher when citric acid was applied. Acetic acid performed 33% lower in manganese recovery compared to the citric acid. Moreover, kinetics study was conducted with three varying temperature of 30C, 60C, and 90C. From the resulted data, it can be concluded that the kinetics of mengan leaching from spent catalyst using citric acid is in accordance to the shrinking core model. The controlling step is product diffusion with activation energy (Ea) of about 23.27 kJ/mol calculated using Arrhenius expression. With higher selectivity and leaching reagent which is harmless to the environment, the application of citric acid in manganese leaching from spent catalyst will indeed support the enactment of sustainable development aspect in recycle processing
Pengaruh Penambahan Silica Nanopartikel dan Surfaktan SLS (Sodium Lignosulfonat) terhadap Proses Adsorpsi pada Enhanced Oil Recovery (EOR) Handayani, Destias Selly; Yuliansyah, Ahmad Tawfiequrrahman; Purwono, Suryo
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Surfactant flooding is a chemically enhanced oil recovery (EOR) technique that removes trapped residual oil by lowering the oil-water interfacial tension. The success of surfactant flooding is strongly affected by surfactant loss through its adsorption process on reservoir mineral rocks. Surfactant adsorption is a test method to determine whether surfactant is adsorbed in the reservoir rocks. In the surfactant adsorption test, only static adsorption was carried out. The mixed-surfactant formulation used 70% surfactant SLS, 22% PFAD, and 8% 1-octanol (w/v). Mixed-surfactant concentration variations are 0.25, 0.5, 0.75, and 1% (w/v). The IFT test results showed that the smallest IFT value at a concentration of 1% is 3.15 x 10-3 mN/M. In this research, adding silica nanoparticles (SNPs) to the mixed-surfactant solution is expected to reduce the interfacial tension (IFT) value and the amount of surfactant adsorbed in the reservoir rocks. Variations of SNPs concentration used are 0.05, 0.09, 0.15, and 0.3% (w/v). The lowest IFT test result by adding concentration SNPs of 0.09% is 2.07 x 10-4 mN/M. The adsorption test result showed that by adding SNPs with concentration 0.09%  with adsorption time of 24h is effective to used for adsorption.
Preparasi Katalisator Berbasis Biochar dari Ampas Buah Merah untuk Reaksi Transesterifikasi Minyak Jelantah Rahmah, Puspa; Yuliansyah, Ahmad Tawfiequrrahman; Wintoko, Joko
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Biodiesel can be produced from plant and animal oils by transesterification reaction using homogeneous or heterogeneous catalysts. In this study, we prepare a biochar-based catalyst, as a heterogeneous catalyst, for transesterification of used cooking oil. The biochar was made by the pyrolysis of the solid waste from the oil extraction of Papuan red fruit (Pandanus conoideus). After the pyrolysis, the solid was immersed in KOH solution to provide the kalium in the produced biochar. The biochar was then sulfonated by H2SO4 5M for 15h at 120°C. Afterwards, the catalysts were characterized by BET for surface area measurement, FTIR for functional groups on the catalyst surface determination and XRD for successive crystallography characterization. The catalytic performance was studied by conducting transesterification of used cooking oil using methanol with the prepared biochar-based catalysts. The transesterification optimum conditions were found to be oil to methanol molar ratio of 1:15, temperature of 60°C, reaction time of 2 hours and the catalyst amount of 3% of the oil weight. Furthermore, the highest biodiesel yield was obtained by the catalyst prepared from biochar that was sulfonated with 5M H2SO4 solution
Pengurangan Kadar Chrom dari Limbah Cair Industri Menggunakan Sistem Sub-Surface Flow Constructed Wetland (Ssf-Cw) dengan Tanaman Akar Wangi pada Media Kerikil dan Granul Fly Ash Hasanah, Nur Hayati; Yuliansyah, Ahmad Tawfiequrrahman; Prasetya, Agus
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Sub-Surface Flow Constructed Wetland (SSF-CW) is one of the engineered of sewage treatment systems built and designed involving aquatic plants, soil or other media and related microbes, with more controlled treatment using sub-surface flow types. The purpose of this study was to determine the ability of aquatic plants to reduce of chromium (Cr) in wastewater, to understand the effect of fly media ash and gravel media in the constructed wetland system in reducing chrom  in wastewater. The Constructed Wetland was designed made of plastic with the Sub-Surface Flow Constructed Wetland (SSF-CW) model with 3 zones, zone 1 which is inlet zone and zone 3 which is outlet having dimensions of 37 x 54.5 x 60 cm, while zone 2 which is a reaction zone with dimensions 75 x 52.6 x 43.5 cm. The results showed that overall chrom removal from wastewater in RI, RII, RIII was 85.76, 93.24, and 74.69%, respectively. During the study, there was a growth of the plants, indicated by the presence of new shoots and an increase in the weight of plants. The kinetic model for reducing chromium content in wastewater at the RI, RII and RIII reactors follows the first order equation with a value of k value of 5.3411; 2,4006; and 0.1330.
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