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Analisis perubahan sistem kualitas udara Kota Yogyakarta pada masa pandemi COVID-19 Himawan Novianto; Muhammad Mufti Azis; Hilya Mudrika Arini
Jurnal Rekayasa Proses Vol 16, No 2 (2022)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.71888

Abstract

Beberapa penelitian membahas penurunan konsentrasi polutan udara selama masa pandemi COVID-19, namun belum banyak penelitian yang membahas kaitan antara variabel kualitas udara dan tingkat mobilitas masyarakat. Penelitian ini menyelidiki keterkaitan hubungan antara variabel polutan udara, faktor meteorologi, dan tingkat mobilitas masyarakat di Kota Yogyakarta. Fenomena hubungan sistem kualitas udara dan mobilitas masa pandemi COVID-19 tahun 2020 terbagi dalam dua periode: (a) Pembatasan Aktivitas (April s.d. Juli 2020) dan (b) Normal Baru (Agustus s.d. Desember 2020). Kualitas udara Kota Yogyakarta sebelum dan pada masa pandemi COVID-19 menunjukkan perbaikan, dari kategori Baik: 31,85% menjadi 90,37% ISPU (chi-square asymp.  sig.  < 0,05).   Polutan udara PM10, SO2, dan CO menurun sebesar 18%, 93%, dan 74%, sedangkan O3 meningkat sebesar 104% pada masa pandemi COVID-19 tahun 2020. Polutan udara primer PM10, SO2, dan CO berhubungan positif terhadap faktor meteorologi penyinaran matahari, tetapi berhubungan negatif terhadap polutan udara sekunder O3 serta faktor meteorologi suhu udara, kelembaban udara, curah hujan, dan kecepatan angin. Pembatasan aktivitas masyarakat di luar rumah secara umum menyebabkan perbaikan kualitas udara, di mana penurunan mobilitas transportasi menjadi variabel yang mempengaruhi penurunan polutan udara primer di Kota Yogyakarta. Pembatasan aktivitas mempengaruhi polutan udara sekunder, di mana kenaikan O3 terjadi ketika mobilitas dalam ruangan dan transportasi meningkat.
Kinetic Modeling of C3H6 Inhibition on NO Oxidation over Pt Catalyst Muhammad Mufti Azis; Derek Creaser
Bulletin of Chemical Reaction Engineering & Catalysis 2016: BCREC Volume 11 Issue 1 Year 2016 (April 2016)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.11.1.412.27-33

Abstract

Exhaust after treatment for lean burn and diesel engine is a complex catalytic system that consists of a number of catalytic units. Pt/Al2O3 is often used as a model Diesel Oxidation Catalyst (DOC) that plays an important role to facilitate oxidation of NO to NO2. In the present study, we proposed a detailed kinetic model of NO oxidation as well as low temperature C3H6 inhibition to simulate temperature-programmed reaction (TPR) data for NO oxidation over Pt/Al2O3. A steady-state microkinetic model based on Langmuir-Hinshelwood mechanism for NO oxidation was proposed. In addition, low temperature C3H6 inhibition was proposed as a result of site blocking as well as surface nitrite consumption. The model can explain the experimental data well over the studied temperature range. 
Experimental and Kinetic Modeling of Galactose Valorization to Levulinic Acid Retno Ringgani; Muhammad Mufti Azis; Rochmadi Rochmadi; Arief Budiman
Bulletin of Chemical Reaction Engineering & Catalysis 2022: BCREC Volume 17 Issue 2 Year 2022 (June 2022)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17.2.14032.451-465

Abstract

Levulinic acid, a versatile chemical building block, was derived from C6-sugar galactose using sulfuric acid as the catalyst. Galactose is monosaccharide of polysaccharides constituent that is mostly contained in third generation biomass, macro-microalgae. It currently receives high attention to be a source of renewable feedstock. The effect of temperature, catalyst concentration and initial substrate loadings were studied for 60 min, in the temperature range of 150–190 °C, acid concentration of 0.25–0.75 M and initial substrate loading of 0.05–0.25 M. The highest levulinic acid yield of 40.08 wt% was achieved under the following conditions: 0.05 M galactose, 0.75 M acid concentration, 170 °C temperature, and 40 min reaction time. The kinetic model was developed by first order pseudo-irreversible reaction. The results showed that the proposed model could capture the experimental data well. These results suggested that galactose, derived from macro- and micro-algae, can potentially be converted and applied for platform chemicals. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Microwave-Assisted Pyrolysis Process of Sengon Sawdust by Using Ni/Al2O3 Catalyst Wulandari, Lisa Ayu; Azis, Muhammad Mufti
Procedia of Engineering and Life Science Vol 4 (2023): Proceedings of the 6th Seminar Nasional Sains 2023
Publisher : Universitas Muhammadiyah Sidoarjo

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Abstract

Microwave-assisted pyrolysis (MAP) process is one of the alternative biomass pyrolysis processes currently being developed. This process aims to increase the yield of bio-oil and reduce residues during the pyrolysis process. One of the challenges faced in this process is the low thermal conductivity of the biomass which will also affect the quality of the bio-oil produced. The addition of a catalyst is intended to increase the yield of bio-oil and the quality of bio-oil. In addition, this process is also carried out by adding an absorber to increase the thermal conductivity of the biomass. Ni/Al2O3 catalyst was synthesized by wet impregnation method with variations of 8%, 11% and 12.5% ​​nickel loading. Furthermore, the catalyst was mixed with sawdust of sengon (Paraserianthes falcataria) and coconut charcoal as absorber. The microwave is set at a maximum temperature of 500 °C with an operating time of 60 minutes. Pyrolysis results showed that the addition of catalyst and absorbent was able to increase bio-oil production, with the percentage of bio-oil being 25.2%, 27%, and 33% respectively compared to pyrolysis without catalyst which only reached 11%. GC-MS analysis of bio-oil showed various hydrocarbon components in each variation, with the main components being phenol and benzene.
Thermal Stability Test and Formulation of Sodium Lignosulfonate with Isoamyl Alcohol as EOR Surfactant Andriani, Anisa Novi; Azis, Muhammad Mufti; Purwono, Suryo
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

Sodium lignosulfonate (SLS) is a promising low-cost surfactant that can be prepared from biomass. There has been large interest to utilize SLS as a chemical Enhanced Oil Recovery (EOR) surfactant. For that purpose, SLS is often mixed with other chemicals such as alcohols. The aim of this study was to find the best formulation of mixed-surfactant and to perform its thermal stability. The resulting mixed-surfactant was then characterized with variety of tests: aqueous stability, phase behavior, and IFT values. We found that a mixture that consists of 50 wt.% SLS, 30 wt.% Isoamyl Alcohol, and 20 wt.% of Palm Fatty Acid Distillate (PFAD) soap gave ultralow IFT at 1.864 × 10-3 mN/m. Phase behavior test shows that 1 wt% of mixed-surfactant formed a Winsor Type III. Subsequently, thermal stability test was conducted at 70°C for 90 days. The results showed that the IFT value fluctuates within the range of 10-3 mN/m for the first three weeks. After three weeks, the IFT values tend to increase to 10-2 mN/m until the end of the test. Hence, although ultralow IFT was achieved in the beginning of the test, further study is needed to improve the long-term stability of the present mixed-surfactant
Preparation and Characterization of Ni/H-ZSM-5 Catalysts for Producing Green Diesel from Palmitic Acid Kurniati, Sayekti; Azis, Muhammad Mufti; Dwiatmoko, Adid Adep
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

Biofuel is a promising alternative as a sustainable energy resource in the transportation sector in Indonesia. Green diesel is one of biofuels that can be produced from feedstock containing fatty acid. Fatty acid conversion to green diesel can be conducted via hydrodecarboxylation or hydrodeoxygenation process. Catalyst Ni/H-ZSM-5 is a potential catalyst to convert fatty acid to n-alkane which is the main component in green diesel. In this work, we prepared Ni/H-ZSM-5 catalyst with various Ni loading of 7%, 13%, 18%, and 25%, respectively. The catalysts were synthesized according to a simple incipient wetness impregnation method. Those catalysts were characterized with X-ray fluorescence, Field-Emission Scanning Electron Microscopy, and NH3-TPD. The highest nickel-loading catalyst, Ni 25%/H-ZSM-5, gave the best dispersion. NH3-TPD results showed the presence of two acid sites, namely Brønsted acid site and Lewis acid site. The presence of Brønsted acid sites is crucial to facilitate fatty acid conversion to n-alkane.
Catalytic Pyrolysis of Corn Cob Using Fe-Ni/Char Catalyst Safitri, Mutia; Azis, Muhammad Mufti; Wintoko, Joko; Kristanto, Jonas; Caroko, Novi
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

There is a growing interest to convert biomass waste such as corn cob to biofuel. Thermal conversion such as pyrolisis may play an important role to produce bio-oil. The objective of this research was to develop a kinetic study of catalytic pyrolysis of corn cob over Fe-Ni/Char catalyst using Thermogravimetric Analysis (TGA). The solid catalyst was prepared by impregnation method. The ratio of the percentages of Fe and Ni metals in the X-Ray Fluorescence (XRF) analysis of the catalyst was close to 1:1, resulting in metal loading values of 2.5% (1.062% and 1.013%), 5% (2.291% and 2.794%), and 10% (4.947% and 5.417%) for the catalyst. The pyrolysis experiments were performed using various catalyst loadings of 0, 2.5, 5, and 10%. In addition, the present study also investigated the influence of heating rates of 5, 10, and 20 K min-1. Two isoconversion models, Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) were utilized to determine the activation energies. The activation energies calculated using the KAS and OFW models revealed a consistent trend, with values of activation energy of corn cob pyrolysis around 124 - 303 kJ/mol and 133 - 313 kJ/mol, respectively.
Demineralisasi Batubara Berkadar Abu Tinggi dengan Leaching Menggunakan Alkali Ikhsana, Mifta Aulia; Azis, Muhammad Mufti; Purwono, Suryo
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2023: PROSIDING SNTKK 2023
Publisher : Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

The study was comdustred on the demineralization of Jambi coal with high ash content as an effort to improve quality. The coal selected first crushed to -80 + 115 mesh. Demineralization was carried out using leacjing process with NaOH 20, 25, and 30% (%weight). The best parameter was used in subsequent leaching process to determine the effect of temperature of 50, 70, 90oC. The result showed that the percentage of demineralization increased with increasing demineralization reduction 34%
Mathematical modelling and simulation of hydrotropic delignification Indah Hartati; Wahyudi Budi Sediawan; Hary Sulistyo; Muhammad Mufti Azis; Moh Fahrurrozi
Jurnal Rekayasa Proses Vol 13 No 1 (2019): Volume 13, Number 1, 2019
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.42364

Abstract

Delignification is a fundamental step in bio-refinery for lignocellulose feedstock processing. Hydrotropic delignification is considered as a promising alternative compared to other conventional delignification processes due to the use of mild chemicals. In this paper, a quantitative description of hydrotropic delignification for a cylindrical biomass particle is presented by using fundamental concepts of chemical kinetics and transport processes. The development of hydrotropic delignification model was based on following assumptions: i) lignin in the biomass is immobile, ii) delignification is considered as a simultaneous process which involves intra-particle diffusion of hydrotropic agent followed by second order reaction for lignin and hydrotropic chemical, as well as intra-particle product diffusion. Finite difference approximation was applied to solve the resulting partial and ordinary differential equations. The simulation results of the proposed model may describe the concentration profiles of lignin, hydrotropic agent and soluble product distributions in a cylindrical solid particle as a function of radial position and time. In addition, the model could also predict the concentration of hydrotropic agent and soluble product in the liquid phase as well as the yield and conversion as a function of time. A local sensitivity analysis method using one factor at a time (OFAT), has been applied to investigate the influence of particle size and hydrotropic agent concentration to the yield and conversion of the hydrotropic delignification model. Validation of the proposed model was conducted by comparing the numerical results with an analytical solution for a simple case diffusion in cylinder with constant surface concentration and in the absence of chemical reaction. The validation result showed that the hydrotropic delignification model was in good agreement with the analytical solution.
Life cycle assessment (LCA) kegiatan bank sampah di pedesaan (Bank Sampah Asoka Berseri, Desa Sokosari, Tuban) Titi Tiara Anasstasia; Muhammad Mufti Azis
Jurnal Pengelolaan Lingkungan Berkelanjutan (Journal of Environmental Sustainability Management) JPLB, Vol 4, No 3 (2020)
Publisher : Badan Kerjasama Pusat Studi Lingkungan (BKPSL) se-Indonesia bekerjasama dengan Pusat Penelitian Lingkungan Hidup IPB (PPLH-IPB)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36813/jplb.4.3.537-551

Abstract

Life Cycle Assessment (LCA) is a method that can be used to evaluate the waste management system based on the potential impact produced. The Asoka Berseri Waste Bank in Tuban Regency is an example of a waste processing unit that aims to reduce the possible effects of waste generation both in quality and quantity in rural areas. This study aimed to calculate and evaluate the potential environmental impacts from the waste bank, then compared it with conventional waste management carried out by the community. The method used was based on CML Baseline v4.4 and ISO 14000 standards, including goal and scope, life cycle inventory (LCI), life cycle impact assessment (LCIA) and interpretation. The LCA simulation was carried out with the OpenLCA software to calculate the value of the potential impact of each kilogram of waste produced. Based on the simulation results, every 1 kg of waste managed by the waste bank produced a lower potential global warming impact (6.395 kg CO2 eq.) than open dumping (13.057 kg CO2 eq.) and open burning (10.850 kg CO2 eq.). Further processing of solid waste into RDF and compost at the Waste Bank present a lower potential environmental impact and increase community income.