Dimethyl Ether Production Research Articles

Hierarchical Ag3VO4 Nanorods as an Excellent Visible Light Photocatalyst for CO2 Conversion to Solar Fuels

The potential of photocatalytic CO2 conversion is significant for the production of fuels and chemicals, while simultaneously mitigating CO2 emissions and addressing environmental concerns. Despite the current drawbacks of single metal-based photocatalysts, such as lower performance, uncontrollable selectivity, and instability, this study focuses on the synthesis of Ag3VO4 nanorods using the sol–gel method. The goal is to create a highly effective catalyst for visible light-responsive CO2 conversion. The successful synthesis of Ag3VO4 nanorods with a nanorod structure, functional under visible light, resulted in the highest yields of CH4 and dimethyl ether (DME) at 271 and 69 µmole/g-cat, respectively. The optimized Ag3VO4 nanorods demonstrated performance improvements, with CH4 and DME production 6.4 times and 4.5 times higher than when using V2O5 samples. This suggests that Ag3VO4 nanorods facilitate electron transfer to CO2, offer short pathways for electron transfer, and create empty spaces within the nanorods as electron reservoirs, enhancing the photoactivity. The prolonged stability of Ag3VO4 in the CO2 conversion system confirms that the nanorod structure provides controllable selectivity and stability. Therefore, the fabrication of nanorod structures holds promise in advancing high-performance photocatalysts in the field of photocatalytic CO2 conversion to solar fuels.

Assessment of Hazards in the High‐Pressure Continuous Flow Reactor for Dimethyl Ether (DME) Synthesis

AbstractThe objective of this study is to conduct a thorough hazard analysis specifically tailored to identify hazards and suggest precautions associated with the intricate process of dimethyl ether (DME) production. This exothermic nature of DME production introduces the critical concern of thermal runaway. Furthermore, the DME synthesis process demands precise control over both pressure and flow rate. These parameters are important for increasing DME selectivity and CO conversion. Inadequate monitoring of these values may not only prevent the synthesis from proceeding but may also lead to major risks to health and safety. For this reason, proactive measures must be implemented to eliminate or minimize the risks. The significance of such measures cannot be overstated, as they serve to safeguard not only the integrity of the synthesis process but also the surrounding environment and human health. To delve deeper into the hazard evaluation, a comprehensive Hazard and Operability (HAZOP) analysis has been carried out, focusing specifically on the reactor within the DME process. This methodical examination involves a systematic review of potential deviations, identifying the associated hazards, and proposing effective preventive measures. The HAZOP analysis serves as a pivotal tool in ensuring the overall safety and reliability of the DME process.

Constructing type II heterojunction of 2D/1D Pg-C3N4/Ag3VO4 nanocomposite with high interfacial charge separation for boosting photocatalytic CO2 reduction under solar energy

The well-designed, template-free synthesis of 2D protonated g-C3N4 nanosheets (Pg-C3N4) coupled with novel 1D Ag3VO4 nanorods has been investigated to construct 2D/1D interface heterostructures with strong electrostatic interactions between the positively charged 2D Pg-C3N4 nanosheets and the negatively charged 1D Ag3VO4 nanorods. The coupling of Pg-C3N4 and Ag3VO4 with desirable characteristics resulted in a 2D/1D interface heterojunction with a type II charge carrier transfer mechanism, effectively maintaining and utilizing charge carriers. The 2D/1D Pg-C3N4/Ag3VO4 exhibited remarkable photocatalytic performance for CO2 conversion with H2O, resulting in maximum CH4 and dimethyl ether (DME) production of 352.3 and 130.9 µmol/g-cat, respectively. A quantum yield of 0.23 % for CH4 generation was achieved over the 2D/1D Pg-C3N4/Ag3VO4, which was 2.9 and 1.4 times higher than that of the Pg-C3N4 and Ag3VO4 samples, respectively. The improvement in photocatalytic performance primarily stems from the effective interaction between Pg-C3N4 and ternary Ag3VO4, leading to enhanced transfer and separation of photoinduced charge carriers through the creation of a type II heterojunction. The findings of this study are useful in designing template-free heterojunctions for photocatalytic CO2 conversion and other solar energy applications.

The Unimolecular Decomposition Mechanism of Trimethyl Phosphate.

Trimethyl phosphate (TMP), an organophosphorus compound (OPC), is a promising fire-retardant candidate for lithium-ion battery (LIB) electrolytes to mitigate fire spread. This study aims to understand the mechanism of TMP unimolecular thermal decomposition to support the integration of a TMP chemical kinetic model into a LIB electrolyte surrogate model. Reactive intermediates and products of TMP thermal decomposition were experimentally detected using vacuum ultraviolet (VUV) synchrotron radiation and double imaging photoelectron photoion coincidence (i2PEPICO) spectroscopy. Phosphorus-containing intermediates such as PO, HPO and HPO2 were identified. Sampling effects could successfully be obviated thanks to photoion imaging, which also showed evidence for isomerization reactions upon wall collisions in the ionization chamber. Quantum chemical calculations performed for the unimolecular decomposition of TMP revealed for the first time that isomerization channels via hydrogen and methyl transfer (barrier heights of 65.9 and 72.6 kcal/mol, respectively) are the lowest-energy primary steps of TMP decomposition followed by CH3OH/CH3/CH2O or dimethyl ether (DME) production, respectively. We found an analogous DME production channel in the unimolecular decomposition of dimethyl methylphosphonate (DMMP), another important OPC fire-retardant additive with a similar molecular structure to TMP, which are not included in currently available chemical kinetic models.

Comparative assessment of simulation-based and surrogate-based approaches to flowsheet optimization using dimensionality reduction

This work proposes a framework for simulation-based and surrogate-based reduced space Bayesian optimization of process flowsheets. The framework uses global sensitivity analysis for dimensionality reduction via the identification of critical process variables that contribute significantly to the variability of the objective function (e.g. productivity and operating costs). Both simulation- and surrogate-based algorithms are applied to a biopharmaceutical and a chemical process simulator for the production of plasmid DNA and dimethyl ether (DME), respectively. Their capabilities are assessed in terms of the trade-off between computational effectiveness and solution accuracy. Results indicate that simulation-based Bayesian optimization achieves better objective function values, while surrogate-based Bayesian optimization is more computationally effective.

The catalytic performance of γ-Al2O3/red clay as a highly active, selective, and stable catalyst for methanol dehydration to dimethyl ether at competitive low reaction temperature

This study aims to a more environment eco-friendly approach for producing dimethyl ether (DME), as an alternative fuel, through the dehydration of methanol. The method involves utilizing Egyptian natural red clay (ERC) that has been modified with various percentages of γ-Al2O3 (ranging from 3 to 30 wt%) as catalysts. The most active catalyst (10 % γ-Al2O3/ERC) was then modified with varying HCl percentages (3–7 wt%). The synthesized catalysts properties were examined by various techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2-sorption analysis, and transmission electron microscopy (TEM). The surface acidity of the catalysts was assessed using two methods: dehydration of isopropyl alcohol and chemisorption of pyridine and 2,6-dimethyl pyridine. The results of the catalytic activity study reflected that the treatment of ERC by HCl and γ-Al2O3 improved its activity toward DME production. Specifically, the 5 % HCl/10 % γ-Al2O3/ERC catalyst displayed outstanding activity, achieving conversion value of 90 % with 100 % selectivity to DME at 200 °C. Furthermore, this catalyst demonstrated long-term stability, as it maintained its performance over one week without deactivation. Acidity, and the textural characteristics were identified as the key factors contributing to the remarkable improvement in catalytic activity.

The effect of natural waste filter on dimethyl ether production from low calorific coal gasification

In Indonesia, rapid population growth has increased energy demand, especially in the transportation and power generation sectors. The Indonesian government has been active in promoting the use of renewable energy, but the transition from fossil energy is still faced with various challenges, including limited technology and adequate infrastructure. Apart from that, Indonesia's large potential in coal is the main factor slowing down this energy transition. One promising alternative is to convert coal into Dimethyl Ether (DME) through the gasification process, which is a thermochemical process for converting solid fuel into gas, producing syngas containing H2, CO, and CH4. Synthesis purification is essential to produce high-purity DME. This process involves the use of filter materials such as zeolite and rice husk charcoal to remove contaminants such as sulfur. Zeolite, with its chemical absorption properties and regular pore structure, is effective in absorbing H2S from syngas. Meanwhile, rice husk charcoal, which is an agricultural waste rich in silica and has a porous structure, has shown potential as an absorbent material to reduce H2S content in gas. In research on the use of various filter material compositions in the up-draft type coal gasification process with CuO–ZnO–Al2O3 and ZSM-5 catalysts, it was found that a 3:7 ratio for zeolite and rice husk charcoal provided optimal performance. This ratio not only increases CH4 and CO levels in syngas, but is also effective in reducing H2S content. The research results showed that the highest DME production reached 90.10% at a ratio of 3:7, while at a ratio of 2:8 and 5:5, production was 81.61% and 73.64% respectively. These findings emphasize the importance of using diverse filter materials in improving syngas quality and DME synthesis efficiency, strengthening steps to accelerate the energy transition towards more sustainable solutions in Indonesia.

Improving Net Energy Efficiency of Dimethyl Ether Production Process by Methanol Dehydration

Dimethyl ether (DME) is a source of fuel that produces clean energy for the future. Methanol can be used as a raw material for the manufacture of DME as a natural gas that is treated for synthesis. This paper evaluates how to improve net energy efficiency in DME production and how to review the net energy efficiency calculations in DME production. Methods used for production of DME are methanol dehydration, thermodynamics examination, also improving the net energy efficiency of DME with the addition of the heat exchanger (E-100), the addition of a heater (E-104) before entering a column (T-102), and moved the mixer position before the heater (E-100). By modifying the addition of a heat exchanger (E-100), heater (E-104), and changing the position of the mixer in DME production, it has been proven that it can reduce energy requirements in the dimethyl ether synthesis process from methanol and increase net energy efficiency by up to 98.83%. The results of the case study indicate that the addition heat exchanger (E-100) able to reduce the heater load after the creation process and remove the cooler (E-101) that existed before creation, then the addition of the heater (E-104) serves to reduce the load of Qcond2 and Qreb2 on columns (T-102), also the position of the mixer for the methanol recycling flow is moved before the heater (E-100) is intended to remove the heaters (E-103). Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Reducing Energy Consumption in the Synthesis of Dimethyl Ether (DME) from Methanol Dehydration by Modifying Heat Transfer Unit Using Aspen HYSYS

In the pursuit of a transport sector free from fossil fuels, the incorporation of Dimethyl ether (DME) emerges as a commendable ecological substitute. The DME is a synthetically produced serves as a viable alternative to conventional fuels such as diesel and liquified petroleum gas (LPG). The Dimethyl Ether (DME) production is carried out by catalytic dehydration of methanol over an acidic zeolite-based catalyst. The technological process for the DME synthesis was simulated using Aspen HYSYS based on the combined operating parameters of the reaction dynamic model for the methanol dehydration reaction. This paper attempts to evaluate a modification in dehydration of methanol process to reducing energy consumption by modifying heat transfer unit. The heater and cooler heat transfer units were converted into heat exchangers (HE) by utilizing the output of the process that can be used for other processes so that energy consumption is reduced. The temperature of reaction and the heat transfer unit are modified to reduce energy consumption from 11.850 MMBtu/h to 7.6291 MMBtu/h by changing one heater and one cooler with two heat exchangers. Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The Impact of Bifunctional Catalyst Synthesis Method on Methanol and Dimethyl Ether Production from CO2 and H2

The Impact of Bifunctional Catalyst Synthesis Method on Methanol and Dimethyl Ether Production from CO2 and H2

Techno-economic assessment of renewable dimethyl ether production pathways from hydrogen and carbon dioxide in the context of power-to-X

Dimethyl ether (DME) is an emerging alternative to traditional diesel and LPG as a power-to-X product. This study employs kinetic models to simulate potential DME production routes, assessing key technical and economic performance indicators for comparison. Aspen Plus, a commercial process flowsheet simulation tool, is used alongside Pinch methodology for heat integration. Four production routes are examined: two direct, converting feed gas directly to DME, and two indirect, involving methanol as an intermediate step. For one case in each, CO2 is initially converted to CO via the reverse water gas shift process (rWGS). Post heat integration, all routes exhibit higher cooling demand, with significant energy savings, notably in the indirect pathways. Indirect routes achieve power-to-fuel efficiencies of up to 39.6%, considering electrolysis and carbon capture. Direct routes excel in carbon conversion efficiencies, reaching 92.6%. Economically, indirect routes have higher upfront costs but lower operational expenses due to better energy efficiencies. Direct CO2 conversion yields the lowest levelized manufacturing costs at 2.45 €/kg, closely followed by the indirect route with rWGS. Further research is needed to enhance kinetic models and reduce simulation result uncertainty for direct conversion.

Optimizing Renewable Energy Integration for Sustainable Fuel Production: A Techno-Economic Assessment of Dimethyl Ether Synthesis via a Hybrid Microgrid-Hydrogen System

This study offers an in-depth analysis and optimization of a microgrid system powered by renewable sources, designed for the efficient production of hydrogen and dimethyl ether—key elements in the transition toward sustainable fuel alternatives. The system architecture incorporates solar photovoltaic modules, advanced battery storage solutions, and electrolytic hydrogen production units, with a targeted reduction in greenhouse gas emissions and the enhancement of overall energy efficiency. A rigorous economic analysis was conducted utilizing the HYSYS V12 software platform and encompassing capital and operational expenditures alongside profit projections to evaluate the system’s economic viability. Furthermore, thermal optimization was achieved through heat integration strategies, employing a cascade analysis methodology and optimization via the General Algebraic Modeling System (GAMS), yielding an 83% decrease in annual utility expenditures. Comparative analysis revealed that the energy requirement of the optimized system was over 50% lower than that of traditional fossil fuel-based reforming processes. A comprehensive assessment of CO2 emissions demonstrated a significant reduction, with the integration of thermal management solutions facilitating a 99.24% decrease in emissions. The outcomes of this study provide critical insights into the engineering of sustainable, low-carbon energy systems, emphasizing the role of renewable energy technologies in advancing fuel science.

Techno-Economic Analysis of Dimethyl Ether Production from Different Biomass Resources and Off-Grid Renewable Electricity

Techno-Economic Analysis of Dimethyl Ether Production from Different Biomass Resources and Off-Grid Renewable Electricity

Simulation of dimethyl ether production as LPG substitute using LNG from Arun terminal with tri-reforming and direct synthesis method

Increased demand for LNG compels Indonesia to import to meet these needs. Substituting LNG with alternative fuel emerges as a strategy to reduce LPG imports. One such alternative can be used for LPG substitution is Dimethyl Ether. Dimethyl ether is a colorless compound possesses a heating value of 30,5 MJ/kg and an energy equivalency with LPG ranging between 1,56 – 1,76. Dimethyl ether can be directly synthesized from synthetic gas produced through natural gas reforming. Production of synthetic gas from natural gas employs the tri-reforming method which integrating steam reforming, dry reforming, and partial oxidation methods in a single reactor offering optimal energy utilization advantages and minimal environmental impact. Dimethyl ether production from synthetic gas is using direct synthesis method, combining methanol synthesis and dehydration in a single reactor providing high conversion advantages compared to indirect synthesis method. Simulation was carried out using process simulator program ASPEN Plus V11. Based on the simulation results, dimethyl ether yield and selectivity is 99.62%.

Non‐Oxidative Conversion of Methanol to Dimethyl Ether, Methyl Formate and Dimethoxymethane over Cu/Hβ Catalyst: Tailoring Product Selectivity

AbstractHerein, we present the production of either dimethyl ether (DME), methyl formate (MF) or dimethoxymethane (DMM), representing pivotal molecules for the green transformation of fuels and chemical industry, by the non‐oxidative gas‐phase conversion of methanol under the same reaction conditions. The product selectivity is optimized by tailoring the acidic and dehydrogenative sites of the bifunctional Cu/Hβ catalyst system by varying the SiO2/Al2O3 ratio of the Hβ zeolite (25 and 520) and the Cu loading (0.5 and 20 wt %). At 240 °C, >99 % (DME), 74.5 % (MF), and 77.3 % (DMM) selectivity is achieved with the respective catalysts 0.5 %Cu/Hβ(25), 20 %Cu/Hβ(520), and 0.5 %Cu/Hβ(520). High acidic site concentration catalyzes DME formation, while the presence of Cu+ species is crucial for DMM formation, and Cu0 species mainly catalyze MF formation. A highly dynamic reaction behaviour is observed, when the dehydrogenative functionality is dominant (i. e., in the production of MF or DMM), presumably due to the dynamic nature of the Cu oxidation state, which is in turn influenced by possible by‐products (H2 and H2O). While the catalytic activity in DME synthesis over 0.5 %Cu/Hβ(25) is remarkably stable over 1500 min TOS, the activity in MF and DMM production over 20 %Cu/Hβ(520) and 0.5 %Cu/Hβ(520), respectively, can be successfully regenerated.

Promoted catalytic performance of sugarcane bagasse ash supported by γ‐alumina as efficient, stable, and ecofriendly catalyst for dehydration of methanol to dimethyl ether

AbstractThe aim of this study was to use different proportions (1% to 20% by weight) of γ‐alumina to modify sugarcane bagasse ash (SCBA) for the production of dimethyl ether (DME) through the dehydration of methyl alcohol. A simple precipitation method was utilized to fabricate (1–20 wt.%) Al2O3/SCBA catalysts. X‐ray fluorescence, X‐ray diffraction, Fourier‐transform infrared spectroscopy, transmission electron microscopy, and N2 sorption were used to explore the structural, spectroscopic, morphological, and textural features. The XRD pattern of Al2O3/SCBA catalysts showed a new peak that corresponded to the formation of γ‐Al2O3. In addition, the average crystallite sizes of pure SCBA and 10% and 20%Al2O3/SCBA catalysts were calculated and found to be 20.1, 21.6, and 22.6 nm, respectively. To evaluate the acidity of these catalysts, the dehydration of isopropyl alcohol and the chemisorption of basic probe molecules were employed. The acidity test results displayed that these catalysts have weak to moderate acidic sites. The 10% Al2O3/SCBA catalyst calcined at 400°C showed high efficiency for the conversion of methyl alcohol to DME, attaining 89% conversion with 100% selectivity. This observation can be attributed to the even distribution of active sites and the acid–base equilibrium on the surface. Moreover, its catalytic activity and selectivity remain unchanged over a continuous 2‐week operation without coke formation, demonstrating its extremely high stability. A strong correlation was observed between the catalytic activity and both the surface area and acidity of the catalysts.

Development of a laboratory unit and a solid fuel gasification reactor

The paper investigates the process of gasification of pyrolysis coal and other coal-containing materials A schematic diagram of the installation of the gasification process of pyrolysis coal and other coal-containing materials was developed, the design of the reactor for coal gasification and the methodology for conducting experiments and analysing the gasification process of pyrolysis coal and other coal-containing materials were developed. Research methods - modelling of the coal gasification process using the results of theoretical studies. A detailed analysis of the experimental and theoretical data concerning the feasibility of the pyrolysis coal gasification process was carried out, a schematic diagram of the laboratory installation and the design of the gasification reactor were developed. The main goal is to develop a method of gasification of solid pulverised fuel that will simplify the process control and ensure its stability due to the unity of the drying and gasification processes of pyrolysis coal, which are linked by means of a gasification reactor. Additionally, this method provides for the neutralisation of harmful impurities generated during the coal gasification process. As a result of theoretical studies of the solid fuel gasification process, a design of a coal gasification reactor was proposed, which is an ideal displacement reactor. The length-diameter ratio for the working part of the reactor should be at least 10:1. It is proposed to use a heat-resistant molybdenum steel tube (operating temperature up to 1600 0C) with a diameter of two inches to manufacture the reactor. Also, to study the gasification process of pyrolysis coal and other coal-containing materials, a laboratory installation for gasification of solid crushed fuel is proposed, in which a gas mixture of carbon dioxide and oxygen is fed into the reactor and serves as an activator of the gasification process. The prospects of coal processing by gasification to produce a mixture of combustible gases (H2, CO, CH4) are investigated. It is analysed that coal gasification allows obtaining valuable gas that can be used not only as an energy fuel, but also as a technological raw material for the production of methanol, dimethyl ether, hydrogen production, and use as a reducing agent in metallurgical processes.

Process design and downstream optimization of the direct synthesis route for cleaner production of dimethyl ether from biogas

This study investigates an innovative method to produce dimethyl ether (DME) by direct synthesis from syngas derived from biogas. The proposed process was rigorously simulated in Aspen Plus, highlighting the main sections: (i) biogas tri-reforming, (ii) dimethyl-ether synthesis, and (iii) DME purification. The tri-reforming section has a CO2 and CH4 conversion of 27.3% and 96.2%, respectively A novel catalyst suitable for CO2-rich feed was chosen for the DME production to allow 60% conversion of CO2. Product separation is achieved via several absorption and distillation columns, ensuring that the operating conditions are kept mild to avoid expensive refrigeration. An optimization analysis was performed to identify the most suitable layout of the downstream process. This was identified through the evaluation of performance indicators such as utility usage and operating expenses. A wide range of purification strategies have been evaluated, and two scenarios are proposed based on the results. Configuration A produces 5.34 ktpy DME and 1.26 ktpy methanol, while Configuration B produces exclusively 6.21 ktpy DME. The process configurations were analysed by means of key techno-economic indicators and sustainability metrics. Both processes have an energy intensity of 14.5 kWh/kg. The reforming unit has a negligible footprint as it is thermally sustained from biogas combustion, but the reboilers are the main contributors for plant CO2 emissions. Configuration B has the best economic value with 11,634 k€ of NPV after 25 years and a payback time of 4 years.

Zirconia–sugarcane bagasse fly ash as a novel solid acid nanocatalyst for selective dehydration of methanol to dimethyl ether

AbstractIn the current study, two series of catalysts were synthesized and characterized by various physicochemical techniques. In the first series of catalysts, a chemical precipitation method was used for loading 1–20 wt. % ZrO2 on the surface of sugarcane bagasse fly ash (SCBFA) with the goal of finding out the optimal ZrO2 loading. In the second series, the 20% ZrO2/SCBFA composition was modified by (1–10 wt. %) SO42− by wet impregnation method. The acidity of these catalysts was determined through the dehydration of isopropyl alcohol and the chemisorption of pyridine and 2,6‐dimethyl pyridine. The catalytic efficiency for the dehydration of methanol to dimethyl ether (DME) in a fixed‐bed reactor at atmospheric pressure was investigated. A ~ 95% yield toward DME is maximized over the 10% SO42−/20% ZrO2/SCBFA catalyst at a reaction temperature of 400°C. Additionally, it maintained nearly the same efficiency over a 90‐h period and demonstrated outstanding long‐term stability. The specific surface area and the acidity are the most important factors responsible for enhancing the catalytic performance in this reaction. Our study reflects that SCBFA‐supported zirconia and that modified with SO42− are low‐cost, effective, eco‐friendly, and recyclable catalysts that are highly suited to apply for production of DME from methanol.

Narrative Policy Analysis: Utilization of Dimethyl Ether as an LPG Mixed Fuel (Case Study in Indonesia)

Dimethyl Ether (DME) utilization as an LPG fuel mix policy has become a polemic among several groups. The purpose of this research is to analyze the effectiveness of narrative constructed by Government, analyze the counter narrative, and formulate a strategy to strengthen the Government narrative regarding the use of DME as an LPG mixed fuel. This research uses the Narrative Policy Analysis (NPA) method. The counter narrative is compared with Government narrative to obtain a meta narrative. The level of analysis in this research is meso. The conclusions from this research are: 1) Indonesia Government continues to use DME as a mixed fuel for LPG; 2) The obstacles of policy narrative constructed by the Indonesia Government are differences viewpoints regarding the availability and use of coal as raw material for DME and differences in belief system regarding greenhouse gas emissions. The recommended strategy to strengthen the Government’s policy narrative are: 1) Comprehensive discussion by involving groups that oppose the narrative, 2) present the result of the feasibility study on greenhouse gas emmision resulting fro DME production process from coal which has been carried out by the Government by providing socialization regarding tax policy carbon as well as technical implementation of carbon economic value and controlling greenhouse gas emmision.