Production Of Liquid Hydrocarbon Fuels Research Articles

Production of liquid hydrocarbon fuels through catalytic cracking of high and low-density polyethylene medical wastes using fly ash as a catalyst

This study explores the potential of converting High-Density Polyethylene (HDPE) and Low-Density Polyethylene (LDPE) waste into liquid hydrocarbon fuels through catalytic degradation using fly ash. It achieves significant conversion rates, with HDPE reaching over 95% total conversion and a 66.4% oil yield at a catalyst-to-polymer ratio of 0.20, while LDPE shows a 100% conversion rate at ratios of 0.15 and 0.20. The process not only yields hydrocarbons with decreasing density and increasing calorific values, up to 55 MJ/kg for HDPE and 47 MJ/kg for LDPE at optimal conditions but also produces fractions with properties similar to diesel, notably in terms of density and viscosity. The flashpoint and fire point values further affirm these products' potential as viable fuel sources, aligning closely with diesel standards. 1H NMR spectroscopy analysis reveals a composition rich in long-chain alkanes and alkenes, indicating the efficient transformation of plastic waste into valuable energy resources. This research presents a promising avenue for recycling plastic waste into alternative fuels, highlighting a sustainable approach to waste management and energy recovery.

Enhancing the methanol yield of industrial-scale fixed bed reactors using computational fluid dynamics models

Achieving our decarbonisation goals for the maritime transport sector requires the bulk production of liquid hydrocarbon fuels, suitable for the existing infrastructure, such as methanol (MeOH). For this, optimisation of fixed bed chemical reactors is vital. Unlike demonstration-scale setups, optimising the design of such reactors using Computational Fluid Dynamics (CFD) models is both cheaper and faster. In this study, using a 2D pseudo-homogeneous CFD model, a single tube from a multi-tubular industrial-scale MeOH reactor is simulated. Using available experimental data, the CFD model was validated yielding excellent accuracy, with an average error of 2.6 %. The model identified a temperature hot-spot near the bed entrance, while the predicted pressure drop was 11 % of the operating pressure. Both effects could considerably reduce the efficiency of the reactor, either by catalyst deactivation or by increasing the compressor requirements, respectively. Through a parametric study where the tube’s length and diameter were varied within the ±50 % range, 53 total cases are produced and solved, creating an extensive pareto set of data for the key output parameters, such as methanol production, pressure, and temperature. A response surface was also generated, revealing the interconnection between the tube’s design and the operating parameters. This enabled a performance optimisation of the reactor design for two industrially relevant scenarios, with the optimised reactor achieving a 6.9 % higher MeOH yield and a 75 % reduced pressure drop. Through industrial involvement, the reactor can be further optimised, and would act as a critical foundation for more extensive techno-economic and socio-economic evaluations for sustainable carbon–neutral methanol production.

Innovative parallel synthesis of 5-nonanone and furfural from lignocellulosic biomass accompanied by deep economic analysis

An integrated strategy is developed to utilize all three primary components (cellulose, hemicellulose, and lignin) of lignocellulosic biomass for the coproduction of hydrocarbon fuel (5-nonanone) and bio-chemicals (furfural and high purity lignin). After biomass fractionation, (1) 5-nonanone is produced with high yield of 89% using cellulose-derived γ-valerolactone (GVL), which can potentially serve as a platform molecule for the production of liquid hydrocarbon fuels for the transportation sector; (2) furfural, a valuable platform chemical, is produced using hemicellulose; and (3) production of high-purity lignin, which can be used to produce carbon foams or battery anodes. Separation subsystems are designed to effectively recover the solvents for reuse in the conversion processes, which ultimately improves the economic feasibility of the integrated process, resulting in achieving lower minimum selling price (MSP) of $5.47 GGE-1 for 5-nonanone compared to market price. Heat pump is introduced to perform heat integration, which reduces utility requirements more than 85%. Finally, a wide range of techno-economic analysis is performed to highlight the major cost and technological drivers of the integrated process.

Performance evaluation, Optimization and exergy analysis of a high temperature co‐electrolysis power to gas process using Aspen Plus®‐a model based study

AbstractIn this paper, a high temperature coelectrolysis power to gas (LTE PtG) setup was developed that was fed a stereotypical feed in CO2 one could acquire from carbon capture and sequestration (CCS) retrofit. The electrolyzer was fed an equimolar 10 kmol/s feed in water and CO2 and the electrolyzer product was composed of 38.80 mole% CO2, 30.96 mole% CO, and 30.24 mole% H2 for a syngas conversion of 43.8%. The product from the methanation unit was only composed of 21.38 mole% CH4, with the rest (76.53 mole%) being predominantly CO2. The methanation unit was composed of only one Sabatier reactor operating at 313°C, which had 90% of its product recycled back to the front end of the unit. The electrolyzer was found to have a LHV efficiency of 31.49%, and the entire HTCE PtG process was found to have an efficiency of 74.31% with methane storage and 76.49% without methane storage. A novel adaptation was developed on previous work on the exergy analysis for flow‐sheet simulators which can be used for cyclic and noncyclic processes. The procedure was determined to be accurate, with irreversibilities determined across all the major subunits found to equal the irreversibility around the processes a whole. The electrolyzer was found to be responsible for the majority of the irreversibility within the setup, and this was attributed to the fact that water electrolysis is a very energy intensive process. The exergy efficiency of the electrolyzer was found to be 87.07% and that of the entire LTE PtG processes was found to be 84% with methane storage, and 87% without methane storage. In the end, it was determined that HTCE is unsuitable for the production of methane via retrofit with a methanation unit, and that it would be better suited for the production of liquid hydrocarbon fuels with much higher molecular carbon to hydrogen ratios.

(Invited) Increasing Biogas to Liquid Fuel Yield By Solid Oxide Co-Electrolysis of Biogas CO2 Fraction

OxEon Energy, LLC (OxEon) plans to demonstrate production of liquid hydrocarbon fuels using both the methane and CO2 generated in a food waste digester operated by the Environmental Products & Technologies Corporation (EPT). The EPT food waste digester in Burley Idaho sells produced biogas into a natural gas pipeline after separating and venting the bio-CO2. This project will convert the bio-methane to synthesis gas (syngas, as CO & H2) using a non-thermal plasma catalyzed autothermal reformer. To achieve high bio-carbon utilization, an OxEon high temperature solid oxide co-electrolysis (HTCE) system will electrochemically generate additional syngas from the bio-CO2 combined with steam raised by cooling the Fischer Tropsch (FT) reactor. Syngas from the reformed methane and co-electrolyzed CO2, will be converted to liquid fuels using an OxEon developed FT reactor. Each of the technology components have been field tested independently and will be combined for the first time in this project. The project outcome will be an engineering scale demonstration of liquid hydrocarbon bio-fuel production achieving > 50% conversion to liquids of the biogenic carbon in both CH4 & CO2 produced by an anaerobic digester.Each of the three technology elements of the integrated engineering test incorporates numerous innovations. The plasma reactor is designed to be fuel flexible, sulfur tolerant, and economically scalable to small, distributed bio-gas resources. It is also very efficient using a low power non- thermal plasma. High temperature solid oxide electrolysis has demonstrated efficiency at the thermodynamic limit as shown by analysis and testing at DOE and NASA laboratories, and is unique in its ability to co-electrolyze steam and CO2 directly to syngas. The HTCE stacks use innovations proven for the NASA Mars 2020 project which required exceptional ruggedness and effective high temperature seals. The FT reactor enables economical fabrication of smaller size synthetic fuel plants designed to match the scale of distributed renewable biomass resources. This is achieved with large diameter standard piping combined with a novel internal thermal management structure.The status of the technology elements and the planned engineering demonstration will be presented.This work is supported by the Bioenergy Technologies Office of the US Department of Energy.

Phosphorus‐Modified Mesoporous Inorganic Materials for Production of Hydrocarbon Fuels and Value‐Added Chemicals

AbstractPhosphorus‐modified mesoporous inorganic materials play crucial roles in the valorization of lignocellulosic biomass materials such as syngas (CO and H2), carbohydrate sugars and lignin. This review summarizes the recent advances on the Co‐impregnated phosphorus‐modified γ‐Al2O3 and SiO2 catalysts for production of liquid hydrocarbon fuels via Fischer‐Tropsch synthesis (FTS) reaction of syngas as well as metal phosphates or precious (Pt and Ru) metals‐supported on the metal phosphates for production of furanic compounds, levulinic acid, aromatics and fuel commodities from carbohydrate sugars and lignin. These phosphorus‐modified materials play key roles in the syngas as well as biomass conversion processes due to their tunable surface properties and mesoporous structures. Phosphorus to metal ratios of inorganic materials with their porosity, calcination temperatures of metal phosphates, natures of biomass feedstocks, and reaction variables significantly affect yields of both hydrocarbon fuels and value‐added chemicals. This short review mainly focusses on the various applications of those mesoporous catalysts and supports, and strategies for effective catalytic transformations of lignocellulosic biomass‐derived feedstocks.

Catalytic cracking of rubber seed oil using basic mesoporous molecular sieves K2O/MeO-SBA-15 (Me = Ca, Mg or Ba) as heterogeneous catalysts for the production of liquid hydrocarbon fuels

Liquid hydrocarbon fuels obtained from the catalytic cracking animal fats and plant oils have become one kinds of the attractive fuels because of their possible environment benefits and the current concern over the depletion of fossil fuel sources. In this work, using the combined methods of one-pot synthesis and wetness-impregnation, some basic mesoporous molecular sieves K2O/MeO-SBA-15 (Me = Ca, Mg or Ba) were prepared, characterized and used in the catalytic cracking of rubber seed oil (RSO). The results indicated that the catalysts K2O/MeO-SBA-15 had better catalytic performances than MeO-SBA-15, assigning to their stronger basicity. The catalyst K2O/MgO-SBA-15 obtained with 15 wt% KNO3 impregnation concentration showed the excellent catalytic performance with about 93.2% conversion and 78.3% yield of liquid hydrocarbon biofuel. The obtained liquid biofuel had similar chemical composition to diesel-based fuels and showed good cold flow property, high calorific and low acid value. Importantly, the catalyst K2O/MgO-SBA-15 was of excellent reusability, and it was reused with negligible loss in its catalytic performance for five times, attributing to the MgO layer between silicon skeleton and potassium species which prevents the reaction between silicon in the framework and potassium species.

Extending the basic function of lattice oxygen in lepidocrocite titanate – The conversion of intercalated fatty acid to liquid hydrocarbon fuels

We report herein the basicity of the external and internal lattice oxygen (OL) in lepidocrocite titanates with respect to CO2 and palmitic acid, respectively. Several compositions have been tested with different types of the metal M aliovalently (co)substituted for Ti, K0.8[MyTi2−y]O4 (M = Li, Mg, Fe, Co, Ni, Cu, Zn, Cu/Ni and Cu/Zn). The low CO2 desorption peak temperature (70–100°C) suggests that the external OL sites are weakly basic similar to TiO2. However, the internal OL sites are sufficiently basic to deprotonate palmitic acid, forming the intercalated potassium palmitate at the interlayer spaces. The latter serves as a two-dimensional (2D) molecular reactor for the production of liquid hydrocarbon fuels via deoxygenation under atmospheric N2. A relationship has been observed between the yield of the liquid products vs the partial charge of the lattice oxygen (δO). Since the deoxygenation pathway is highly dependent on the metal substitution, the redox-active sites might also play some roles. The co-substituted K0.8[Cu0.2Ni0.2]Ti1.6O4 produced ~68.0% yield of the liquid products, with ~ 51% saturated and ~ 15% unsaturated C15 hydrocarbons at 350°C.

Extremum Seeking Control of Carbon Monoxide Concentration in Underground Coal Gasification

Coal gasification is a promising option for the future use of coal. Similarly to gasification in industrial reactors, underground coal gasification (UCG) produces syngas, which can be used for power generation or for the production of liquid hydrocarbon fuels and other valuable chemical products. As compared with conventional mining and surface gasification, UCG promises lower capital operating costs and also has other advantages, such as no human labour underground. The main goal of the study presented in the paper was to experimentally demonstrate the structure of optimal control system of lignite underground gasification which consists from stabilization and optimization level. This paper proposes an alternative extremum seeking control design technique for the solution of real-time optimization control problems in UCG by aim to maximize a content CO in syngas.

Catalytic co-pyrolysis of torrefied yellow poplar and high-density polyethylene using microporous HZSM-5 and mesoporous Al-MCM-41 catalysts

The catalytic pyrolysis of lignocellulosic biomass with aluminosilicate catalysts is a promising method for the direct production of liquid hydrocarbon fuels consisting mainly of aromatic compounds (e.g., benzene, toluene, and xylenes). On the other hand, the economic and commercial viability of this process is limited by the low yields of aromatic hydrocarbons. In this study, the effects of biomass torrefaction, co-feeding of plastic wastes, their combination, and the catalytic upgrading mode (in-situ vs ex-situ) on the aromatic formation efficiency during the catalytic pyrolysis of yellow poplar were evaluated systematically to maximize the production of aromatic hydrocarbons. Two representative catalysts for catalytic pyrolysis (i.e., microporous HZSM-5 and mesoporous Al-MCM-41) were used in this case study. The torrefaction of yellow poplar led to the enhanced production of aromatic hydrocarbons in the catalytic co-pyrolysis of yellow poplar and high-density polyethylene over both catalysts. The experimental yields of aromatic hydrocarbons from the catalytic co-pyrolysis of torrefied yellow poplar and high-density polyethylene were also higher than their theoretical yields, highlighting the synergistic aromatic formation by the interaction of torrefied yellow poplar and high-density polyethylene. Between the two catalysts, microporous HZSM-5 exhibited much higher activity for aromatic production from catalytic co-pyrolysis owing to its strong acidity and appropriate pore structure. Compared to ex-situ catalytic co-pyrolysis, the in-situ catalytic co-pyrolysis of torrefied yellow poplar and high-density polyethylene produced larger amounts of aromatic hydrocarbons due to the more effective contact between the pyrolysis vapors and HZSM-5.

Process synthesis and analysis for catalytic conversion of lignocellulosic biomass to fuels: Separate conversion of cellulose and hemicellulose using 2-sec-butylphenol (SBP) solvent

We developed a strategy for the catalytic production of liquid hydrocarbon fuels (butene oligomers) from cellulose and hemicellulose, which are the major fractions of lignocellulosic biomass. In this strategy the cellulose and hemicellulose fractions are separated through a pretreatment step and then converted to levulinic acid (LA) by monophasic and biphasic reactions using 2-sec-butylphenol (SBP) solvent respectively. The LA is upgraded catalytically to γ-valerolactone (GVL), and subsequently to butene oligomers. To design the integrated strategy, we developed separation subsystems to satisfy the optimized feed concentration for catalytic conversions and to recycle solvents (SBP). To satisfy energy requirements for our process from combustion of biomass residues, we designed a heat exchanger network (HEN) for minimum energy consumption by maximizing heat recovery from the process streams. Our technoeconomic evaluation shows that the integrated strategy using corn stover feedstock results in a minimum selling price of $3.71 per gallon of gasoline equivalent for butene oligomers if using the best possible parameters.

Production of liquid hydrocarbon fuels with acetoin and platform molecules derived from lignocellulose

Acetoin, a novel C4 platform molecule derived from a new ABE fermentation system was used as a bio-based building block for the production of liquid hydrocarbon fuels.

Production of liquid hydrocarbon fuels with 3-pentanone and platform molecules derived from lignocellulose

Diesel or jet fuel range C10–C17 branched and cyclic alkanes were produced by reaction of 3-pentanone derived from lactic acid with bio-based aldehydes.

Liquid hydrocarbon fuels from catalytic cracking of rubber seed oil using USY as catalyst

The catalytic cracking of rubber seed oil (RSO) to produce liquid hydrocarbon fuels using USY (ultrastable Y zeolite) as a heterogeneous catalyst has been studied. Under the optimum cracking conditions of RSO 10g, m(USY)/m(RSO)=1:50, and 420°C for 90min, the yield of liquid product reached 75.6%, and the chemical composition and properties of the liquid fuel were similar to those of gasoline-based fuels (C8–C9 content >70%, low acid value, good cold-flow properties, and high calorific value). The stability of USY has been studied, and the results showed that it could be reused with negligible loss of activity over at least six cycles. USY appears to be a suitable heterogeneous catalyst for the production of liquid hydrocarbon fuels from RSO.

Kinetics of hydrodeoxygenation of stearic acid using supported nickel catalysts: Effects of supports

The hydrodeoxygenation of fatty acids derived from vegetable and microalgal oils is a novel process for production of liquid hydrocarbon fuels well-suited with existing internal combustion engines. The hydrodeoxygenation of stearic acid was investigated in a high pressure batch reactor using n-dodecane as solvent over nickel metal catalysts supported on SiO2, γ-Al2O3, and HZSM-5 in the temperature range of 533–563K. Several supported nickel oxide catalysts with nickel loading up to 25wt.% were prepared by incipient wetness impregnation method and reduced using hydrogen. The catalysts were then characterized by BET, TPR, H2 pulse chemisorption, TPD, XRD, and ICP-AES. Characterization studies revealed that only dispersed nickel oxide was present up to 15wt.% nickel loading on γ-Al2O3. The acidity of the supports depends on nickel loading of oxidized catalysts and increases with increasing nickel loading up to 15wt.%. n-Pentadecane, n-hexadecane, n-heptadecane, n-octadecane, and l-octadecanol were identified as products of hydrodeoxygenation of stearic acid with n-heptadecane being primary product. The catalytic activity and selectivity to products for hydrodeoxygenation of stearic acid depends strongly on acidity of the supports. The maximum selectivity to n-heptadecane was observed with nickel supported γ-Al2O3 catalyst. A suitable reaction mechanism of hydrodeoxygenation of stearic acid was delineated based on products distribution. The conversion of stearic acid was increased with increasing reaction time, nickel loading on γ-Al2O3, temperature, and catalyst loading. Complete conversion of stearic acid was accomplished with more than 80% selectivity to n-heptadecane at reasonable reaction temperature of 563K after 240min of reaction using 15wt.% Ni/γ-Al2O3 catalyst. An empirical kinetic model was also developed to correlate the experimental data.

Liquid Hydrocarbon Fuels from Catalytic Cracking of Waste Cooking Oils Using Basic Mesoporous Molecular Sieves K2O/Ba-MCM-41 as Catalysts

Mesoporous molecular sieves K2O/Ba-MCM-41, which feature base sites, were prepared under hydrothermal conditions. The structure, base properties, and catalytic activity of the mesoporous molecular sieves as heterogeneous catalysts for the cracking of waste cooking oil (WCO) were then studied in detail. K2O/Ba-MCM-41 exhibited higher catalytic performance for the cracking of WCO than traditional base catalysts such as Na2CO3 and K2CO3. Moreover, the cracking of WCO generates fuels (main composition is C12∼C17 alkane or olefin) that have similar chemical compositions to diesel-based fuels, and K2O/Ba-MCM-41 is of excellent stability. The catalyst could be recycled and reused with negligible loss in activity for four cycles. K2O/Ba-MCM-41 is an environmentally benign heterogeneous basic catalyst for the production of liquid hydrocarbon fuels from low quality feed stocks.

Mesoporous molecular sieves K2O/Ba(Ca or Mg)-MCM-41 with base sites as heterogeneous catalysts for the production of liquid hydrocarbon fuel from catalytic cracking of rubber seed oil

Mesoporous molecular sieves K2O/Ba(Ca or Mg)-MCM-41, which feature basic sites, were prepared by the coordination effect of ion exchange and impregnation method under hydrothermal conditions, and used as heterogeneous catalysts for the cracking of rubber seed oil (RSO). The structure, base properties and catalytic performance were then studied in detail. The K2O/Ba(Ca or Mg)-MCM-41 exhibited higher catalytic performance than traditional base catalysts such as Na2CO3 and K2CO3. Moreover, the fuels generated from the cracking of RSO have similar chemical compositions to diesel-based fuels and low acid values. The cracking products with low acid values showed good cold flow properties, calorific values and good solubility in diesel oil at low temperature. At the same time, the K2O/Ba(Ca or Mg)-MCM-41 has excellent stability. The catalyst could be recycled and reused with negligible loss in activity over six cycles. The K2O/Ba(Ca or Mg)-MCM-41 is base- and water-tolerant and is an environmentally benign heterogeneous catalyst for the production of liquid hydrocarbon fuels from low quality feed stocks.

A sulfuric acid management strategy for the production of liquid hydrocarbon fuels via catalytic conversion of biomass-derived levulinic acid

In this study, we first develop an integrated strategy for the catalytic conversion of lignocellulose into liquid fuels based on the production of levulinic acid (LA) followed by its hydrogenation to γ-valerolactone (GVL). Our integrated strategy involves a novel catalytic conversion process employing alkylphenol-based separation to extract LA from the sulfuric acid containing aqueous solution following the sulfuric acid catalyzed deconstruction of cellulose. To minimize utility consumption, we perform heat integration, while the remaining heating requirement is satisfied by the combustion of residual biomass. Hot combustion gases are also used to generate electricity, which meets the electricity requirement of the process, while the excess electricity is sold to the grid. We perform a technoeconomic analysis for the alkylphenol-based strategy and compare its economics with a previously reported strategy, in which butyl acetate was used as an extractive solvent to separate GVL from sulfuric acid following the LA hydrogenation step. With some improvements in the process configuration, the alkylphenol strategy leads to a minimum selling price (MSP) of $4.40 per gallon of gasoline equivalent (GGE) for compatible biofuel components, whereas the butyl acetate strategy leads to a MSP of $4.68 per GGE. We show that the alkylphenol strategy becomes a significantly better choice when the catalyst lifetime for the hydrogenation of LA becomes less than 6 months.

Production of liquid hydrocarbon fuels by catalytic conversion of biomass-derived levulinic acid

Levulinic acid derived from ligno-cellulosic biomass has the potential to be utilized as a platform intermediate molecule in the production of renewable liquid fuels for the transportation sector. Herein we report a catalytic process for the conversion of levulinic acid to γ-valerolactone (GVL) using a RuRe/C catalyst that is significantly more active than a traditional Ru/C catalyst. The bimetallic catalyst is active for the reduction of levulinic acid and simultaneous decomposition of formic acid with good stability in the presence of sulfuric acid, the homogeneous catalyst commonly used in the production of levulinic acid from carbohydrates. Results from techno-economic analyses show that the integration of this new process with catalytic decarboxylation of GVL to butene followed by alkene oligomerization could provide a cost-effective route for the conversion of ligno-cellulosic biomass to liquid hydrocarbon fuels.

Techno-economic analysis of 5-nonanone production from levulinic acid

We analyze a process for production of 5-nonanone (dibutyl ketone, DBK) from levulinic acid (LA) which is a biobased platform chemical that can be produced in large quantities from a variety of lignocellulosic biomass sources. The techno-economic analysis is based on a catalytic pathway developed in lab scale. The final product (DBK) has applications as an industrial solvent and serves as a platform chemical for the production of liquid hydrocarbon fuels in the diesel and gasoline ranges. A detailed process model has been created for two different product purity levels (90% and 99%). Process economics have been studied in a discounted cash flow analysis to analyze the viability of production and relative product purification costs. The modeled process utilizes 480 metric ton/day of LA feedstock to produce 194 metric ton/day of DBK along with other by-products. Sensitivity analysis is used to identify the impact of key parameters on the minimum selling price of product. Thus, the price of the feedstock (LA) and the DBK final yield were found to be the most sensitive parameters affecting the final price of the product. With the current LA market price ($3.2 per kg) and the experimental yield of 66%, the minimum selling price estimated for a high purity DBK was $8.5 per kg, comparable to the current DBK purchase price ($9.07 per kg) but still quite high compared to the price of a typical petroleum-derived solvent such as methyl ethyl ketone ($0.77 per kg). Further improvements on the lab scale to increase the yield of DBK, and the use of inexpensive LA from the patented Biofine process, would allow the production of DBK at competitive prices for chemical and fuel applications.