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Green and efficient routes for a sustainable and renewable strategy in chemicals and energy delivery are highly demanded in the current status. Developing production routes from bio-alcohols is of immense interest. To achieve such a goal, an enhanced membrane-assisted dehydration reactor for the conversion of bio-alcohols (mainly made up of methanol and ethanol) is suggested. The system can eliminate the innate and produced water through the dehydration reaction, representing an intensified process that favors a conversion enhancement without needing a water purification unit. This study includes a rigorous feasibility study utilizing a validated mathematical model. The impacts of input variables such as feed flowrate, feed temperature, feed composition, and feed pressure, as well as the sweep gas flowrate and temperature, are examined. The sensitivity analysis is conducted in terms of feed conversion, temperature profiles, pressure drop, and desired product distributions. Then, an optimization strategy was developed to obtain the optimum operating conditions of each system leading to maximized conversion and product yields. According to the achievements of this study, the enhanced membrane-assisted dehydration reactor offers a great capacity for converting bio-alcohols and producing considerable quantities of DME from bio-methanol as well as DEE, ethylene, and butylene from bio-ethanol.

Owing to the necessity of carbon dioxide conversion and exploring new routes for ethylene and hydrogen production, carbon-dioxide-assisted dehydrogenation over alumina-supported catalysts is evaluated in the present contribution. In this regard, the experimental results of a wide range of catalysts at 700 °C and the GHSV of 3600 Lreactants/kgcatalyst.hr are presented and compared. The utilized catalysts showed activity toward the conversion of ethane. However, a few of them showed good selectivity for the production of either ethylene or hydrogen. The catalysts made up of the oxides of cobalt and molybdenum showed very good conversion, selectivity, and yield for ethylene production. Investigating the effect of time on steam on the catalyst performance indicated that these catalysts would be suitable choices in the course of ethylene production. 58% conversion of ethane and 21.9% ethylene yield are the achievements of utilizing the molybdenum-cobalt oxide catalyst. By utilizing rhenium-platinum nickel-potassium catalysts, 100% ethane conversion in tandem with more than 260.0% hydrogen yield was also obtained.

Developing biomass-based strategies for liquid bio-fuels production is promising for the reduction of the aftereffects of fossil fuels. The conversion of lignin-derived intermediates such as cyclohexanone is currently of a great deal of interest. The current study aims to evaluate the molybdenum-based hydrotreating catalysts for the conversion of cyclohexanone in the presence of hydrogen. Catalytic experiments at 400 °C, 15 bar, and a range of WHSV were developed. The experiments reveal that catalyst type and reaction WHSV affect the cyclohexanone conversion, product distribution, deoxygenation efficiency, total hydrocarbon production capacity, and heating value of the product blend. The main products include C6 cyclic and aromatic hydrocarbons and oxygenates. Cyclohexane, cyclohexene, benzene, cyclohexanol, and phenol are major products. Small quantities of methylcyclopentane and bicyclic hydrocarbons and oxygenates are also reported in some cases. Increasing WHSV reduced the cyclohexanone conversion. Cyclohexanone conversions up to 89% were observed at the lowest WHSVs over a cobalt-molybdenum sample. The highest hydrocarbon production capacity (99.53%) was managed at WHSV = 5.240 gcyclohexanone/gcat h over a cobalt-molybdenum sample, while the highest deoxygenation efficiency, i.e. 81.29% degree of deoxygenation and 5.35 C/O ratio enhancement were achieved at WHSV = 0.262 gcyclohexanone/gcat h by a nickel-molybdenum sample. The heating values would be enhanced by up to 22.7% when cyclohexanone is converted over the utilized catalysts. The larger heating value (44.90 MJ/kg, 22.7% enhancement) was obtained over a nickel-molybdenum catalyst, which is comparable to the energy density of the conventional fuels. The results reveal that the catalysts are efficient in the conversion of cyclohexanone to liquid bio-fuels.

Developing simple theoretical models that are capable of estimating the physical properties of nanofluids such as viscosity in a broad range is currently a major trend. Following this necessity, the present contribution is devoted to applying the free-volume model for the calculation of nanofluids’ viscosity. To do so, the combination of the free-volume model and the Esmaeilzadeh–Roshanfekr equation of state was applied. A simple modification was also developed to enhance the performance of the model. Results were additionally compared with the empirical equations extracted from the literature. In this regard, a broad data bank including 932 experimental viscosity data of various nanofluids was gathered. The collected nanofluids include different base fluids (water, methanol, ethylene glycol, and propylene glycol) and various nanoparticles [Al2O3, SiO2, TiO2, Ag, Fe, ZnO, MgO, and functionalized multiwalled nanotube (FMWNT)]. The overall errors in calculations (AARD%) for 26 nanofluids are 19.83% and 2.99% for the original and modified models, respectively. The R-squared values are 0.14 and 0.99 for the original and modified models, respectively, revealing the superiority of the modified model. The largest deviations of the modified model were found to be 8.25% and 6.47% for ethylene glycol/MgO and water/ZnO systems, respectively. A comparison of the modified model developed in the present study with the empirical models of the literature revealed that the modified model results in an 11.3–16.4% improvement of the precision of nanofluids viscosity calculations.

Cyclohexanone is largely generated in the direct or indirect conversion of lignin-derived bio-oils. Hence, the upgrading of cyclohexanone, i.e. deoxygenation in the presence of hydrogen is of great interest. In this regard, two nickel-molybdenum catalysts on alumina support were investigated in the temperatures up to 400 °C and pressures up to 15 bar. High activity, selectivity, and yield were achieved by utilizing these catalysts at the studied condition. The main products of the upgrading of cyclohexanone were C6, C7, and C12 cyclic, aromatic, and bicyclic including cyclohexane, cyclohexene, benzene, and cyclohexylbenzene. The results of the present study imply that these catalysts are beneficial in producing hydrocarbon-rich products from cyclohexanone and lignin-derived bio-oils. Based on the achievements of the present study, the nickel-molybdenum catalyst composed of 1.14 wt% nickel and 14.27 wt% molybdenum showed about 87%, 100%, and 116% conversion of cyclohexanone, total hydrocarbon selectivity, and total hydrocarbon yield, respectively. The optimum condition for obtaining such results was at 400 °C and 8 bar.

The push to control the greenhouse gas emissions is motivated by environmental regulations. For the aim to be achieved, the suggestion of eliminating or at least reducing gas flaring is currently taken under environment. In this regard, a new configuration for flare gas treatment is proposed in this study. This configuration is aimed to collect H2 and CO2 from flare gas, simultaneously. The collected components would be sent to the methanol synthesis reactor in the upstream section. The proposed configuration is made up of a multi-step membrane-assisted separation unit. In order to clarify what lies behind the idea, we proposed a mathematical formulation which is composed of conservation equations and kinetic rate equations is developed. H2 and CO2 elimination in the first step followed by a membrane-assisted water gas shift reactor for catalytic CO conversion and H2 recovery in tandem, and removing the remaining CO2 in the supplementary step is investigated numerically. The collected H2/CO2 mixture is aimed to recover into the upstream methanol synthesis reactor. The obtained results reveal that by utilizing such a strategy, about 2500 kmol/day CO2 (almost 98% of total input) is eliminated from the flare gas stream. Moreover, by considering the converted CO, about 4050 kmol/day CO2 is recovered to the methanol reactor. As a whole, 0.68% enhancement in the methanol generation and the reduction of about 4050 kmol/day flare gas pollutants are achieved in tandem when 98% N2 and 92.9% CH4 is separated the from purge gas.

Following the importance of nanofluids (NFs) and their applications in heating/cooling sections of the industries, their thermophysical properties are investigated herein. In this regard, an extensive study of density, viscosity, and thermal conductivity is developed. The effects of temperature and nanoparticle characteristics (type, concentration, and size) are evaluated based on the experimental data of the literature. These factors affect the thermophysical properties strongly. Furthermore, the theoretical and neural network models for the estimation of properties are reviewed. Although various NFs are potential working fluids for heat transfer applications, their successful development on the commercial scale relies on their performance under practical conditions. However, the assessment of the thermophysical properties of NFs could pave a reliable path toward successful development on the commercial scale.

The present study provides a modified approach in determining gas adsorption equilibria based on two-dimensional equations of state (2-D EOS). The proposed model utilizes temperature-dependent parameters in the general form of the 2-D EOS. These parameters were considered similar to other well-known isotherm models, such as Langmuir as specifics function of temperature. The proposed model was examined against various experimental single- and multi-component adsorption isotherm data. In most of the investigated cases, the proposed model reduces the error of predictions compared with temperature-independent two-dimensional equations of state. Moreover, utilizing temperature-dependent two-dimensional equations of state, isosteric heat of adsorption was theoretically obtained and compared with experimental heats of adsorption for different homogeneous and heterogeneous adsorption systems. Applying temperature-dependent parameters within 2-D EOS enables us to describe the heterogeneity of considered adsorption systems quite well. Predicted isosteric heats are in good accordance with the experimental data.

Owing to the importance of process intensification in the natural gas associated processes, the present contribution aims to investigate the production of an important natural gas downstream product in an improved system. Accordingly, a membrane-assisted reactor for the oxidative dehydrogenation of ethane is presented. The presented system includes a membrane for axial oxygen dosing into the reaction side. Such a strategy would lead to optimum oxygen distribution along the reactor length and prevention of hot spot formation as well. A feasibility study is conducted by developing a validated mathematical model composed of mass and energy balance equations. The effects of various operating variables are investigated by a rigorous sensitivity analysis. Then, by applying the genetic algorithm, a multi-objective optimization procedure is implemented to obtain the optimum operating condition. Considerable increase in the ethane conversion and ethylene yield are the advancements of membrane-assisted oxidative dehydrogenation reactor working under the optimum condition. More than 30% increase in the ethane conversion is obtained. Furthermore, the ethylene yield is enhanced up to 0.45.

A two-step configuration consisting water-cooled and gas-cooled reactors has been developed by Lurgi to produce methanol from natural gas. The gas-cooled reactor, which is a vertical shell and tube heat exchanger, is constructed by fixed tube sheets with the cold gas stream in the tube side to properly cool the reacting gas mixture in the shell side. Under the practical operating condition, increase in the temperature drop is observed. As a result of high temperature decrease occurs at the end of the reactor, formation of gas condensate is observed in the fourth year of operation. In this regard, a computational fluid dynamics (CFD) model was developed to predict the behavior of gas streams in the shell and tube sides in order to find the reasons such phenomenea. The obtained results of the developed model were validated with the real plant data and a good agreement was observed. Then, gas velocity and temperature distributions in the shell and tube sides were presented. The obtained results show that the temperature mal-distribution in the shell side is a result of non-uniform flow distribution in the shell and tube sides. Furthermore, this flow distribution non-uniformity inside the reactor comes from an improper design of the distributer inside the reactor.

Following the importance of the conversion of lignin compounds into beneficial products, a new cleaner production strategy is proposed. To this end, simulated lignin-derived syngas was utilized instead of pure hydrogen for anisole and cyclohexanone conversion over a platinum catalyst. The experiments at 300–400 °C and 1–15 bar are addressed. The impact of weight hourly space velocity (WHSV) is also investigated. The new strategy offers high activity, selectivity, and yield for the conversion of anisole and cyclohexanone to possibly value-added products. Anisole conversion results in the formation of phenol, cyclohexanone, and methylated phenols. Cyclohexanone reaction produces cyclohexane, cyclohexene, benzene, cresols, phenol, and toluene. Increasing reaction temperature and pressure enhances the conversion of the reactants while increasing WHSV decreases the conversion. The highest anisole (87.44%) and cyclohexanone (77.02%) conversions were obtained at 400 °C, 15 bar, and the smallest WHSV. Temperature, pressure, and WHSV had major effects on the conversions and product distributions. The highest hydrocarbon yields and carbon-to-oxygen ratio enhancement (C/O RE) were managed at different conditions for anisole and cyclohexanone. The present study indicates that the new syngas-assisted strategy could be utilized for the conversion of lignin-derived compounds to hydrocarbons and possibly value-added products.

With the aim of investigating the solutions of ethane shortage in a commercial ethylene plant, addition of propane as supplementary feedstock and increasing steam to hydrocarbon ratio were proposed as possible strategies. These strategies were proposed to compensate for the ethane shortage in the thermal cracking unit of the commercial plant. Run length, ethylene yield, and propylene yield were considered as the determining factors to appraise the strategies. The major contribution of present work would be the investigation of effect of feed shift on the run length of the steam cracker. Regarding this, five different cases were investigated in real plant condition. To include all the aspects of process, a mathematical model with reasonable assumptions was developed and then validated against the real plant data. Based on the obtained results, increasing propane concentration leads to increase in propylene yield and decrease in ethylene yield. Besides, run length of process was obtained to be longer in the cases with higher propane content in the feed stream.

Proposing novel strategies for minimization of gas flaring is currently of a great importance. Such strategies could eliminate the drawbacks of burning purge gas and even lead to higher process efficiency. Accordingly, a recovery unit based on membrane separation is proposed in the present contribution. This separation unit is aimed to remove hydrogen, carbon oxides, and methane from the purge gas. Furthermore, the recovered streams are sent to the upstream units as supplementary feeds. In this regard, the stream containing methane is sent to the steam reformer, while the hydrogen and carbon dioxide rich stream is injected into the methanol synthesis reactor. Different strategies are suggested and the best one is selected in terms of enhanced production capacities of synthesis gas and methanol. In order to implement the evaluations, a mathematical model composed of mass and heat balances is applied. Furthermore, the response surface methodology is employed to determine the optimum operating conditions. Consequently, more than 300 tons/year emission of carbon dioxide is inhibited by applying the proposed configuration. Besides, more than 4.6% increase in the methanol production capacity and about 1% decrease in the stoichiometry number of product are the advancements of system working under optimum conditions.

The applicability of zeolites in controlling the emission of greenhouse gases (GHGs) like carbon dioxide, the most significant GHG, is investigated herein. The structure and properties of conventional and nanosized zeolites are initially introduced; subsequently, the adsorption capacities and selectivities of various types of zeolites are reviewed. Thereafter, the effects of determining factors such as the silica-to-alumina ratio, type of cation, temperature, and pressure are discussed. The zeolites that are beneficial for the storage and/or separation of carbon dioxide are introduced and compared. The analysis results reveal that types X, Y, and A zeolites are beneficial for both the storage and separation of carbon dioxide. Chabazite, which is a natural zeolite, exhibits high potential for the separation of carbon dioxide from methane-rich gaseous streams, such as natural gas and landfill gas. Type ZK-5 is also highly successful in the separation of carbon dioxide from nitrogen-rich streams, such as flue gas. Further investigation of nanosized zeolites revealed that both adsorption capacity and selectivity could be enhanced by reducing the size of zeolites through the synthesis method and further modification via amines impregnation and ion exchange.

The necessities of hydrogen and olefins productions are motivations for exploring new and multipurpose processes. Moreover, a suitable strategy to control the emission of carbon dioxide is its utilization in the conversion of chemicals. Carbon-dioxide-assisted conversion of ethane to hydrogen and ethylene is a non-cracking route aimed to reduce energy consumption and carbon dioxide emission, as well as to produce hydrogen, in future petrochemical plants. Accordingly, carbon-dioxide-assisted conversion of ethane to ethylene and hydrogen over alumina-supported cobalt-molybdenum catalysts are examined in the present study. This method would decrease the undesired impacts of carbon dioxide release on the environment and also enhance the efficiency of ethane conversion to ethylene in terms of lower energy consumption and hydrogen production. The catalyst samples are characterized by X-ray diffraction, H2-TPR, and nitrogen adsorption/desorption methods. Moreover, sensitivity analysis experiments are conducted to determine the effects of temperature (600−700 °C) and reactant to catalyst ratio (2250−9000 Lreactant/kgcatalyst.hr) on the conversions of reactants as well as product yields. The highest initial conversions (88 % for ethane and 28 % for carbon dioxide) are observed at 700 °C and GHSV = 2250 Lreactant/kgcatalyst.hr over a catalyst sample including 3.4 wt. % cobalt and 13.6 wt. % molybdenum. The highest initial hydrogen yield (59 %) was also obtained in the same condition. The highest initial ethylene production (43 %) is observed in the case of 4.4 wt.% cobalt and 7.5 wt.% molybdenum at 700 °C and GHSV = 9000 Lreactant/kgcatalyst.hr. The effect of time on stream is also determined to investigate the stability of catalyst samples. Slight changes in the conversions and product yields are observed indicating the stable performance of the catalysts in the studied reaction condition.

Developing integrated processes to transform lignin-derived compounds into value-added products is a promising means for diminishing the aftereffects of conventional routes. Carbon nanotube supported catalysts are currently major trends. In this regard, the transformation of anisole and cyclohexanone by Carbon-nanotube-supported nickel catalysts in the presence of hydrogen and simulated lignin-derived synthesis gas is investigated. The effect of catalyst functionalization is also evaluated. Acid, thermal, and plasma methods are employed to functionalize the catalysts. The samples are evaluated at 400 °C and 20 bar. 83.7–86.4% and 70.1–75.4% of anisole conversions in hydrogen- and syngas-assisted reactions were managed, respectively. The highest conversions in the presence of hydrogen and syngas were obtained over the acid- and thermally-treated samples, respectively. Cyclohexanone, phenol, benzene, toluene, cresols, cyclohexene, and trimethylcyclohexane were the major products of anisole conversion. 88.5–90.8% and 79.7–87.7% of cyclohexanone conversions were managed by hydrogen- and syngas-assisted processes, respectively. Acid- and plasma-treated samples offered the highest conversions in the hydrogen- and syngas-assisted reactions, respectively. The major products of cyclohexanone conversion included cyclohexene, cyclohexanol, cresols, benzene, and phenol. The results of the present study demonstrated that an integrated lignin-based process can be managed for the production of chemicals from lignin-derived syngas, catalyst, and bio-oil.

Owing to concerns associated with energy consumption and energy intensive methods in the chemical industries, the present study aims to investigate production of some downstream products of natural gas in a recuperative configuration. Accordingly, simultaneous production of dimethyl ether from methanol and syngas and also methyl formate from methanol is investigated in a catalytic heat-exchanger reactor assisted with water perm-selective membranes. Dimethyl ether synthesis from methanol and syngas are exothermic reactions supplying required energy for the methanol dehydrogenation reaction. Produced waters in both exothermic sides are eliminated from reaction media by permeation through the perm-selective membranes equipped on the inner and outer surfaces of the reactor. A feasibility study is implemented through a mathematical model based on mass and energy balance. Genetic algorithm as a powerful method in nonlinear optimization problems is applied to obtain optimum operating conditions. 97% methanol conversion to dimethyl ether, 66% methanol conversion to methyl formate and 17% hydrogen conversion are the advancements of the proposed thermally double-coupled double-membrane reactor working under optimum conditions.

Deep eutectic solvents have aroused a great level of interest in recent years. In this regard, a simple model is presented for the calculation of viscosities of a wide range of deep eutectic solvents. Based on a databank covering 156 deep eutectic solvents of different natures, a straightforward, simple, accurate, and global correlation is proposed. This model, which covers wide ranges of temperatures, requires the critical pressure, critical temperature, and one reference viscosity data as its input parameters. Since the model has one set of global constants, it can be used for any DES. Apart from this correlation, a second approach was also taken in this study, which was to obtain the constants of the Vogel-Fulcher-Tamman (VFT) model for all of the investigated DESs. With this approach, the constants are individually fit to each DES, therefore, no physical properties are required as input. The average absolute relative deviation errors of 10.4% and 1.7% for the proposed model and the VFT model, respectively, are compared to literature models. The results indicate that the proposed correlation, in addition to its acceptable accuracy and simplicity, is a general model for the estimation of the viscosities of different-natured deep eutectic solvents.

Thermal conductivity data are reported for nanofluids consisting of 1–4 volume % bentonite particles dispersed in n-pentadecane, potentially for oil-based drilling fluids. The measurements were conducted at temperatures between 298 K and 393 K. The thermal conductivity increases with increasing nano particle concentration, attaining a maximum enhancement of 16.6% in nanofluids containing 4 volume % bentonite. The temperature behavior of the thermal conductivity in nanofluid follows closely that of the base fluid, i.e. n-pentadecane. The effect of temperature on the viscosity of nanofluids was also investigated. The viscosity decreases with increasing temperature at a constant nano particle volume fraction. As expected, the viscosity also increases with increasing nano particle concentration. Cloud point temperatures of nanofluids were measured as a function of particle volume fraction. Cloud point temperatures increases with increasing particle concentration, attaining a maximum increase of 3.10% in nanofluids containing 4 volume % bentonite. Correlations for the thermal conductivity and viscosity are presented for bentonite/n-pentadecane nanofluids with acceptable accuracy.

Following importance of investigating new sources of energy with highly efficient processes, a new configuration for simultaneous production of high purity dimethyl ether (DME), hydrogen and methyl formate (MF) is numerically studied in this work. In this regard, a catalytic heat-exchanger reactor assisted with two different membranes for methanol conversion and in-situ separation of products is simulated. The interesting feature of this system is utilizing only one feedstock (i.e. methanol) to produce different valuable products. Methanol is dehydrated through an exothermic reaction and supplies required energy for the methanol dehydrogenation reaction. Produced water in the exothermic side and produced hydrogen in the endothermic side are separated by permeation to particular membranes. A steady state one-dimensional plug flow model is developed to evaluate molar and thermal behavior of the system. Optimum operating conditions are determined applying genetic algorithm as a powerful optimization method. The proposed configuration working under optimum conditions promotes methanol conversion to DME to % 95.1 and methanol conversion to MF to % 99.6 providing high purity products in the output streams.

The present study aims to presents two new configurations to improve dimethyl ether (DME) production rate besides producing methyl formate (MF) and hydrogen. In this regard, a thermally coupled reactor (TCR) and an integrated thermally coupled membrane reactor (TCMR) with feature of simultaneous production of DME, MF and hydrogen from methanol is proposed. A palladium–silver membrane with high hydrogen permeation rate is utilized to boost hydrogen recovery and MF production rate in TCMR. A one-dimensional plug flow model is considered to evaluate molar and thermal performance of the proposed configurations. Effect of various operating conditions such as inlet flow rates and permeation side configurations on the temperature profiles, methanol conversion, and DME and hydrogen production rate is studied numerically. Utilizing TCR and TCMR configurations promotes methanol conversion to DME to %85 and %87, respectively. Besides, a %22 increase in methanol conversion in the endothermic side was observed applying the hydrogen perm-selective membrane. Generally, higher methanol conversion in both endothermic and exothermic sides and hydrogen production rate in the permeation side was observed using a sweep gas with higher flow rates and lower temperature.

Due to a plenty of advantages, dimethyl ether (DME) is currently receiving a great deal of attention. Efficient ignition, non-toxic emissions, high heating value, easy and safe transportation, and the capability of converting to a variety of products are the major advantages of DME. Despite diverse technologies for DME manufacturing, methanol dehydration is currently the most well-developed route. Therefore, different aspects of this route are currently being investigated. Chemistry of methanol dehydration on the surface of solid-acid catalysts, kinetic modeling for the derivation of rate expressions, conventional reactors, and innovative configurations are reviewed in detail in their present contribution. The most significant factors affecting the rate of methanol conversion are investigated. By focusing on the research, the advancements of new systems are introduced as well. By evaluating the drawbacks of current technologies and the shortcomings of the available research, a prospect for the future is set.

Adsorption isotherms of pure methane and nitrogen and their binary mixtures on Zeochem Co. zeolite 5A were measured using a static volumetric apparatus. Pure isotherms were measured at (273, 283, 303, 323, and 343) K and pressures up to 10 bar, while binary data were measured at (303 and 323) K and different pressures and bulk gas phase compositions. Experimentally measured data were validated using the integral thermodynamic consistency test. In contrast to the aforementioned binary measurements, predictions of different thermodynamic models utilizing pure adsorption isotherms were used to describe binary adsorption behavior of methane and nitrogen over zeolite 5A. Models based on the thermodynamic theory of solutions such as ideal adsorbed solution theory, vacancy solution models, and two-dimensional equations of state were used for this purpose. Experimental and predicted equilibrium data were compared through the appropriate phase diagrams. Predicted selectivity curves were compared against experiment...

Deep eutectic solvents (DESs) mostly comply with the principles of green chemistry. Therefore, they are being widely investigated due to their great potential for a variety of applications in the industries. However, it is necessary to have accurate (thermo)-physical property information on any solvent before it can pave its way into the industries. Among such properties, density as a function of temperature is one of the most important. In this study, a simple, accurate and global correlation is proposed to estimate the densities of a large number of DESs of different natures. The proposed model is a function of the critical temperature, critical volume and acentric factor of the DES, as well as the temperature of the system. In this way, the model is capable of accurately predicting the densities of DESs without the need for any reference temperature density data, in contrast to most of the literature models that do require a reference data point. The average relative error for 149 DESs of different natures was estimated to be 3.12% by the proposed model, indicating its accuracy compared to previous models.

Following the importance of equilibrium data of biomass components as well as octane boosters, the isothermal vapor-liquid behaviors of binary and ternary systems including hexane, toluene, and anisole, and ternary system of methyl tert-butyl ether, hexane, and toluene were investigated at 313.2 K. To do so, the Othmer still was employed to collect the experimental data. Furthermore, thermodynamic calculations were implemented by the Peng-Robinson equation of state and UNIQUAC and NRTL activity coefficient models. The whole binary systems passed the isothermal thermodynamic consistency test of Herington. Based on the obtained results, no azeotrope was observed. Moreover, the obtained errors of calculation imply that UNIQUAC equation is suitable for the representation of the vapor and liquid phases compositions.

The development of theoretical models for the estimation of physical properties of nanofluids such as viscosity is currently of a great deal of attention. In this regard, the present contribution aims to develop the friction theory for the correlation of nanofluid viscosity data. To do so, the Peng-Robinson and Esmaeilzadeh-Roshanfekr equations of state are applied to incorporate the repulsion and attraction pressure terms in the residual viscosity term of the friction model. 711 experimental data points of various nanofluids including water, methanol, and ethylene glycol as base fluids and Al2O3, SiO2, TiO2, and ZnO as nanoparticles were collected. The average absolute relative deviations of the collected data for 18 nanofluids are 2.38 and 2.46% for the Peng-Robinson and Esmaeilzadeh-Roshanfekr equations of state, respectively, and the R-squared values are 0.9978 and 0.9979 for the Peng-Robinson and Esmaeilzadeh-Roshanfekr equations of state, respectively, indicating very good performance of the developed model. The highest average absolute relative deviations were found to be 8.09% and 6.18% for water+TiO2 and water+ZnO nanofluids, respectively. However, the average error of viscosity calculations for almost all the cases is 16%.

Following energy concerns, global warming issues, and urgency of exploring new sustainable and renewable sources of energy, exploring new routes for the production of energy carriers and valuable chemicals is currently of a great interest. In this regard, the production of olefins and gasoline (aromatics) from biomass feedstocks is state of the art. Accordingly, probable routes for converting biomass/bio-oil feedstocks to olefins and gasoline (aromatics) were investigated in this study (Pyrolysis or liquefaction for the production of bio-oil followed by hydrodeoxygenation or catalytic cracking for bio-oil upgrading to olefins and gasoline-type fuel is the most effective route. Effects of various parameters on the production of bio-olefins and biogasoline were studied. Feedstock type, catalyst, temperature, and catalyst-to-feed ratio are the most effective parameters on the yield of the product. In order to explore the optimum conditions for higher yields of products and lower yield of coke, previous studies were summarized in this study.