Unreacted Methanol Research Articles

Thermodynamic and economic analysis of a novel thermoelectric-hydrogen co-generation system combining compressed air energy storage and chemical energy

With the adjustment of energy structure, the proportion of renewable energy is gradually increasing, and how to solve the problem of renewable energy consumption is becoming more and more prominent. Therefore, a novel thermoelectric-hydrogen co-generation system combining compressed air energy storage (CAES) and chemical energy (CE) is proposed. For energy storage, the system uses adiabatic compression with liquid piston to reduce the generation of compression heat, while using the generated compression heat to preheat the methanol. For energy release, the methanol is fed into the methanol steam reforming reactor (MSR) and the methanol decomposition reactor (MDR) in certain proportions for the hydrogen production reaction; the unreacted methanol and the carbon monoxide produced by the MDR are used as make-up heat for the reactors and the high-pressure air before the turbine, while the exhaust waste heat supplies heat to the customer. The thermodynamic, economic and environmental performances of the system were investigated separately by developing a mathematical model describing the system. The results show that under the design conditions, the system has an energy storage density of 12.00 kWh/m3, an energy efficiency of 88.47 %, an exergy efficiency of 77.04 %, a lifetime net present value of 59.20 M$, a payback period of 4 years, and a CO2 emission per unit of energy output of 227.85 kg/MWh. Increasing the thermostatic heat source temperature and increasing the reactor diameter and length increased the methanol conversion rate. Increasing heat exchange effectiveness of the heat exchanger and heat source temperature can all improve system thermodynamic and economic performance. The energy storage density, energy efficiency, net present value and profitability of the system varied parabolically with the reactor tube diameter. The system energy storage density had a maximum value of 12.03 kWh/m3 at a reactor diameter of 0.040 m.

Multi-objective optimization of a compression ignition engine using on-board methanol reforming

The dual-fuel combustion technology utilizing hydrogen and diesel fuel shows potential in enhancing the performance of compression ignition engines and reducing carbon emissions. However, this approach is accompanied by several significant challenges, such as hydrogen transportation and storage, as well as low combustion efficiency at low loads. To address these challenges, this study integrates low-temperature combustion technology with online hydrogen production through methanol steam reforming to achieve efficient and clean combustion. The results of methanol steam reforming, mainly consisting of hydrogen, carbon dioxide, and unreacted methanol, is premixed via port injection as a low-reactivity fuel. Simultaneously, diesel fuel is directly injected into the cylinder as a high-reactivity fuel to achieve reactivity-controlled compression ignition mode. The primary fuels employed in compression ignition engines comprise reformate gas (mainly hydrogen), unreacted methanol, and diesel. This combination is collectively termed as tri-fuel combustion. This study utilizes a combination of genetic algorithms and 3D engine simulation to determine the optimal strategy for the methanol/reformed gas/diesel tri-fuel engine under different loads. The results of the optimization reveal that the tri-fuel combustion mode has the highest indicated thermal efficiency, surpassing the methanol/diesel dual-fuel mode and the reformed gas/diesel dual-fuel mode. Meanwhile, the optimized engine demonstrates significantly lower NOx and soot emissions than those required by the Euro VI emission regulations. Additionally, the study summarizes engine operating parameters impact on performance. Moreover, the tri-fuel combustion mode has a distinct advantage in increasing the methanol energy substitution rate at all three different loads. The dual-fuel mode leads to increased unburned hydrogen and methanol concentration near cylinder liner due to lower combustion temperature. In contrast, tri-fuel mode substantially reduces unburned hydrogen and methanol due to high combustion temperature and methanol reactivity.

Failure analysis on abnormal damage and corrosion of methanol distillation column in MTBE production plant

Methyl tert-butyl ether (MTBE) is a commonly used gasoline additive that improves combustion and reduces pollutant emissions. The methanol distillation column is an integral part of the recovery system in MTBE production plants, used to separate and recycle unreacted methanol from water through distillation. During regular maintenance, severe damage to the support ring and abnormal perforations in the column were discovered. Despite repair welding, the column still leaked. Various investigations were conducted to determine the root cause of the failure. The chemical composition, metallurgical structure, and hardness of the support ring and column materials were examined, and the medium in the column was characterized. The medium at the bottom of the column was unexpectedly subjected to an undesirable excessive acidity (with a pH of approximately 3.8) dominated by the upstream etherification reaction deacidification, and provided common basic conditions for localized pitting and uniform corrosion of low carbon steel. What's more, the appearance of clean and smooth corrosion pits and scour traces on the perforated column wall, as well as honeycomb pits and arc-shaped layered traces on the support ring, revealed that the corrosion failure was intensified due to the interaction of selective erosive corrosion and medium concentration accelerated corrosion caused by multiple corrosion types of the acidic medium. In addition, the unpolished surface from incomplete repair welding was another significant factor. Based on these findings, specific countermeasures were implemented and proved effective.

Analysis of methanol recovery using component specific reaction kinetics in biodiesel synthesis

ABSTRACT Transesterification is the process of transmutation of fatty acids to alkyl esters (biodiesel) when reacted with alcohols such as methanol, ethanol, etc. The unreacted methanol in the process downstream can be recovered and reused economically by integrating methanol recovery with transesterification, thereby mitigating the environmental and health hazards caused by direct release of the same. The present work deals with the simulation of methanol recovery integrated transesterification of poppy seed oil in ASPEN Plus process simulator. The transesterification process is simulated using a component-specific kinetic model by considering four constituent triglycerides of poppy seed oil, namely, oleic acid, palmitic acid, linoleic acid, and stearic acid. The model is made more comprehensive by incorporating six-step reaction mechanism for each triglyceride to simulate its respective alkyl ester conversion. Recovery of excess methanol is implemented using a distillation-based methanol recovery unit. The prediction accuracy of the model is found to be 3.51% when the model predicted biodiesel yield is compared with the corresponding experimental values. The validated model is used to analyze the effect of methanol-to-oil ratio, reboiler duty, temperature, pressure and reflux ratio on methanol recovery. From the analysis, it is found that a methanol-to-oil ratio of 6:1 and process temperature of 60°C corresponds to maximum biodiesel yield. For the maximum yield condition, a maximum methanol recovery of 0.945 can be attained economically at a reboiler duty of 500 cal/s and reflux ratio 2.

Effect of blending ratio of biofuel from used cooking oil with Dexlite

Indonesia is committed to accelerating the clean energy transition through the biodiesel policy to achieve net zero emission. The commitment to use palm oil as a biofuel base material will support Indonesia in achieving its energy security and energy mix target of 23% in 2025. This article discussed the characteristics of the blended fuel between biofuel from used cooking oil and Dexlite from PERTAMINA products. The blending process is carried out with the biofuel: Dexlite ratio as follows: 5:95, 10:90, 15:85 20:80, 25:75 and 30:70. The results revealed that the best experiments for acid number were obtained at the B5 blending ratio of 0.039 mgKOH/(g sample), saponification number at the B5 blending ratio of 1.066 mgKOH/(g sample), flash point at the B20 blending ratio at a temperature of 101°C, 90% distillation at the B10 blending ratio at a temperature of 213°C, and the density at the blending ratio B15 is 837 kg/m3. From these results, only the density parameter does not meet the biodiesel quality standards based on SNI 7182:2015. These results indicate that the addition of 30% biofuel to Dexlite can still be used as a fuel for diesel vehicles by applying a better washing method for KOH catalyst residue and unreacted methanol residue.

Experimental Studies of Graphene-Coated Polymer Electrolyte Membranes for Direct Methanol Fuel Cells

Abstract The two main technical limitations of direct methanol fuel cells (DMFCs) are the slow kinetic reactions of the methanol oxidation reaction (MOR) in the anode and the crossing over of unreacted methanol through the proton exchange membrane (PEM). It is a common practice to use Nafion membranes as PEMs, which have high ion exchange capacity. However, Nafion-based membranes also have high fuel permeability, decreasing fuel utilization, and reducing the potential power density. This article focuses on using graphene-coated (Gr-coated) PEMs to reduce fuel crossover. Protons can permeate across graphene, and thus, it can be employed in various devices as a proton conductive membrane. Here, we report the efficiency of Gr-coated Nafions. We tested performance and crossover at three different temperatures with four different fuel concentrations and compared it to a Nafion PEM that underwent the same test conditions. We found that the adhesion of Gr on to PEMs is insufficient for prolonging fuel cell operation, resulting in Gr delamination at high temperatures and higher fuel crossover values compared to lower temperature testing. The results for 7.5M methanol fuel show a reduction of up to 25% in methanol crossover, translating to a peak power density that increases from 3.9 to 9.5 mW/cm2 when using a Gr-coated PEM compared to a Nafion PEM at 30 °C.

Selective conversion of methanol to aromatics with superior catalytic stability by relay catalysis over quadruple ZSM-5 sequence beds with gradient-increasing acidity

Methanol to aromatics (MTA) process is an attractive non-petroleum route for producing high-valued aromatics, but simultaneously achieving high catalytic stability and high aromatics selectivity remains a challenging research target. Herein, we present a highly efficient MTA process by quadruple tandem relay catalysis containing four layers of nanosized ZSM-5 with different acidity features in series. Specifically, four ZSM-5 catalysts with gradient-increasing acid density were sequentially packed in the tubular fixed bed reactor for reaction. Among them, ZSM-5 with a high SiO2/Al2O3 ratio as 480 was packed in top layer to convert methanol into light alkanes and alkenes intermediates, then these reaction intermediates and a small amount of unreacted methanol were transported on other two ZSM-5 layers with lower SiO2/Al2O3 ratio as 240 and 120 respectively for stepwise converting to aromatics. In particular, Zn doped ZSM-5 with a low SiO2/Al2O3 ratio of 60 was packed in the bottommost layer which further promoted aromatization of upstream light hydrocarbons. Accordingly, aromatics selectivity was significantly increased to 32.6% using the sequence beds, much higher than 17.6% for the widely recognized two-step MTA. Based on deliberate analysis of methanol conversion and coke formation behavior in different beds, we demonstrate that a methanol concentration gradient existed along the sequence beds which remarkably decreased alkylation of aromatics induced by methanol. So, the catalyst stability of the ZSM-5 located in the bottommost layer was significantly enhanced to 238 h, which was 3-folds compared with the traditional two-step methanol conversion. The present work offers a promising strategy for MTA via tandem ZSM-5 catalysis systems, which has an active impact on the solving of the energy and environmental problems existing in the production process of aromatics.

Managing Fuel Crossover in Direct Methanol Fuel Cells By Optimizing the Anode Microporous Layer

Direct methanol fuel cells (DMFCs) have been considered a promising candidate as a replacement for small scale and portable power applications, however, there are technical barriers that have prevented widespread use of DMFCs in commercial applications. Of these technical barriers, unreacted methanol crossing over from the anode to the cathode has been identified as a primary limiting factor of DMFCs as this phenomenon results in lowered efficiency and reduced open circuit voltages (OCVs) on the cathode, and ultimately limits the OCV of the cell itself.1 In this work, the authors used an anode design proposal provided by (Metzger et al, 2021, JEECS-20-1185) to create a strongly hydrophilic microporous layer (MPL) on the anode gas diffusion layer (GDL) to reduce methanol crossover by increasing the capillary pressure in the pores of the MPL required for the methanol to crossover prior to reacting.2 The authors fabricated three membrane electrode assemblies. (MEAs) MEA 1 was fabricated using a traditional hydrophobic MPL on the anode GDL, whereas MEAs 2 and 3 were fabricated using customized hydrophilic MPLs. The GDL for MEA 2 was heat treated at 165 F for one hour and the GDL for MEA 3 was dried in atmospheric conditions for 24 hours. A peak power density of 71 mW/cm2 was observed using 1M methanol solution with MEA 1. Using this approach, the authors were able to achieve a peak power density of 68.1 mW/cm2 and 70.1 mW/cm2 with MEAs 2 and 3, respectively, using 3M methanol solution. Additionally, the authors achieved a peak power density of 32 mW/cm2 and 30.7 mW/cm2 using 7.5M methanol solution. This study provides a framework for creating low-cost hydrophilic MPLs that can be utilized on the anode GDL to reduce fuel crossover in DMFCs. Figure 1

DRIFTS investigation of methanol oxidation on CeO2 nanoparticles

The mechanism of the oxidation of methanol on the surface of heat treated CeO2 nanoparticles was studied using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The study was carried out under high vacuum to ensure no interference from unreacted physisorbed methanol and compared to a similar analysis under pseudo-flow conditions. When methanol reacts with the CeO2 surface, it either chemisorbs to a single cerium atom creating monobound (m) methoxy or to two neighboring cerium atoms forming bridged (b) methoxy groups. From the evacuated analysis, formate production depends directly on the presence and transformation of b-methoxy groups. Hydroxyls are found to facilitate the formation of the two surface methoxy groups, react with m-methoxy groups creating additional b-methoxy groups, and enable the transformation of b-methoxy groups to bidentate formate groups. The reaction mechanism is elucidated through the use of temperature dependent peak height analysis of the collected DRIFTS spectra which are correlated to the transforming surface bound species.

Separation of Anisole and Valuable Byproducts from Liquid Reaction Mixtures by Solvent Extraction and Multicomponent Distillation

Anisole (methoxybenzene) is a widely used organic intermediate that can be synthesized via vapor-phase alkylation of phenol by methanol in the presence of a commercial NaX zeolite as a catalyst (SiO2:Al2O3 ratio of 2.6:3). The indigenously synthesized anisole is then separated from the multicomponent liquid reaction mixture, consisting of o-cresol, p-cresol and p-xylen, along with unreacted methanol and phenol. The separated anisole has substantial demand for applications in the chemical, pharmaceutical, plastics and pesticides industries. Separation of individual components from the reaction mixture requires identification of techniques that could be scaled up. Distillation is one of the most dependable techniques for the separation of multicomponent liquid mixtures. The novelty of the present study is the synthesis and separation of anisole along with individual components of methanol, phenol and o-cresol from its reaction mixture using a single distillation column under atmospheric and vacuum conditions, respectively. Through this process, the purity of the resulting methanol, anisole and phenol were found to be 99.99, 99.80 and 98.29% by simple distillation, whereas 91.0% pure o-cresol was separated by vacuum distillation due to its high boiling point. The experimental results were used to calculate the material, individual component and energy balances, whereas the PRO/II™ process simulation was performed to scale-up the process. On the other hand, anisole recovery from a synthetic multicomponent liquid mixture was also successfully conducted using solvent extraction. The overall observations found the integration of solvent extraction with distillation to be an effective, economical and dependable solution for the isolation of anisole and other important by-products.

The detection of the precursors of the photorearranged products of 3-hydroxyflavones in selected solvents from UV-visible spectra in situ.

Mechanistic studies relating to the photochemistry of 3-hydroxy-2-phenyl-4H-chromen-4-one (3HF) and 6-chloro-3-hydroxy-2-phenyl-4H-chromen-4-one (Cl-3HF) have been reinvestigated in selected solvents. The UV-visible spectra of the photoproduct(s) of 3HF and Cl-3HF have been computed in situ via subtracting the spectra of unreacted substrates, with acetonitrile (ACN) and methanol (MeOH) as solvents. These spectra turn out to be different from the spectra of the corresponding isolated photoproducts: 3-hydroxy-3-phenyl-indan-1,2-dione and 6-chloro-3-hydroxy-3-phenyl-indan-1,2-dione (referred to as dione ). Analyses of the photoproduct(s) via GC-MS show the formation of a single detectable product, i.e., the corresponding dione. On the basis of some experimental observations, it is proposed that the primary photoproduct in situ is 2,3-epoxy-2-hydroxy-1-indanone (referred to as epoxide) instead of dione as reported in previous years. Earlier, epoxide has been proposed to be the intermediate in the mechanism for the formation of dione. This is the first report where the formation of epoxide has been directly detected in the selected solvents. On the other hand, both dione and epoxide (2 : 1) are shown to be formed with MeOH as solvent. The second important finding is that epoxide and dione interconvert in the dark, depending upon the environment. With ACN as solvent, pure dione in the dark is kinetically and partially converted to epoxide. With MeOH as solvent, epoxide is instantly and partially converted to dione until both are in equilibrium. However, a solution of dione in MeOH remains stable in the dark. The photoformation of epoxide is quantitative with ACN as solvent and it is sufficiently stable. It has been further observed that epoxide solutions of 3HF and Cl-3HF in ACN are quantitatively converted into 3-phenylisobenzofuran-1(3H)-one and 6-chloro-3-phenylisobenzofuran-1(3H)-one, i.e., the corresponding phthalides, through the loss of CO when kept in the dark for some days. A mechanism has been proposed where epoxide has been shown to give dione and/or phthalide via selective C-O or C-C bond cleavage in the oxiranyl ring, respectively. The selection of this cleavage depends mainly on the solvent system and the substituents in the parent flavones.

Thermodynamic and economic assessment of a PEMFC-based micro-CCHP system integrated with geothermal-assisted methanol reforming

A micro-combined cooling heating and power (CCHP) system integrated with geothermal-assisted methanol reforming and incorporating a proton exchange membrane fuel cell (PEMFC) stack is presented. The novel CCHP system consists of a geothermal-based methanol steam reforming subsystem, PEMFC, micro gas turbine and lithium bromide (LiBr) absorption chiller. Geothermal energy is used as a heat source to drive methanol steam reforming to produce hydrogen. The unreacted methanol and hydrogen are efficiently utilized via the gas turbine and PEMFC to generate electricity, respectively. For thermodynamic and economic analysis, the effects of the thermodynamic parameters (geothermal temperature and molar ratio of water to methanol) and economic factors (such as methanol price, hydrogen price and service life) on the proposed system performance are investigated. The results indicate that the ExUF (exergy utilization factor the exergy utilization factor), TPES (trigeneration primary energy saving) and energy efficiency of the novel system can be reached at 8.8%, 47.24% and 66.3%, respectively; the levelized cost of energy is 0.0422 $/kWh, and the annual total cost saving ratio can be reached at 20.9%, compared with the conventional system. The novel system achieves thermodynamic and economic potential, and provides an alternative and promising way for efficiently utilizing abundant geothermal energy and methanol resources.

PENGARUH KECEPATAN PENGADUKAN DAN SUHU REAKSI PADA ESTERIFIKASI MINYAK MENTAH DEDAK PADI BERKANDUNGAN ASAM LEMAK TINGGI

Rice bran oil (RBO) derived from rice bran (RB) which could use as an alternative raw material for biodiesel production. Rice bran (dedak) are used as feed for poultry, pigs, and some dairy cattle because they are relatively cheap and do not require processing. The utilization of these oil further cheapen the cost of biodiesel and increased the economonic value of RB. The choice of RBO as a raw material for biodiesel due to the rice bran oil’s potentials. RBO is considered to be one of the most nutritious oils due to its favorable fatty acids composition and a unique combination of naturally occurring biologically active and antioxidant compounds (oryzanol, tocopherol, tocotrienol, phytosterol, polyphenol, dan squalene). The research emphazised on esterification reaction because of the rapid increase of FFA content in RBO after the milling of rice. Storage time of RB increased the FFA content. Mixing velocity dan time reaction was the other two variables which are affecting the esterification reaction. Those two variables are studied in this experiment.
 Experiment were designed to examine the mixing velocity and temperature reaction to the conversion of fatty acid methyl ester (FAME). Reaction condition 20:1 molar ratio methanol to FFA content and 5%-v/v catalyst (to the oil) was used in all experiments. Mixing velocity and time reaction was arranged as follows: 500, 750, 1000 rpm and 40, 50, 60oC, respectively. Research conducted in four parts: soxhlet extraction with n-hexane as a solvent; oil-solvent separation process; and the last step was esterification reaction. Reaction conducted on three neck round bottom flask equipped with magnetic stirrer, refluk condenser and thermometer. Crude product was separated first from unreacted methanol, glycerol, and catalyst prior to physical analyzed of biodiesel’s properties. Conversion of FAME was calculated from acid value difference, after and before reaction conducted.
 It was found that mixing velocity influenced the FAME conversion not significantly (specially in crude rice bran oil high fatty acid content esterification); increasing in temperature will increase the FAME conversion; kinetic reaction controlled by chemical reaction; and biodiesel product from this research already fullfill the requirements of Indonesian Standard of Biodiesel (FBI-SO1-03).

Design and simulation of high purity biodiesel reactive distillation process

Abstract Biodiesel is a promising energy substitute of fossil fuels since it is produced from renewable and biodegradable sources. In the present work, reactive distillation (RD) process is designed and simulated using Aspen Plus process simulator to produce biodiesel of high purity through esterification reaction. The simultaneous reaction and separation in same unit enhances the biodiesel yield and composition in RD process. Two flowsheets are proposed in present work. In the first flowsheet, the unreacted methanol is recycled back to reactive distillation column. Biodiesel with 99.5 mol% purity is obtained in product stream while the byproduct stream comprises 95.2 mol% water, which has to be treated further. In the second flowsheet, a part of methanol recycle is split and purged. In this case, the biodiesel composition in product stream is 99.7 mol% whereas water composition is 99.9 mol% in byproduct stream, which can be reused for other process without treatment.

Hydrophobic nano-bamboo fiber-reinforced acrylonitrile butadiene styrene electrospun membrane for the filtration of crude biodiesel

Due to the high solubility rate of glycerol in water, gallons of water are used for the purification of raw biodiesel. Hence, washing of biodiesel is a major challenge for its large-scale production. The present work reports the fabrication of a novel superoleophilic and hydrophobic nanofibrous membrane based on bamboo fiber and acrylonitrile butadiene styrene (ABS), by electrospinning for the purification of biodiesel. The morphology of the membrane was characterized by scanning electron microscope (SEM) and atomic force microscope (AFM). The addition of bamboo fiber increases the surface roughness of the electrospun fiber, thus modifying the surface wetting behavior. The wettability of the membrane was measured by goniometer and the water contact angle was found to be increased from 119° to 143° with the addition of 2 wt.% of the bamboo fiber in pure ABS solution. The superior hydrophobic and superoleophilic properties enable the membrane to separate the free glycerol and unreacted methanol from crude biodiesel. The purity level of the filtered biodiesel was checked using the light scattering method and found to meet the ASTM standard. The gravity-driven setup with bamboo fiber reinforced ABS membrane is a cost-effective method, eliminating water washing procedure for the biodiesel purification.

An experimental-based energy integrated process for biodiesel production from waste cooking oil using supercritical methanol

Biodiesel has been recognised as one of the effective, green, renewable and sustainable fuels. It is derived from renewable living resources either animal fats or vegetable oils. Biodiesel production in the absence of catalyst using supercritical methanol has recently been receiving significant attention. Non-catalytic transesterification reaction eliminates the difficulties of catalyst preparation and separation processes. Although it has shown high conversion for the reactants with relatively short reaction time in comparison with the conventional catalytic transesterification processes, it has some disadvantages including higher reaction temperature and pressure, large excess of methanol to oil (M:O) molar ratio and higher energy consumption. In an attempt to mitigate these problems, an experimental study followed by process design/integration for biodiesel production from waste cooking oil (WCO) has been performed. A low-quality WCO collected from local restaurants has been selected as a feedstock for the reaction. The experimental phase of the transesterification reaction together with an optimisation procedure resulted in the optimised conditions of M:O molar ratio of 37:1, reaction temperature of 253.5 oC, reaction pressure of 198.5 bar in 14.8 min. The maximum yield was 91%. In addition, kinetics of the reaction has been studied concluding an irreversible pseudo first order reaction with a reaction rate constant of 0.0006 s-1. Moreover, thermodynamics of the reaction has been studied at a temperature range of 240 - 270 oC with resulting frequency factor and activation energy of 4.05 s-1 and 50.5 kJ/mol. A kinetic reactor has been simulated using the experimentally determined kinetic and thermodynamic data. The enthalpy content of the reactor product stream has been used to separate most of the unreacted methanol in an adiabatic flash drum. Finally, a scheme has been developed for an energy integrated process in order to maximise the heat recovery. Energy savings resulted from the developed heat exchanger network (HEN) have been concluded as 32.2 % and 23.8 % for both heating and cooling energies respectively, in comparison with an existing process energy requirements in the literature. The amount of heat exchanged for each unit has been determined in addition to composition, temperature and pressure of the streams. Vacuum distillation column has been designed to separate the unreacted triglycerides from biodiesel in order to fulfil the quality restrictions of the final biodiesel product.

Economic analysis of biodiesel production from waste cooking oil

ABSTRACTRenewable diesel fuel or biodiesel is one of the prospective growth inducers that could help to resolve a country’s economic problem and will decrease the nation’s dependence on foreign energy imports. In this context, an economic evaluation of biodiesel production from waste cooking oil is reported in this study. The biodiesel was produced from waste cooking oil by transesterification process. The by-product glycerol produced during transesterification is purified and recovered for its commercial value. Also, unreacted methanol after transesterification is recovered by distillation and recycled for reuse. The biodiesel production facility developed in this study is dedicated to the production of 39,208 metric tons of biodiesel per year. The total capital investment charged to this project is estimated to be Rs. 1,615,133,000. At a value of Rs. 15/kg for feedstock waste cooking oil, a biodiesel cost of Rs. 55/kg was estimated. Along with main revenue from biodiesel, additional revenue of around Rs. 22/kg can be generated from the sale of glycerol. On the whole, the profitability analysis of the study discloses that the modeled biodiesel production plant has the ability to produce biodiesel with unit production cost of Rs. 51/kg and unit production revenue of Rs. 58/kg.

Synthesis promotion and product distribution for HZSM-5 and modified Zn/HZSM-5 catalysts for MTG process

In this study presented here, attempt is made to development of active zeolite base catalyst for gasoline production in methanol to gasoline (MTG) catalytic process based on wet impregnation technique. Synthesis and improvement methods for ZSM-5 zeolite are essential for a wide variety of different reactions in the chemical industry. In this regard, HZSM-5 and promoted Zn/HZSM-5 samples are prepared. HZSM-5 is synthesized by NaOH treatment and then it is promoted using wet impregnation technique. Distribution of hydrocarbons, which produced in catalytic reaction of methanol to gasoline process, are reviewed over synthesized HZSM-5 and promoted samples with Zinc (Zn) element in a fixed-bed continuous flow reactor. The reaction is performed with weight hourly space velocity (WHSV) equal to 4 (gmethanol)·(gcatalysth)−1, at ambient pressure and 370°C. The zeolite samples after preparation are characterized by XRD, SEM, TPD-NH3 and N2 adsorption/desorption isotherms tests. We have finally managed to identify optimized Zn impregnated catalyst (Zn/HZSM-5) that is exhibited good improvements in liquid hydrocarbons production compared to other prepared samples. Optimized sample is prepared with Zn loading equal to 0.75wt.%. For optimized sample, the results showed that in gas phase, produced C5+ component is increased; in addition, produced dimethyl ether and unreacted methanol are decreased compare to other prepared samples. Also in liquid phase, produced xylene and alkyl aromatic components are increased about 9.33%; in addition yield of produced hydrocarbons (produced gasoline) are increased. Also, 30% increase in the weight of oil cut over optimized sample is observed.

One-pot synthesis and recovery of fatty acid methyl esters (FAMEs) from microalgae biomass

We report a scalable method for recovery of cellular lipids and subsequent conversion to products. When in situ transesterification was performed at high solid loadings (>20%(w/w)) by reacting microalgal biomass in acidified methanol (containing 5%(v/v) H2SO4), the released FAMEs were produced at sufficiently high concentrations such that their solubility limit in the reaction medium was exceeded. As a result, the FAMEs spontaneously formed a separate phase lighter than methanol that could be directly recovered without solvent extraction. Further, FAME production rates were easily predicted, even in concentrated biomass slurries, by models derived from fundamental reaction kinetics. Our results also suggest that un-reacted methanol and catalyst, when recovered, could be reused in subsequent reactions. Thus, this “one-pot” process represents a viable method for production of biodiesel from algal biomass since this approach (1) eliminates costs associated with co-solvent (e.g., hexane) use, recovery and storage, (2) is easily scalable by virtue of the reaction not being constrained by mass transport limitations, and (3) facilitates processing of concentrated biomass slurries that would reduce reactor volumes and minimize reactor and handling costs.

Study of an energy-integrated biodiesel production process using supercritical methanol and a low-cost feedstock

The supercritical biodiesel production process has some disadvantages such as: high reaction temperature, large molar methanol-to-oil ratios (R) and large energy consumption. To mitigate these problems, an energy integrated process in which biodiesel is obtained in a continuous tubular reactor operating at a reaction temperature of 280°C, R=20, a residence time of 1h and a pressure of 110bar, is proposed. A low-cost lipid feedstock (chicken oil) was used as raw material for testing the process. The enthalpy content of the stream exiting the supercritical reactor was used to eliminate the unreacted methanol in an adiabatic flash drum. The operating conditions of the adiabatic flash were optimized to meet the specification of water and methanol content in the biodiesel phase and minimize the ester and acid content in the vapor phase. These conditions were: P=0.1bar and T=178°C. For these conditions the methanol content is 88–90% in the vapor phase and lower than 0.2% in the biodiesel phase. A scheme was developed for an energy integrated process maximizing the heat recovery. Composition, temperature and pressure of the streams were determined and also the amount of heat exchanged in each unit. In order to fulfill the quality restrictions the final content of FFA in the biodiesel product had to be further adjusted by adsorption over bleaching silica.