scholarly journals Extractive desulfurization of liquid fuel using diamine-terminated polyethylene glycol as a very low vapour pressure and green molecular solvent

2020 ◽  
Vol 7 (11) ◽  
pp. 200803
Author(s):  
Fatemeh Rafiei Moghadam ◽  
Effat Kianpour ◽  
Saeid Azizian ◽  
Meysam Yarie ◽  
Mohammad Ali Zolfigol

Removal of sulfur compounds from liquid fuel is one of the important issues in the field of energy and environment. Among the available methods, extractive desulfurization (EDS) is of great interest due to its convenient operating conditions. In this study, EDS performance of 4,7,10-trioxatridecane-1,13-diamine (TTD), a very low vapour pressure diamine-terminated oligomeric polyethylene glycol (PEG), was studied. Effect of the influencing factors, as well as multiple extraction, mutual solubility, reusability and regeneration of TTD were investigated. Results showed that the TTD/fuel volume ratio of 0.5 could extract benzothiophene, dibenzothiophene and dimethyl dibenzothiophene with the efficiencies 67%, 74% and 53%, respectively, in less than 1 min at ambient temperature. The distribution coefficient ( K N ) value for removal of dibenzothiophene by TTD was 3.66 higher than that of PEG, and it is similar to K N values (approx. 4) for polyethylene glycol dimethyl ether (as a modified PEG) and Lewis acid-containing ionic liquids. It was observed that spent TTD after five cycles could be regenerated using the back-extraction method. Also, deep EDS was achievable after three times extraction using fresh TTD. Finally, the extraction mechanism was studied using 1 H-NMR. These observations, as well as very low vapour pressure and insignificant dependency of TTD on the initial S-concentration of fuel and temperature, make this extractant to be introduced as a valuable option for green and effective EDS.

1989 ◽  
Vol 54 (4) ◽  
pp. 981-989
Author(s):  
Ján Dojčanský ◽  
Soňa Bafrncová ◽  
Július Surový

On using five hypothetical systems differing in the extent of mutual solubility of components, tie-line slope, and type of binodal curve, the effect is evaluated of systematic errors in the form of absolute deviation in the liquid-liquid equilibrium distribution concentrations on the accuracy of calculated number of theoretical stages of isothermal countercurrent extraction under various operating conditions.


2012 ◽  
Vol 512-515 ◽  
pp. 2200-2206
Author(s):  
Kun Wang ◽  
Jun Guan ◽  
De Min He ◽  
Qiu Min Zhang

Hydrogenation of phenanthrene (PHE HYD) was investigated over a commercial NiW/Al2O3catalyst under practical reaction conditions. GC-MS analysis was utilized to identify the numerous products formed during PHE HYD. The products included dihydrophenanthrene (DHP), 1,2,3,4-tetrahydrophenanthrene (THP), sym-octahydrophenanthrene (1,8-OHP), asym-octahydrophenanthrene (1,10-OHP) and perhydrophenanthrene (PHP), but the cracking products were not found under the reaction conditions. The effects of operating conditions such as temperature, pressure and H2/liquor on PHE HYD were tested in detail. It is found that temperature and pressure had remarkable effect on PHE HYD, but volume ratio of H2/liquor had little effect on PHE HYD at the observation range. The addition of decalin had a positive impact on PHE HYD; it could increase the conversion of PHE and the selectivity to PHP.


2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Swapnil A. Dharaskar ◽  
Kailas L. Wasewar ◽  
Mahesh N. Varma ◽  
Diwakar Z. Shende

A new class of green solvents, known as ionic liquids (ILs), has recently been the subject of intensive research on the extractive desulfurization of liquid fuels because of the limitation of traditional hydrodesulfurization method. In present work, eleven Lewis acid ionic liquids were synthesized and employed as promising extractants for deep desulfurization of the liquid fuel containing dibenzothiophene (DBT) to test the desulfurization efficiency. [Bmim]Cl/FeCl3was the most promising ionic liquid and performed the best among studied ionic liquids under the same operating conditions. It can remove dibenzothiophene from the model liquid fuel in the single-stage extraction process with the maximum desulfurization efficiency of 75.6%. It was also found that [Bmim]Cl/FeCl3may be reused without regeneration with considerable extraction efficiency of 47.3%. Huge saving on energy can be achieved if we make use of this ionic liquids behavior in process design, instead of regenerating ionic liquids after every time of extraction.


Author(s):  
Katharina Warncke ◽  
Amsini Sadiki ◽  
Max Staufer ◽  
Christian Hasse ◽  
Johannes Janicka

Abstract Predicting details of aircraft engine combustion by means of numerical simulations requires reliable information about spray characteristics from liquid fuel injection. However, details of liquid fuel injection are not well documented. Indeed, standard droplet distributions are usually utilized in Euler-Lagrange simulations of combustion. Typically, airblast injectors are employed to atomize the liquid fuel by feeding a thin liquid film in the shear zone between two swirled air flows. Unfortunately, droplet data for the wide range of operating conditions during a flight is not available. Focusing on numerical simulations, Direct Numerical simulations (DNS) of full nozzle designs are nowadays out of scope. Reducing numerical costs, but still considering the full nozzle flow, the embedded DNS methodology (eDNS) has been introduced within a Volume of Fluid framework (Sauer et al., Atomization and Sprays, vol. 26, pp. 187–215, 2016). Thereby, DNS domain is kept as small as possible by reducing it to the primary breakup zone. It is then embedded in a Large Eddy Simulation (LES) of the turbulent nozzle flow. This way, realistic turbulent scales of the nozzle flow are included, when simulating primary breakup. Previous studies of a generic atomizer configuration proved that turbulence in the gaseous flow has significant impact on liquid disintegration and should be included in primary breakup simulations (Warncke et al., ILASS Europe, Paris, 2019). In this contribution, an industrial airblast atomizer is numerically investigated for the first time using the eDNS approach. The complete nozzle geometry is simulated, considering all relevant features of the flow. Three steps are necessary: 1. LES of the gaseous nozzle flow until a statistically stationary flow is reached. 2. Position and refinement of the DNS domain. Due to the annular nozzle design the DNS domain is chosen as a ring. It comprises the atomizing edge, where the liquid is brought between inner and outer air flow, and the downstream primary breakup zone. 3. Start of liquid fuel injection and primary breakup simulation. Since the simulation of the two-phase DNS and the LES of the surrounding nozzle flow are conducted at the same time, turbulent scales of the gas flow are directly transferred to the DNS domain. The applicability of eDNS to full nozzle designs is demonstrated and details of primary breakup at the nozzle outlet are presented. In particular a discussion of the phenomenological breakup process and spray characteristics is provided.


2019 ◽  
Vol 9 (3-4) ◽  
pp. 185-198 ◽  
Author(s):  
Georgina C. Laredo ◽  
Patricia Pérez-Romo ◽  
Pedro M. Vega-Merino ◽  
Elva Arzate-Barbosa ◽  
Alfonso García-López ◽  
...  

Abstract Light cycle oil (LCO) is an inexpensive feedstock for the production of high-added-commercial-value-mono-aromatic compounds such as benzene, toluene and xylenes (BTX). To extend the knowledge on the processing of LCO for BTX production, the hydrocracking reaction was studied using a commercial NiMo/Al2O3 catalyst, ZSM-5 zeolite and their mechanical mixtures (20/80, 30/70 and 50/50) for processing tetralin as model feedstock in a bench-scale-trickle-bed reactor at 450–500 °C, 3.9–5.9 MPa, 1.3 1/h and H2/feed volume ratio of 168–267 m3/m3. Accessible, well-dispersed and strong Brönsted acid sites eased the hydrocracking of tetralin to BTX and the metallic hydrogenation functions from nickel–molybdenum catalysts were also required to minimize deactivation. To achieve suitable tetralin conversions (86–95 wt%), high BTX selectivity in the liquid phase (44–70 wt%) and suitable catalytic activities for coke precursor hydrogenation (to reduce deactivation), NiMo/Al2O3//ZSM-5 mixtures (50–80 ZSM-5) were employed, which probed to be effective.


2016 ◽  
Vol 723 ◽  
pp. 551-555
Author(s):  
Sureerat Namwong ◽  
Vittaya Punsuvon

Biodiesel is derived from triglycerides by transesterification with methanol or ethanol. In this study, used vegetable oil was transesterified with ethanol using sodium methoxide as catalyst. Parameter affecting the process transesterification were investigated follow this detail. The effects of catalyst to oil volume ratio (3-7:100 %v/v), ethanol to oil volume ratio (20-40:100 %v/v), reaction temperature (55-70 °C) and reaction time (15-90 min.) on the percentage conversion of fatty acid ethyl ester (FAEE) and fatty acid methyl ester (FAME). The FAEE and FAME conversion were detected by 1H-NMR. The result showed that the maximum percentages at 84 % of FAEE and 16 % of FAME were obtained. These conversions were obtained at the catalyst to oil volume ratio of 4:100 %v/v, ethanol to oil volume ratio of 35:100 %v/v, temperature of 65 °C and reaction time of 75 min. The properties of mixed FAEE and FAME biodiesel were within the limits of EN standard. The confirmation result by 1H-NMR and ATR-FTIR also indicated the conversion of used vegetable oil into biodiesel.


1999 ◽  
Vol 122 (4) ◽  
pp. 588-595 ◽  
Author(s):  
Laura M. Ricart ◽  
Rolf D. Reltz ◽  
John E. Dec

The performance of two spray models for predicting liquid and vapor fuel distribution, combustion and emissions is investigated. The model predictions are compared with extensive data from in-cylinder laser diagnostics carried out in an optically accessible heavy-duty, D. I. diesel engine over a wide range of operating conditions. Top-dead-center temperature and density were varied between 800 K and 1100 K and 11.1 and 33.2 kg/m3, respectively. Two spray breakup mechanisms were considered: due to Kelvin-Helmholtz (KH) instabilities and to Rayleigh-Taylor (RT) instabilities. Comparisons of a wide range of parameters, which include in-cylinder pressure, apparent heat release rate, liquid fuel penetration, vapor distribution and soot distribution, have shown that a combination of the KH and the RT mechanisms gives realistic predictions. In particular, the limited liquid fuel penetration observed experimentally was captured by including these two competing mechanisms in the spray model. Furthermore, the penetration of the vapor fuel ahead of the liquid spray was also captured. A region of high soot concentration at the spray tip was observed experimentally and also predicted by the KH-RT spray breakup model. [S0742-4795(00)01504-0]


2016 ◽  
Vol 138 (5) ◽  
Author(s):  
Kaushik Saha ◽  
Sibendu Som ◽  
Michele Battistoni ◽  
Yanheng Li ◽  
Shaoping Quan ◽  
...  

A numerical study of two-phase flow inside the nozzle holes and the issuing spray jets for a multihole direct injection gasoline injector has been presented in this work. The injector geometry is representative of the Spray G nozzle, an eight-hole counterbore injector, from the engine combustion network (ECN). Simulations have been carried out for a fixed needle lift. The effects of turbulence, compressibility, and noncondensable gases have been considered in this work. Standard k–ε turbulence model has been used to model the turbulence. Homogeneous relaxation model (HRM) coupled with volume of fluid (VOF) approach has been utilized to capture the phase-change phenomena inside and outside the injector nozzle. Three different boundary conditions for the outlet domain have been imposed to examine nonflashing and evaporative, nonflashing and nonevaporative, and flashing conditions. Noticeable hole-to-hole variations have been observed in terms of mass flow rates for all the holes under all the operating conditions considered in this study. Inside the nozzle holes mild cavitationlike and in the near-nozzle region flash-boiling phenomena have been predicted when liquid fuel is subjected to superheated ambiance. Under favorable conditions, considerable flashing has been observed in the near-nozzle regions. An enormous volume is occupied by the gasoline vapor, formed by the flash boiling of superheated liquid fuel. Large outlet domain connecting the exits of the holes and the pressure outlet boundary appeared to be necessary leading to substantial computational cost. Volume-averaging instead of mass-averaging is observed to be more effective, especially for finer mesh resolutions.


Sign in / Sign up

Export Citation Format

Share Document