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The current study was conducted to estimate and identify Fe-doped activated carbon synthesized from empty date palm bunch fibers that may be used for furfural efficient removal. The prepared adsorbent was identified by scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy techniques. The capability of the modified adsorbent for furfural elimination in synthetic wastewater of the Al-Doura oil refinery in Baghdad city was estimated through both kinetic and equilibrium studies with investigating the key parameters such as adsorbent loading, contact time, furfural loading, initial pH, and mixing speed. Experimental results showed that after 125 min of contact time a percentage removal efficiency of 80% and 58% with absorption capacities of 27.04 and 16.80 mg·g-1 was attained by using Fe-doped activated carbon, and activated carbon, respectively at optimum initial pH of 6. Results showed that the pseudo-first-order fitted well with the system kinetics. Moreover, the Langmuir isotherm model agreed well with the adsorption equilibrium system. The thermodynamic study revealed that the negative value of G marks the spontaneity and feasibility of the sorption operation. A regression model was developed for the percentage removal of furfural as a function of operating parameters with a correlation coefficient of 0.9875 and a standard of deviation = 1.18%. [ABSTRACT FROM AUTHOR]

The effectiveness and performance of industrial hydro-processing Ebullated Bed Reactors (EBRs) are highly dependent on the bed hydrodynamics and operating conditions. In present work, hydrodynamics of EBRs was studied in a cold model experimental setup using air–water–solid particles system. Pressure gradient method and Residence Time Distribution (RTD) technique were used to estimate the individual holdups, and dispersion coefficients in the lab-scale ebullated bed column. System Hydraulic Efficiency (HEF) was also estimated. The results showed that liquid internal recycle ratio, which characterized the EBRs, has a predominant effect on the individual holdups and dispersion coefficients. Empirical correlations were developed for prediction of phase holdups, and dispersion coefficients with good accuracy.

Study has shown that the precipitation of asphaltenes could be the most detrimental mechanism that significantly influences well productivity during crude oil processing. The flow of the crude oil could seriously be affected if the effect of the asphaltenes is not inhibited. This study aims to investigate the effect of TiO2-based nanofluid in stabilizing crude oil flow. The effect of the ratio of TiO2/SiO2 nanocomposite in the organic nanofluid, the salinity of the nanofluid, and pH on the amount of organic solvent (n-heptane) added to stabilize the crude oil flow was investigated using Gaussian Process Progression (GPR) with five kernel functions [exponential square kernel (model 1), rotational quadratic (model 2), Matern 5/2 (model 3), exponential (model 4), and non-isotopic rotational quadratic (model 5)]. The GPR using the various kernel function had good modeling of the relationship between the ratio of TiO2/SiO2 nanocomposite in the organic nanofluid, the salinity of the nanofluid, the pH, and the amount of organic solvent (n-heptane) added to stabilize the crude oil flow. This is evidence from the R2 of 0.820, 0.999, 0.999, 0.999, 0.999 for model 1, model 2, model 3, model 4, and model 5, respectively. Each of the models had low prediction errors as indicated by the MSE, RMSE, and MAE. Based on the sensitivity analysis, the ratio of TiO2/SiO2 nanocomposite in the organic nanofluid had the most significant influence on the amount of n-heptane added to stabilize the crude oil. [ABSTRACT FROM AUTHOR]

Published data on the hydrodynamics of ebullated- bed reactors (EBRs) used in the H-Oil process are scarce. In the present work, the effect of solid properties (e.g., particle sire, and degree of hydrophobicity) on the hydrodynamics and foaminess in a lab-scale cold model of an (EBR) was investigated. 20wt. % MgS04 solution was utilized as the liquid phase to imitate the hydrodynamic trends in the industrial-scale EBR of the hydro-conversion process. Experimental results depicted that the flow regime of the multiphase system can be readily evaluated by using the pressure drop technique. The turning from the bubbly to the turbulent system is enhanced with diminishing particle size, and decreasing particle hydrophobicity. Moreover, the degree of particle hydrophobicity was inversely proportional to the average gas holdup in the EBR The reduction in average gas holdup was 7 .9 % using hydrophobic particles more than that of the hydrophilic one. In the EBR, it was found that bubble sizes were increased with both gas velocity and the axial location far from the gas distributor while liquid velocity has negative impact on bubble sire. The experimental work revealed that hydrophobic particles of smaller sire (250 µrm) reduced foaming by 70% using 20 vol. % of solid loading and gas and liquid velocities of 10 and 0.15 cm s-1, respectively. This outcome revealed that the surface of catalyst particles used can be modified to act as foaminess-reducer in fluidized bed hydro conversion reactors. [ABSTRACT FROM AUTHOR]

In present work, the removal of vanadium (V) from Iraqi crude oil using zeolite A was investigated. Different operating parameters such as adsorbent loading, vanadium loading, and operating time were studied for their effects on metal removal efficiency. Results of the adsorption test showed that the Langmuir isotherm predicted well the experimental data and the maximum zeolite A uptake was 30 mg V/1 g zeolite. XRD, SEM, and EDX analyses revealed the noticeable uptake of zeolite for V. In crude oil, experimental results indicated that for zeolite loading at 1 g/100 mL oil and within approximately 5 h, the removal efficiencies of V were 60, 45, and 33% at vanadium loadings of 75, 85, and 95 ppm respectively. While at 10, 20, 40, and 50 h the removal efficiency was 68, 75, 78 and 78% at 75 ppm of vanadium loading. At vanadium loading of 75 ppm, the equilibrium concentration of V in crude oil was obtained after 40 h of operation. Long-term tests revealed the high stability of zeolite A for vanadium removal. Experimental results depicted that zeolite A could be advantageous for the removal of V in the crude oil hydrotreating units. [ABSTRACT FROM AUTHOR]

The present work was devoted to investigate the kinetic behavior of an industrial-scale ebullated bed reactor, licensed by Axens Co., in Lukoil refinery at Bourgas, Bulgaria. Another objective of the present work is to formulate a steady state mathematical model to predict the profile of products along the reactor, and to investigate effects of the operating variables [e.g., operating temperature, weight hour space velocity (WHSV), and reaction time] on the kinetic parameters, and performance of the industrial ebullated bed reactor. A five-lump kinetic model was utilized to describe the catalytic hydrocracking of heavy oil and to formulate the reaction rate equations of the main components of heavy oil. The formulated model was validated by comparing its outcome with experimental measurements of fractions of VR, VGO, and N at the effluent of industrial reactor against residence time. Results revealed an opposite relationship of the effectiveness factor with both temperature and WHSV. Results showed that the activation and deactivation energies were approximately equal, indicating that catalyst deactivation has no appreciable effect on the hydrocracking reactions in the ebullated bed reactor. The hydrocracking reactions of vacuum residue to lower molecular weight components are preferentially obtained in the following descending order: VGO; middle distillates; naphtha; gases. WHSV has a negative effect on the yield of the industrial reactor while the trend was different with the operating temperature. Outcomes of the formulated model were compared with the data reported in the literature. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the feasibility of hydrodesulfurization (HDS) of a mixture of crude oil fractions (e.g., naphtha, kerosene, and gas oil) all in one time in a single reactor loaded with NiCoMo/Al2O3 under various operating parameters such as temperature (310-370∘C), pressure (40-55 bars), weight hour space velocity (1.2—3.6h-1), and hydrogen-to-hydrocarbon ratio (150-300 vol/vol). Experimental results showed that temperature and pressure have positive effects on process performance while weight hour space velocity gives a different trend. Optimum operating conditions (i.e., 350∘C, 50bars,1.2h-1, and 200 vol/vol) with the theoretical and experimental values of HDS efficiency of 95.4 and 95.8%, respectively, were estimated using advance statistical software DESIGN-EXPERT 10.0.6.0. Reaction products were fractionated and analyzed for comparing with products of the conventional HDS method. An approximate evaluation of the proposed system indicated a 60% reduction in fixed capital cost compared to that for conventional hydrotreatment system. The experimental analysis revealed the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the intrinsic reaction of hydrodesulfurization (HDS) for a real Straight Run Heavy Naphtha (SRHN) over CoMo-S/Al2O3 catalyst in a fixed- bed reactor. Influence of the process parameters on sulfur removal was investigated by regulating the temperature (T = 320-380 oC), pressure (P = 20 to 35 bar), weight hour space velocity (WHSV = 2.5 to 5.0 h-1) and catalyst average particle size (dp =361 to 3950 μm). Mears and Weisz-Prater criteria were estimated and utilized to validate the intrinsic reaction condition. Operating variables were optimized at (T = 360 oC, P = 30 bars, WHSV = 2.5 h-1, dp= 361 μm) to obtain an optimum sulfur removal of 93.4% under intrinsic reaction conditions. Experimental results showed that % activity of sulfur removal increases to 93.4% as temperature increased to 360oC but it reduces to 90.3% as space velocity increased to 5.0 h-1. Kinetic parameters of the intrinsic reaction rate were estimated and compared with published data. Long-time test was performed on the sulfided catalyst to investigate its activity. [ABSTRACT FROM AUTHOR]

Catalytic wet oxidation (CWO) of phenol was studied in the present work. The effect of liquid hourly space velocity (LHSV), superficial gas velocity, reactor pressure, temperature and initial phenol concentration on phenols removal was investigated. Results showed that phenol conversion increased with increasing reaction temperature, reactor pressure, and superficial gas velocity of oxygen, yet it decreased with increasing (LHSV). The results exhibited that the highest phenol conversion of (67.47%) was obtained over 0.5% Pt/γ-Al2O3 at the studied reaction conditions (i.e., operating pressure = 0.6 MPa, operating temperature = 140°C, LHSV = 4 h-1, and gas superficial velocity = 0.169 m/s), with phenol concentration = 900 mg/L. According to the kinetic results, the reaction behavior was first order with respect to phenol concentration, (0.69) order with respect to oxygen and the activation energy was equal to (29.299) kJ/mol. Selectivity maps for concentration of intermediate compounds in reactor effluent were introduced which would be helpful for monitoring the reaction pathways of phenol oxidation. [ABSTRACT FROM AUTHOR]