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Articles 331 - 360 of 491

Full-Text Articles in Chemical Engineering

A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos Jan 2010

A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos

LSU Master's Theses

An university-industry consortium has been studying alternative well control procedures to be used for kicks taken during managed pressure drilling (MPD) operations using the constant bottom hole pressure (CBHP) method. The CBHP method of MPD allows more precise control of wellbore pressure than conventional drilling. MPD surface equipment allows more alternatives for controlling a kick and may support faster detection of kicks and losses which can reduce the severity of a well control event. Nevertheless, the elimination of well control incidents cannot be guaranteed, and the uncertainty in downhole drilling margins are not reduced by adopting MPD methods. The primary …


Surfactant-Induced Flow Behavior Effects In Gas Condensate Reservoirs, Bikash Deep. Saikia Jan 2010

Surfactant-Induced Flow Behavior Effects In Gas Condensate Reservoirs, Bikash Deep. Saikia

LSU Master's Theses

Natural gas, which accounts for a quarter of world’s energy, has been a major energy source because of its abundance and less impact on environment. With explorations at higher depth, pressure and temperature, the share of gas condensate reservoirs to global gas production is increasing. A unique production challenge associated with these reservoirs is the condensate blockage problem, which is the buildup of condensate liquid saturation around wellbore as a result of drawdown below dew point pressure. Mitigation of this problem requires in depth understanding of the multiphase flow of liquid and gas. Surfactants are well known in the literature …


Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya Jan 2010

Experimental Study On Single Cement Fracture Exposed To Co2 Saturated Brine Under Dynamic Conditions, Tevfik Yalcinkaya

LSU Master's Theses

Carbon capture and storage is one of the technologies that could help reduce CO2 concentration in the atmosphere while contributing to cutback of Greenhouse Gas emissions. Depleted oil and gas fields are favorable targets for CO2 storage because existing wells can be readily used as injection wells. However, a number of abandoned wells also serve as gateway to the reservoir which should be considered in the context of effective Carbon capture and storage. Wellbore cement is a very essential element in wellbore systems that serve as a barrier between different zones in the subsurface. The fractures inside wellbore cement sheath, …


Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu Jan 2010

Catalytic Oxidative Desulfurization Of A Model Diesel, Dongxing Liu

LSU Major Papers

An analysis of heterogeneous oxidation catalysts was performed to determine the activities and optimal operating conditions for the multiphase oxidative desulfurization (ODS) reactions, using a model diesel. Catalysts studied included well-characterized Pd on Al2O3 and activated carbon supports, and carbon-supported Mo2C and W2C, which were prepared by temperature programmed reaction. Several other typical oxidation catalysts were also examined. The model diesel consisted of ~1 wt% sulfur compounds (thiophene and dibenzothiophene) with appropriate amounts of aliphatic, alkylaromatic and N-heterocyclic compounds to simulate a raw number 2 diesel. With oxygen as the oxidant in ODS reactions of this model diesel (70-90ºC, 0.8-1.8 …


Electrodeposited Cu-Based Catalysts For Alcohols From Co Hydrogenation And Electrodeposition Of Cuniw/Cuni Multilayered Alloys, Mayank Gupta Jan 2010

Electrodeposited Cu-Based Catalysts For Alcohols From Co Hydrogenation And Electrodeposition Of Cuniw/Cuni Multilayered Alloys, Mayank Gupta

LSU Doctoral Dissertations

Ethanol and higher alcohols can be used as a fuel or fuel additive in gasoline engines as well as a hydrogen carrier. One of the promising methods to synthesize these alcohols is based on thermochemical conversion of CO and H2 (CO hydrogenation). Conventional catalysts used for the conversion CO and H2 (syngas) to ethanol typically give yields less than 20% with the balance resulting mostly in the formation of the thermodynamically favored products CH4 and CO2. New catalysts with compositions designed to kinetically favor the formation of ethanol and higher alcohols are needed. Electrodeposition of nanowires offers a means to …


X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos Jan 2010

X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos

LSU Doctoral Dissertations

Synthetic fuels derived from methane, coal or biomass are essential in addressing future transportation fuel demands which are expected to exceed petroleum-derived capacities. The Fischer-Tropsch synthesis (FTS) is the most studied technique for the conversion of coal or biomass-derived syngas into transportation fuels. Fe-based catalysts are typically used for the FTS of biomass and/or coal-derived syngas due to: the relatively low cost of iron, water-gas shift activity, and low methane selectivity at industrial FTS conditions. Fe/Cu/SiO2 Fischer-Tropsch catalysts promoted with Cr, Mn, Mo, W, or Zr were studied in-situ, using Fe K-edge TPR XANES (temperature programmed reduction X-ray absorption near-edge …


Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee Jan 2010

Modeling And Multiresolution Characterization Of Micro/Nano Surface For Novel Tailored Nanostructures, Rajib Mukherjee

LSU Doctoral Dissertations

Nanofabrication is state of the art technology. Various chemical, mechanical, biochemical and semiconductor products have characteristics controlled by the nanostructures of the surface and interphase. Surface microscopic imaging is generally used to capture different surface features. By properly analyzing the surface image, valuable information regarding manufacturing process and product performance can be extracted. While microscopy measurements can offer very accurate qualitative information about surface features, for many applications, it is critical to obtain a quantitative description of the surface morphology. Various statistical features can be used to characterize the surface in quantitative way. Such an analysis can be done by …


Transient Study Of The Wetting Films In Porous Media Using 3d X-Ray Computed Micro-Tomography: Effect Of Imbibition Rate And Pore Geometry, Pradeep Bhattad Jan 2010

Transient Study Of The Wetting Films In Porous Media Using 3d X-Ray Computed Micro-Tomography: Effect Of Imbibition Rate And Pore Geometry, Pradeep Bhattad

LSU Doctoral Dissertations

Imbibition in porous media is governed by the complex interplay between viscous and capillary forces, pore structure and fluid properties. Understanding and predicting imbibition is important in many natural and engineered applications; it affects the efficiency of oil production operations, the moisture and contaminant transport in soil science, and the formation of defects in certain types of composite materials. Majority of the studies published on the transient imbibition behavior in a porous medium were conducted in the simplified 2D transparent micromodels or the 2D projection visualization (X-ray or visible light) of the 3D porous medium. However, the pore level transient …


Characterization Of Rock/Fluids Interactions At Reservoir Conditions, Dayanand Saini Jan 2010

Characterization Of Rock/Fluids Interactions At Reservoir Conditions, Dayanand Saini

LSU Doctoral Dissertations

In this study, interfacial phenomena of spreading, wettability, and rock/oil adhesion interactions in complex rock/oil/water systems were characterized at reservoir conditions of elevated pressures and temperatures. Capabilities of both ambient and reservoir condition optical cells were used for measuring the oil/water interfacial tension and dynamic (the water-receding and the water-advancing) contact angles for various complex rock/oil/water systems. Well known sessile oil drop volume alteration method was successfully used in this study for evaluating the applicability of the modified Young’s equation for characterizing the line tension in complex rock/oil/water systems at reservoir conditions. This appears to be first time when rock/fluids …


Designing A Whey Protein Based Material As A Scaffold For Bone Regeneration, Mia Dvora Jan 2010

Designing A Whey Protein Based Material As A Scaffold For Bone Regeneration, Mia Dvora

LSU Doctoral Dissertations

A novel gel material was designed and optimized for use as a bone tissue regeneration scaffold. Whey protein isolate (WPI), the primary component of the material, underwent considerable testing for conformity to a set of known material characteristics required for application in bone regeneration. WPI gels of different compositions were fabricated by thermally inducing gelation of high-concentration protein suspensions, and characterized for compressive strength and modulus, hydration swelling and drying properties, mechanical behavior change due to polysaccharide additives, and intrinsic pore network structure. The gels were also tested for their compatibility with MC3T3-E1 cells, and interactions such as cell adhesion, …


Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta Jan 2010

Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta

LSU Doctoral Dissertations

The objective of this research is to propose, develop and demonstrate a methodology for the optimal integration of bioprocesses in an existing chemical production complex. Chemical complex optimization is determining the optimal configuration of chemical plants in a superstructure of possible plants based on economic, environmental and sustainable criteria objective function (triple bottomline) and solves a mixed integer non linear programming problem. This research demonstrated the transition of production of chemicals from non-renewable to renewable feedstock. A conceptual design of biochemical processes was converted to five industrial scale designs in Aspen HYSYS® process simulator. Fourteen input-output block models were created …


Supercritical Pyrolysis Of N-Decane, Sean Bagley Jan 2010

Supercritical Pyrolysis Of N-Decane, Sean Bagley

LSU Doctoral Dissertations

Fuels used in future generations of high-speed jet aircraft will be required to take on increasing heat loads in their role as the primary coolant for the absorption of waste heat from the engine. As a consequence, the hydrocarbon fuels will be exposed to elevated temperatures and pressures prior to their use as fuels, conditions which are beyond the critical point of the fuel and which lead to the formation of carbonaceous solid deposits in the pre-combustion environment.

Deposition of solids causes reduced engine performance and eventual failure, so understanding the mechanisms by which thermally stressed hydrocarbons become solids is …


Downhole Water Loop (Dwl) Well Completion For Water Coning Control --- Theoretical Analysis, Lu Jin Jan 2009

Downhole Water Loop (Dwl) Well Completion For Water Coning Control --- Theoretical Analysis, Lu Jin

LSU Master's Theses

The Thesis is an analytical and numerical analysis of a new method for completing and producing oil wells affected by water coning. The method enables producing oil with no or minimal water cut while keeping the water subsurface with downhole water loop (DWL) installation. Typically, a DWL well is triple-completed in the oil and water zones with the three completions separated by parkers. The top completion produces oil to the surface while the middle and bottom completions drain from and inject into the bottom water zone, respectively. Segregated-inflow operation of DWL well requires keeping the production and drainage-injection rates below …


Evaluation Of Interwell Connectivity Of Little Creek Field, Mississipii [Sic] From Production Data, Gbemisola Yewande Ogunyomi Jan 2009

Evaluation Of Interwell Connectivity Of Little Creek Field, Mississipii [Sic] From Production Data, Gbemisola Yewande Ogunyomi

LSU Master's Theses

The understanding of geological characteristics and heterogeneity of a reservoir enables better decisions for reservoir development. Statistical methods use universally available injection and production rate data to help evaluate reservoir characteristics and behavior.In this research project, statistical methods typically used to infer communication between injector-producer well pairs in a waterflood reservoir using only production and injection rate data are applied to a CO2 flood. The multivariate linear regression (MLR) technique computes weighting coefficients possibly related to the fraction of the flow in a producer that comes from each of the injectors (Albertoni and Lake, 2002). MLR was applied to the …


The Development Of A Pore Pressure And Fracture Gradient Prediction Model For The Ewing Banks 910 Area In The Gulf Of Mexico, Jeffrey Steven Fooshee Jan 2009

The Development Of A Pore Pressure And Fracture Gradient Prediction Model For The Ewing Banks 910 Area In The Gulf Of Mexico, Jeffrey Steven Fooshee

LSU Master's Theses

The purpose of this project is to develop a pore pressure and fracture gradient prediction strategy for the Ewing Banks 910 (EW 910) area. Petrophysical and measured pressure data for eight wells previously drilled in the EW 910 area will be examined and reviewed. This strategy will help design future drilling and completion operations in the aforementioned area. Two pore pressure prediction strategies and one fracture gradient prediction strategy will be reviewed and applied to the available data. The first pore pressure prediction strategy reviewed was developed by W. R. Matthews. This strategy utilizes a geologic age specific overlay which …


Mechanistic Foam Modeling And Simulations: Gas Injection During Surfactant-Alternating-Gas Processes Using Foam-Catastrophe Theory, Ali Afsharpoor Jan 2009

Mechanistic Foam Modeling And Simulations: Gas Injection During Surfactant-Alternating-Gas Processes Using Foam-Catastrophe Theory, Ali Afsharpoor

LSU Master's Theses

The use of foam for mobility control is a promising means to improve sweep efficiency in subsurface applications such as improved/enhanced oil recovery and aquifer remediation. Foam can be introduced into geological formations by injecting gas and surfactant solutions simultaneously or alternatively. Alternating gas and surfactant solutions, which is often referred to as surfactant-alternating-gas (SAG) process, is known to effectively create fine-textured strong foams due to fluctuation in capillary pressure. Recent studies show that foam rheology in porous media can be characterized by foam-catastrophe theory which exhibits three foam states (weak-foam, strong-foam, and intermediate states) and two strong-foam regimes (high-quality …


Realtime Reservoir Characterization And Beyond: Cyber-Infrastructure Tools And Technologies, Yaakoub Youssef El-Khamra Jan 2009

Realtime Reservoir Characterization And Beyond: Cyber-Infrastructure Tools And Technologies, Yaakoub Youssef El-Khamra

LSU Master's Theses

The advent of the digital oil _x000C_eld and rapidly decreasing cost of computing creates opportunities as well as challenges in simulation based reservoir studies, in particular, real-time reservoir characterization and optimization. One challenge our e_x000B_orts are directed toward is the use of real-time production data to perform live reservoir characterization using high throughput, high performance computing environments. To that end we developed the required tools of parallel reservoir simulator, parallel ensemble Kalman _x000C_lter and a scalable work ow manager. When using this collection of tools, a reservoir modeler is able to perform large scale reservoir management studies in short periods …


Sialic Acid Conjugated Chitosan For The Attenuation Of Amyloid-Beta Toxicity, Dhruva Dilip Dhavale Jan 2009

Sialic Acid Conjugated Chitosan For The Attenuation Of Amyloid-Beta Toxicity, Dhruva Dilip Dhavale

LSU Master's Theses

Amyloid-beta (Aβ), a 39 to 43 amino acid long peptide, is the primary species identified in senile plaques associated with Alzheimer’s disease (AD) and has been implicated in the neurotoxicity associated with AD. It is believed that Aβ toxicity is mediated through the interaction with neuronal membranes. A variety of evidence indicates that 1) Aβ may bind to the cell surface sialic acids, 2) the affinity of this interaction is higher if the gangliosides or sialic acids on the cell surface are clustered, 3) the removal of the surface sialic acids attenuate Aβ toxicity. Based on this data, we hypothesized …


Framework For Operability Assessment Of Production Facilities: An Application To A Primary Unit Of A Crude Oil Refinery, Sampath Yela Jan 2009

Framework For Operability Assessment Of Production Facilities: An Application To A Primary Unit Of A Crude Oil Refinery, Sampath Yela

LSU Master's Theses

This work focuses on the development of a methodology for the optimization, control and operability of both existing and new production facilities through an integrated environment of different technologies like process simulation, optimization and control systems. Such an integrated environment not only creates opportunities for op¬erational decision making but also serves as training tool for the novice engineers. It enables them to apply engineering expertise to solve challenges unique to the process industries in a safe and virtual environment and also assist them to get familiarize with the existing control systems and to understand the fundamentals of the plant operation. …


Assessment Of Target Purity Difference For A Louisiana Sugar Mill, Luz Stella Polanco Jan 2009

Assessment Of Target Purity Difference For A Louisiana Sugar Mill, Luz Stella Polanco

LSU Master's Theses

The main goals of a “raw” sugarcane factory are to have an efficient profitable operation with the required sugar quality and maximum sugar recovery. The loss of sugar to final molasses accounts for 45 to 47% of the total sugar losses. An estimation of the average cost of the manufacturing losses for the 2007 harvest season was approximately $9 million – the sugar lost to the final molasses accounts for approximately 50% of this cost (Salassi, 2008). For final molasses, the “Target Purity” (or equilibrium purity) refers to the minimum level of sucrose that theoretically remains in solution for a …


Supercritical Pyrolysis Of 1-Methylnaphthalene, Michelle Somers Walker Jan 2009

Supercritical Pyrolysis Of 1-Methylnaphthalene, Michelle Somers Walker

LSU Doctoral Dissertations

Fuels used in future high-speed jet aircraft will act as coolants to absorb excess heat produced by the engine, exposing the fuel to elevated temperatures and pressures beyond the fuel’s critical point before entering the combustion environment. Fuels used in this capacity are subject to pyrolysis reactions in the supercritical environment, forming polycyclic aromatic hydrocarbons (PAH) and eventually carbonaceous solids, a disastrous effect for aircraft operation. Thus, it is important to understand how different components of jet fuel will react in the supercritical pyrolysis environment, particularly if their reactions will lead to PAH and/or carbonaceous solids. To better understand these …


A Simulation-Based Evaluation Of Alternative Initial Responses To Gas Kicks During Managed Pressure Drilling Operations, Majid Davoudi Jan 2009

A Simulation-Based Evaluation Of Alternative Initial Responses To Gas Kicks During Managed Pressure Drilling Operations, Majid Davoudi

LSU Master's Theses

Managed pressure drilling (MPD) is an adaptation of conventional drilling that has been developed to manage and control subsurface pressures in the well in order to minimize specific drilling problems. The constant bottom hole pressure approach (CBHP) is a versatile method of MPD, where a closed annulus allows initial responses to kicks other than simply shutting in the well. The objective of this research was to identify and evaluate the best initial response to gas kicks taken during drilling as a basis for developing reliable well control procedures for CBHP operations. Nine non-circulating and circulating responses (NCRs and CRs) were …


Simulation Study Of Emerging Well Control Methods For Influxes Caused By Bottomhole Pressure Fluctuations During Managed Pressure Drilling, Hakan Guner Jan 2009

Simulation Study Of Emerging Well Control Methods For Influxes Caused By Bottomhole Pressure Fluctuations During Managed Pressure Drilling, Hakan Guner

LSU Master's Theses

Managed Pressure Drilling (MPD) is an emerging drilling technology that utilizes mud weight, surface backpressure and annular frictional pressure loss (AFP) to precisely control the wellbore pressure. The goal of this project is to identify the most appropriate initial response and kick circulation method for the kicks that result from complications specific to MPD. These complications that can cause a reduction in bottomhole pressure were classified as surface equipment failures and unintended equivalent circulating density (ECD) reductions. Rotating control device (RCD) and pump failures are the examples of surface equipment failures. Pump efficiency loss and BHA position change represent the …


Progressive Water-Oil Transition Zone Due To Transverse Mixing Near Wells, Shengkai Duan Jan 2009

Progressive Water-Oil Transition Zone Due To Transverse Mixing Near Wells, Shengkai Duan

LSU Doctoral Dissertations

This study derives from observations made in petroleum research and practices of chemical industry that efficient mixing takes place in segregated immiscible fluid flow in granular packs and static mixers. A hypothesis was formulated that transverse mixing (TM) across oil-water interface may occur in segregated inflow to wells resulting in progressive transition zone, more water production, and reduced oil productivity. “Mixing” is broadly interpreted here to address the entire range of stirring, splitting, dispersion and diffusion processes between two fluids.

Initial study showed that a commercial reservoir simulator would not model any transition zone in segregated oil-water flow at high …


Photocatalytic Reaction In Monolithic Optical Fiber Reactor With Inverse Opal Catalyst, Maoming Ren Jan 2009

Photocatalytic Reaction In Monolithic Optical Fiber Reactor With Inverse Opal Catalyst, Maoming Ren

LSU Doctoral Dissertations

The development of photocatalytic reactor is essential for the successful application of heterogeneous semiconductor in environmental study, which has been shown to be photoactive and effective to oxidate organic pollutant and photoreduce CO2 to useful compounds. In this dissertation, a monolithic optical fiber reactor (MOFR) coated with inverse opal titania, which uses optical fibers as light-transmitting conductor and support of catalyst, was developed for both photodegradation and photoreduction. 1,2-dichlorobenzene, a volatile organic compound (VOC), was selected as the organic pollutant. This configuration of reactor and catalyst provides a high surface area, enhances mass transfer within the catalyst, manipulates photons transmission …


Integrated Model-Centric Decision Support System For Process Industries, Daira Aragon Jan 2009

Integrated Model-Centric Decision Support System For Process Industries, Daira Aragon

LSU Doctoral Dissertations

To bring the advances in modeling, simulation and optimization environments (MSOEs), open-software architectures, and information technology closer to process industries, novel mechanisms and advanced software tools must be devised to simplify the definition of complex model-based problems. Synergistic interactions between complementary model-based software tools must be refined to unlock the potential of model-centric technologies in industries. This dissertation presents the conceptual definition of a single and consistent framework for integrated process decision support (IMCPSS) to facilitate the realistic formulation of related model-based engineering problems. Through the integration of data management, simulation, parameter estimation, data reconciliation, and optimization methods, this framework …


Particle-Chemical Interactions And Environmental Chemodynamics Of Fine And Ultrafine Particles In A Natural Disaster Scenario, Nicholas A. Ashley Jan 2009

Particle-Chemical Interactions And Environmental Chemodynamics Of Fine And Ultrafine Particles In A Natural Disaster Scenario, Nicholas A. Ashley

LSU Doctoral Dissertations

The interactions of fine and ultrafine particles with chemicals play a dominant role in determining the mobility and availability of pollutants in the environment. Fine particles in sediments can sequester chemicals from the water column, and release volatile and semi-volatile organic compounds to the gas phase upon exposure to air. Ultrafine particles which are photoreactive can degrade these vapor-phase contaminants, and may transform the molecules into species which are more toxic or hazardous than the parent. As the widespread, commercial use of ultrafine particles becomes more common, understanding the chemodynamics of these particles and their interactions with chemicals in the …


The Effects Of Inorganic Solids And Certain Gases On The Thermal Decomposition Of Catechol, Jerome Apilan Robles Jan 2009

The Effects Of Inorganic Solids And Certain Gases On The Thermal Decomposition Of Catechol, Jerome Apilan Robles

LSU Doctoral Dissertations

In order to investigate the effects of calcium carbonate and iron oxide on the thermal decomposition of solid fuels, we have constructed an isothermal flow reactor to perform experiments on the model compound catechol (ortho-dihydroxybenzene), a phenol-type compound representative of coal, wood and biomass. Calcium carbonate and iron oxide are inorganic components of coal and wood, which have demonstrated catalytic properties in thermal reactions and are commercially used to enhance the conversion of solid fuels. In this study, the effects of the inorganic solids on pyrolysis and combustion are conducted through identification and quantification of the products formed after subjecting …


Integrated Data-Driven Techniques For Environmental Pollution Monitoring, Swathi Pakalapati Jan 2009

Integrated Data-Driven Techniques For Environmental Pollution Monitoring, Swathi Pakalapati

LSU Doctoral Dissertations

The adverse health e_x000B_ffects of tropospheric ozone around urban zones indicate a substantial risk for many segments of the population. This necessitates the short term forecast in order to take evasive action on days conducive to ozone formation. Therefore it is important to study the ozone formation mechanisms and predict the ozone levels in a geographic region. Multivariate statistical techniques provide a very e_x000B_ffective framework for the classifi_x000C_cation and monitoring of systems with multiple variables. Cluster analysis, sequence analysis and hidden Markov models (HMMs) are statistical methods which have been used in a wide range of studies to model the …


Sulphur Removal Using Regenerable Sorbents Of Rare Earth/Transition Metal Oxides, Vikram Reddy Kalakota Jan 2008

Sulphur Removal Using Regenerable Sorbents Of Rare Earth/Transition Metal Oxides, Vikram Reddy Kalakota

LSU Master's Theses

Hot gas desulfurization of gases from primary gasifier can be accomplished using sorbents composed Zn, calcium and transition metal oxide sorbents. The problem with metal oxide sorbents alone is that they are easily reduced at high temperature above 873 K to metallic state under reducing atmosphere decreasing their desulfurization capacity. Sorbents studied for hot gas desulfurization were based on Ce/La/M (M = transition metal) oxides and Ce/La/RE (RE = a rare earth) oxide. Sorbents were prepared using sol-gel method and the rare earth oxides were doped with transition metals using incipient wetness impregnation. Sulfidation experiments were carried out at 873 …