19 research outputs found
Amphipathic anionic surfactant modified hydrophilic polyethylene glycol-nanosilica composite as effective viscosifier and filtration control agent for water-based drilling muds
Highly stabilized and dispersible composites of polyethylene glycol and silica nanoparticle in aqueous drilling mud can provide desirable rheological and filtration properties for drilling jobs. Therefore, high-quality hydrophilic polyethylene glycol-nanosilica composite modified by amphipathic anionic sodium dodecyl sulfate (PEG-SiO2 NC-SDS) to improve the rheological and filtration properties of water-based muds (WBMs) was submitted. Test of zeta potential, functional groups, morphology, elemental composition, and temperature stability together with rheology and filtration tests were undertaken to assess the wide-ranging mud properties of the SDS modified PEG-SiO2 NC drilling muds. Zeta potential, FTIR, FESEM, EDX, and TGA results indicate that the SDS modified PEG-SiO2 NC was effectively formed and modified, it embodies exceptional thermal stability and is efficiently dispersed. The SDS modified PEG-SiO2 NC has a narrow size distribution range between 82 nm and 410 nm, and a specific surface area of 41.4 m2/g that is sufficiently high for particle-molecule interactions. Its rheological variables are notably shear-thinning and did not undergo notable fluctuation. The filtrate loss of 1.5 g SDS bearing PEG-SiO2 NC at 78 °F and 250 °F was only 5.4 ml and 9.6 ml, against 10.2 ml and 20.5 ml of the WBMs, respectively. High dispersion stability and high thermal stability aided its excellent viscosity and filtration control performance. Moreover, optimum rheological properties for the SDS modified PEG-SiO2 NC drilling muds with Bingham plastic and Ostwald-de-Waele models occurred with mud composition CD3 (CD3 = 1.5 g SDS modified PEG-SiO2 NC + WBM). Thus, this study can help to understand the applications of this nanocomposite as a potential viscosifier and filtrate loss control material for WBMs
Charged surface modifying macromolecules in polymer electrolyte membrane
Charged surface modifying macromolecule (cSMM) end capped with sulfonic group was prepared and blended into sulfonated poly (ether ether ketone) (SPEEK). The modified membrane was characterized for polymer electrolyte membrane application; i.e. a SPEEK/cSMM blend membrane was compared to a SPEEK membrane and a Nafion 112 membrane for the thermal and mechanical stability, hydrophilicity and water uptake. Thermal and mechanical stability of the blend membrane were slightly reduced from that of the SPEEK membrane but still higher than that of the Nafion 112 membrane. The blend membrane showed an increase in hydrophilicity and water uptake as compared to the pristine membrane. The addition of cSMM has enabled the water uptake to be increased which is crucial to enhance the proton conductivity that of SPEEK. This study found that cSMM is a good candidate as an additive for SPEEK in improving its
function as polymer electrolyte membrane
Performance Evaluation of of Sulfonated Poly (ether ether ketone) with Charged Surface modifying Macromolecule Membrane in Direct Methanol Fuel Cell
This study focuses on the modification of sulfonated poly(ether ether ketone) (SPEEK) membrane for direct methanol fuel cell application. The modification of SPEEK membrane was attempted by blending charged surface modifying macromolecule (cSMM). The modified membrane was compared with commercial membrane for direct methanol fuel cell (DMFC) application. Thermal and mechanical stability of the blended membrane were slightly reduced from the SPEEK membrane but still higher than the Nafion 112 membrane. The blend membrane was found to be promising for DMFC applications because of its lower methanol diffusivity (2.75Ă10â7 cm2 sâ1) and higher proton conductivity (6.4Ă10â3 S cmâ1), than the SPEEK membrane. The DMFC application testing results was also exhibited that during charging process, the SPEEK membrane could produced the voltage similar with the Nafion membrane.
Keywords: Fuel cell membrane, Nafion Membrane, Direct methanol fuel cell; Proton exchange membrane; Sulfonated poly(ether ether ketone
Preparation and characterization of blending sulfonated poly(ether ether ketone) with charged surface modifying macromolecules
Charged surface modifying macromolecule (cSMM) end capped with sulfonic group was prepared and blended into sulfonated poly(ether ether ketone) (SPEEK). The modified membrane was characterized for polymer electrolyte membrane application; i.e. a SPEEK/cSMM blend membrane was compared to a SPEEK membrane and a Nafion 112 membrane for the thermal and mechanical stability, hydrophilicity and water uptake. Thermal and mechanical stability of the blend membrane were slightly reduced from that of the SPEEK membrane but still higher than that of the Nafion 112 membrane. The cSMM which was endâcapped with sulfonic group has increased the total âSO3H group in the blend membrane. As a result, the blend membrane showed an increase in hydrophilicity and water uptake as compared to the pristine membrane. The addition of cSMM with an additional âSO3â charge has enabled the water uptake to be increased which is crucial to enhance the proton conductivity that of SPEEK. Moreover, the extra âSO3â can facilitate the transfer of proton better. This study found that cSMM is a good candidate as an additive for SPEEK in improving its function as polymer electrolyte membran
Performance Evaluation of of Sulfonated Poly (ether ether ketone) with Charged Surface modifying Macromolecule Membrane in Direct Methanol Fuel Cell
Abstract
This study focuses on the modification of sulfonated poly(ether ether ketone) (SPEEK) membrane for direct methanol fuel cell application. The modification of SPEEK membrane was attempted by blending charged surface modifying macromolecule (cSMM). The modified membrane was compared with commercial membrane for direct methanol fuel cell (DMFC) application. Thermal and mechanical stability of the blended membrane were slightly reduced from the SPEEK membrane but still higher than the Nafion 112 membrane. The blend membrane was found to be promising for DMFC applications because of its lower methanol diffusivity (2.75Ă10â7 cm2 sâ1) and higher proton conductivity (6.4Ă10â3 S cmâ1), than the SPEEK membrane. The DMFC application testing results was also exhibited that during charging process, the SPEEK membrane could produced the voltage similar with the Nafion membrane
Study on catalyst loading using speek/CSMM membrane in DMFC
The purpose of this research is to develop an optimum of anode catalyst loading based on modified sulfonated poly(ether ether ketone) (SPEEK) with charged surface modifying macromolecules (cSMM) membrane. The preparation method of catalyst ink and membrane electrode assembly (MEA) was based on Dr. Blade method and hot pressing by using catalyzed diffusion media (CDM) method. The effect of 30% and 40% PtRu in 2, 4 and 6 mgcm-2 of catalyst loading has been investigated with a fuel cell assembly. The optimization of anode catalyst loading will enhance the DMFC performance. It was found, the best optimal anode catalyst loading was 4 mgcm-2 for this application. Therefore, 4 mgcm-2 is the best catalyst loading
Experimental investigation of cuttings transportation in deviated and horizontal wellbores using polypropylene-nanosilica composite drilling mud
The experience acquired in the field showed that poor cuttings transportation results in several drilling problems, such as pipe sticking, undue torque and drag, holeâpack off, or lower than projected drilling performance. In this study, complex waterâbased mud (WBM) formulated with polypropyleneânanosilica composite (PPâSiO2 NC) and partially hydrolyzed polyacrylamide (PHPA), a dragâreducing agent were used to examine cuttings transferring efficiencies (CTEs). The examination focused on the impact of diameters of cuttings (between 0.50 and 4.00 mm), hole angles (45, 60, 75, 90°), mud velocities (between 0.457 and 1.80 m/s) and different concentrations (0.4, 0.5, 0.8 and 1.2 ppb) of PPâSiO2 NC and PHPA. A fieldâoriented cuttings transport flow loop of dimensions (69.85 mm Ă 26.67 mm, 6.07 mâlong annulus) was constructed to determine the CTEs of the drilling muds. Results showed that smallest cuttings were easiest to remove when mud velocities of 0.457, 0.630, 0.823 and 0.960 m/s were used, but when the velocity increased to 1.80 m/s, the transport of largest cuttings became the easiest. Results also confirmed that PPâSiO2 NC muds are more capable of transferring cuttings than PHPA mud samples with or without pipe rotation speed due to increased colloidal forces that increase the interaction between cuttings and PPâSiOâ NC particles. Rotation of drill pipe and an increase in mud velocity will effectively increase the drag effects, which will lead to increased CTE. Hole angle 45° was the most difficult inclination in the cuttings transport process due to the higher settling tendency of cuttings on the low side of the hole. The application of complex WBM with PPâSiO2 NC showed promising attributes in a cuttings transport process
Characterization and performance of proton exchange membranes for direct methanol fuel cell: Blending of sulfonated poly(ether ether ketone) with charged surface modifying macromolecule
Modification of sulfonated poly(ether ether ketone) (SPEEK) membrane was attempted by blending charged surface modifying macromolecule (cSMM). The modified membrane was tested for direct methanol fuel cell (DMFC) application; i.e. a SPEEK/cSMM blend membrane was compared to a SPEEK
membrane and a Nafion 112 membrane for the thermal and mechanical stability, methanol permeability, and proton conductivity. Thermal and mechanical stability of the blended membrane were slightly reduced from the SPEEK membrane but still higher than the Nafion 112 membrane. The blend membrane was found to be promising for DMFC applications because of its lower methanol diffusivity
(2.75Ăâ10ĂąËâ7 cm2 sĂąËâ1) and higher proton conductivity (6.4Ăâ10ĂąËâ3 ScmĂąËâ1), than the SPEEK membrane. A plausible explanation was given for the favorable effect of cSMM blendin
A novel approach to enhance rheological and filtration properties of water-based mud using polypropylene-silica nanocomposite
Deeper drilling depths and high pressure high temperature (HPHT) wells require good well planning at minimum cost and unproductive time. Polymer nanocomposite has emerged as a promising additive to enhance the thermal stability of conventional waterâbased muds (WBMs). In this study, polypropyleneâsilica nanocomposite (PPâSiO2 NC) was synthesized using hotâemulsion solâgel method. The performance of the PPâSiO2 NC in WBMs was critically examined and compared with that of partially hydrolyzed polyacrylamide (PHPA). Different characterization techniques were used to examine the morphology, structure information and thermal stability of the PPâSiO2 NC. The effect of 0.3 g, 0.6 g, 0.9 g, 1.2 g and 1.5 g each of PHPA and PPâSiO2 NC towards rheological properties, lubricity, filter cake thickness, and filtrate volume of WBM before and after thermal aging tests were studied. In addition, salt tolerance and cost analysis of the PPâSiO2 NC were evaluated. The results show that the PPâSiO2 NC has a spherical shape and a particle size distributed between 80 and 390 nm. The WBM with PPâSiO2 NC has better performance in controlling filtration and modifying rheological properties than the PHPA owing to the finely dispersed PPâSiO2 NC particles. With a concentration of 0.6 g after aging, the plastic viscosity of the PHPA mud decreased by 52.7% from 27.5 to 13 mPa s, while that of the PPâSiO2 NC mud reduced by 22.7% from 22 to 17 mPa s. Salt tolerance study showed that high concentration of potassium chloride affected the effectiveness of the PPâSiO2 NC in controlling HPHT filtrate volume. The cost analysis of the PPâSiO2 NC shows low cost of formulation. Hence, PPâSiO2 NC showed promising attributes for a good drilling mud
Effect of the surface charge of entrapped polypropylene at nanosilica composite on cuttings transport capacity of waterbased muds
Field experience has shown that inadequate cuttings transportation and hole cleaning results in wellbore drilling challenges, such as pipe sticking, high torque and drag, low rate of penetration, formation damage, etc. Designing a drilling mud with optimum rheological properties would be crucial to improve cuttings transportation efficiency. Several studies have shown that drilling muds that combine polymers with silica nanoparticles (SiO2 NPs) to form polymer nanocomposite (PNC) can effectively modify the rheology and enhance the filtration properties of water-based muds (WBMs). Studies on the significant decrease of the yield point that may lead to a huge reduction in the transport capacity of drilled cuttings using polypropylene-silica nanocomposite (PSNC) have not been reported. In this study, the effect of surface charge of newly developed PSNC on rheological and filtration characteristics of WBMs were examined. The results from zeta potential measurements showed that the newly developed PSNC and bentonite particles are both negatively charged at different levels of pH, which would lead to decrease in the yield point of the PSNC bearing mud samples. This problem was resolved using (3-aminopropyl) triethoxysilane (APTES) to modify the surface of the newly developed PSNC. From the experimental results, the amino-modified PSNC showed better performance in controlling filtration and modifying rheology than the unmodified PSNC due to the electrostatic attraction between bentonite and modified PSNC. The concentration of 1.5 g of the modified PSNC has a significantly higher yield point of 16.0 lb/100 ft2 than the unmodified PSNC with 6.4 lb/100 ft2 at 78 °F; demonstrating its capacity to provide better cuttings transportation than the unmodified PSNC. The surface functionalization of the newly developed PSNC in WBMs showed promising results in the rheology and filtration properties which demonstrates the viability of using them in drilling operations