Promoting and Inhibitory Effects of Hydrophilic/Hydrophobic Modified Aluminum Oxide Nanoparticles on Carbon Dioxide Hydrate Formation

Hydrate-based CO2 capture from large emission sources is considered a promising process for greenhouse gas mitigation. The addition of nanoparticles may promote or inhibit the formation of hydrates. In this work, CO2 hydrate formation experiments were performed in a dual-cell high-pressure reactor. Non-modified, hydrophilic modified and hydrophobic modified aluminum oxide (Al2O3) nanoparticles at different concentrations were added to assess their promoting or inhibitory effects on CO2 hydrate formation. The equilibrium temperature and pressure, induction time, and total gas consumption during CO2 hydrate formation were measured. The results show that the presence of Al2O3 nanoparticles exerts little effect on the phase equilibrium of CO2 hydrates. Under the experimental conditions, the addition of all Al2O3 nanoparticles imposes an inhibitory effect on the final gas consumption except for the 0.01 wt% addition of hydrophilic modified Al2O3 nanoparticles. The induction time required for the nucleation of CO2 hydrates mainly ranges from 70 to 90 min in the presence of Al2O3 nanoparticles. Compared to the absence of nanoparticles, the addition of non-modified and hydrophilic modified Al2O3 nanoparticle reduces the induction time. However, the hydrophobic modified Al2O3 nanoparticles extend the induction time.

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The Effect of Experimental Conditions on Methane (95%)–Propane (5%) Hydrate Formation

Energies ◽

10.3390/en13246710 ◽

2020 ◽

Vol 13 (24) ◽

pp. 6710

Author(s):

Sotirios Nik. Longinos ◽

Mahmut Parlaktuna

Keyword(s):

Power Consumption ◽

Separation Factor ◽

Induction Time ◽

Hydrate Formation ◽

Equilibrium Line ◽

General View ◽

Experimental Conditions ◽

Rushton Turbine ◽

Pitched Blade Turbine

In the present study, the effect of different kinds of impellers with different baffles or no baffle was investigated. Up-pumping pitched blade turbine (PBTU) and Rushton turbine (RT) were the two types of impellers tested. The reactor was equipped with different designs of baffles: full, half and surface baffles or no baffles. Single (PBTU or RT) and dual (PBTU/PBTU or RT/RT) use of impellers with full (FB), half (HB), surface (SB) and no baffle (NB) combinations formed two sets of 16 experiments. There was estimation of rate of hydrate formation, induction time, hydrate productivity, overall power consumption, split fraction and separation factor. In both single and dual impellers, the results showed that RT experiments are better compared to PBTU in rate of hydrate formation. The induction time is almost the same since we are deep in the equilibrium line while hydrate productivity values are higher in PBTU compared to RT experiments. As general view RT experiments consume more energy compared to PBTU experiments.

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Effect of Aluminum Oxide Nanoparticles Films Thickness on Optical Properties

International Journal of Scientific Research and Management ◽

10.18535/ijsrm/v6i11.ec02 ◽

2018 ◽

Vol 6 (11) ◽

Author(s):

I.H. Hilal ◽

H. l. Abdullah ◽

A. M. Ibraheem

Keyword(s):

Thin Films ◽

Optical Properties ◽

Aluminum Oxide ◽

Band Gap Energy ◽

Al2o3 Nanoparticles ◽

Structural And Optical Properties ◽

Aluminum Oxide Nanoparticles ◽

Force Microscopy ◽

Atomic Force ◽

Different Thickness

The aluminum oxide (Al2O3) nanoparticles thin films has been prepared via UV-irradiation methods using metal salts (aluminum nitrate Al(NO3)3) with different thickness (150 , 200, 300 , and 400) and measuring structural and optical properties. The structure of the (Al2O3) nanoparticles thin films was tested with X-Ray showed that have six main diffraction features corresponding to (111), (311), (222), (400), (511) and (440) planes . The results of atomic force microscopy ( AFM ) indicated that all films have grain size about 25.97-65nm . The optical band gap energy was decreased by the increase of thickness from (5.19-4.68) eV then used aluminum oxide as gas sensor.

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The Effects of Using Aluminum Oxide Nanoparticles as Heat Transfer Fillers on Morphology and Thermal Performances of Form-Stable Phase Change Fibrous Membranes Based on Capric–Palmitic–Stearic Acid Ternary Eutectic/Polyacrylonitrile Composite

Materials ◽

10.3390/ma11091785 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1785 ◽

Cited By ~ 3

Author(s):

Huizhen Ke ◽

Yonggui Li

Keyword(s):

Heat Transfer ◽

Aluminum Oxide ◽

Stearic Acid ◽

Phase Change ◽

Ternary Eutectic ◽

Stable Phase ◽

Al2o3 Nanoparticles ◽

Aluminum Oxide Nanoparticles ◽

Scanning Calorimetry ◽

Fibrous Membranes

In this paper, innovative capric–palmitic–stearic acid ternary eutectic/polyacrylonitrile/aluminum oxide (CA–PA–SA/PAN/Al2O3) form-stable phase change composite fibrous membranes (PCCFMs) with different mass ratios of Al2O3 nanoparticles were prepared for thermal energy storage. The influences of Al2O3 nanoparticles on morphology and thermal performances of the form-stable PCCFMs were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and measurement of melting and freezing times, respectively. The results showed that there was no apparent leakage trace from the SEM observation. The DSC analysis indicated that the addition of Al2O3 nanoparticles had no significant effect on phase transition temperatures and enthalpies of the CA–PA–SA/PAN/Al2O3 form-stable PCCFMs. The melting peak temperatures and melting enthalpies of form-stable PCCFMs were about 25 °C and 131–139 kJ/kg, respectively. The melting and freezing times of the CA–PA–SA/PAN/Al2O310 form-stable PCCFMs were shortened by approximately 21% and 23%, respectively, compared with those of the CA–PA–SA/PAN form-stable PCCFMs due to the addition of Al2O3 nanoparticles acting as heat transfer fillers.

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Computation in the Analysis of Techno-Economic of the Production of Al2O3 (Aluminum Oxide) Nanoparticles through Precipitation Method

International Journal of Informatics, Information System and Computer Engineering (INJIISCOM) ◽

10.34010/injiiscom.v2i1.5415 ◽

2021 ◽

Vol 2 (1) ◽

pp. 65-76

Author(s):

Yusrianti Sabrina Kurniadianti ◽

◽

Adzra Zahra Ziva ◽

Yuni Kartika Suryana ◽

Risti Ragadhita ◽

...

Keyword(s):

Economic Evaluation ◽

Aluminum Oxide ◽

Net Present Value ◽

Raw Material ◽

Industrial Scale ◽

Precipitation Method ◽

Al2o3 Nanoparticles ◽

Present Value ◽

Aluminum Oxide Nanoparticles ◽

Evaluation Parameters

This study aims to demonstrate computation in the techno-economic analysis of the production of aluminum oxide (Al2O3) using the precipitation method on an industrial scale. This evaluation is based on the perspective of technical and economic evaluation. Several economic evaluation parameters were analyzed to obtain potential information from the manufacture of Al2O3 nanoparticles based on gross profit margin, payback period, and cumulative net present value. The results of this study identified that the manufacture of Al2O3 nanoparticles using the precipitation method could be done industrially. Based on the engineering perspective, Al2O3 nanoparticles can be produced as much as 6.9 tons and earn an annual profit of 144,635.69 USD with a period of 20 years. To ensure that this project can be carried out, an economic evaluation is made based on estimates of ideal and non-ideal conditions, including tax increases, sales changes, raw material prices, utility prices, and labor’s salary. This study is expected to provide information for the manufacture of Al2O3 nanoparticles using the precipitation method on an industrial scale.

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Influence of THF and THF/SDS on the Kinetics of CO2 Hydrate Formation Under Stirring

Frontiers in Energy Research ◽

10.3389/fenrg.2021.633929 ◽

2021 ◽

Vol 9 ◽

Author(s):

Hongliang Wang ◽

Qiang Wu ◽

Baoyong Zhang

Keyword(s):

Induction Time ◽

Pure Water ◽

Formation Rate ◽

Sodium Dodecyl ◽

Hydrate Formation ◽

Gas Absorption ◽

Obvious Effect ◽

Gas Uptake ◽

Gas Consumption ◽

And Control

Hydrate-based gas separation is a potential technology for CO2 recovery and storage, and its products can be used for fire prevention and control in mines. Promoters are often employed to accelerate or moderate hydrate formation. In this study, experiments were performed to examine the effects of different concentrations of the thermodynamic promoter tetrahydrofuran (THF) and kinetic promoter sodium dodecyl sulphate (SDS) on CO2 hydrate formation under stirring. The results showed that THF significantly shortens the induction time of CO2 hydrates; however, because THF occupies a large cavity in the hydrate structure, it also reduces the gas absorption and hydrate formation rate. SDS has no obvious effect on the induction time of hydrates, but it can increase the gas storage density and hydrate formation rate. Using THF and SDS together consumed more CO2 than using THF alone or pure water. The peak gas consumption rate was 2.3 times that of the THF system. The hydrate formation efficiency was improved by including both THF and SDS, which maximized both the hydrate formation rate and total gas uptake.

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РЕГУЛЮВАННЯ СТІЙКОСТІ РІДКИХ МІКРОСТРУМЕНІВ ПОЛІПРОПІЛЕНУ В МАТРИЦІ СПІВПОЛІАМІДУ ЗА РАХУНОК НАНОДОБАВОК

Technologies and Engineering ◽

10.30857/2786-5371.2021.2.6 ◽

2021 ◽

pp. 60-69

Author(s):

NATALIA REZANOVA ◽

YURII BUDASH ◽

VIKTORIIA PLAVAN ◽

ALLA KORSHUN ◽

SERHII PRYSTYNSKYI

Keyword(s):

Aluminum Oxide ◽

Cross Sections ◽

Capillary Waves ◽

Al2o3 Nanoparticles ◽

Aluminum Oxide Nanoparticles ◽

Degree Of Dispersion ◽

The Matrix ◽

Liquid Microjets ◽

Kinetics Of ◽

Instability Coefficient

Goal. Investigation of the effect of the concentration of nanoparticles of aluminum oxide (Al2O3) and alumina modified with silver (Ag/Al2O3) on the decomposition kinetics of liquid microjets of polypropylene (PP) in a copolyamide (CPA) matrix and the possibility of controlling the microfibrillar morphology of the PP/CPA blend.Methodology. The components of the blend were mixed on a screw-disk extruder. The kinetics of the disintegration of liquid microjets was studied using a technique based on the theory of destabilization of a liquid cylinder under the action of capillary waves. The degree of dispersion of polypropylene in the matrix was evaluated by photomicrographs of cross sections of the extrudates of the blends.Results. Nanoadditives of the original and silver-modified aluminum oxide with a content of (0.1 ÷ 3.0) wt.% In the blend increase the compatibility of the components: the surface tension (γαβ) in the compositions of all compositions decreases. Ag/Al2O3 nanoparticles are more effective than aluminum oxide nanoparticles - the γαβ value decreases by 9.6 and 5.3 times, respectively, which ensures a high degree of dispersion of the dispersed phase component in the matrix. The disintegration resistance of polypropylene microjets is increasing, as evidenced by a decrease in the instability coefficient (q) and an increase in the microjet lifetime (tl). The curves of q and tl dependence on the additive content have an extreme character. The minimum values of the instability coefficient of microjets and the maximum values of their lifetime are achieved at a nanoparticle concentration corresponding to the lowest interfacial tension.Scientific novelty. The positive effect of the investigated nanoadditives on the kinetics of the decomposition of liquid microjets of polypropylene in the copolyamide matrix has been established. The highest modifying effect in the presence of Ag/Al2O3 nanoparticles is due to their amphiphilic nature, which ensures the predominant localization of nanoparticles at the interface and a synergistic increase in the degree of compatibility in the PP/CPA system.Practical significance. The regularities of increasing the stability of liquid microjets to disintegration in polymer blends filled with nanoparticles have been established, which will make it possible to determine the parameters of the processes of mixing and forming fibers and films, in which the microfibrillar structure arising during the flow of the melt will remain unchanged in the products.

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Insights into kinetic inhibition effects of MEG, PVP, and L-tyrosine aqueous solutions on natural gas hydrate formation

Petroleum Science ◽

10.1007/s12182-020-00515-0 ◽

2020 ◽

Author(s):

Amir Saberi ◽

Abdolmohammad Alamdari ◽

Ali Rasoolzadeh ◽

Amir H. Mohammadi

Keyword(s):

Natural Gas ◽

Aqueous Solutions ◽

Gas Hydrate ◽

Induction Time ◽

Hydrate Formation ◽

View Point ◽

Natural Gas Hydrate ◽

Time Data ◽

Gas Hydrate Formation ◽

Gas Consumption

Abstract It is necessary to understand all the prerequisites, which result in gas hydrate formation for safe design and control of a variety of processes in petroleum industry. Thermodynamic hydrate inhibitors (THIs) are normally used to preclude gas hydrate formation by shifting hydrate stability region to lower temperatures and higher pressures. Sometimes, it is difficult to avoid hydrate formation and hydrates will form anyway. In this situation, kinetic hydrate inhibitors (KHIs) can be used to postpone formation of gas hydrates by retarding hydrate nucleation and growth rate. In this study, two kinetic parameters including natural gas hydrate formation induction time and the rate of gas consumption were experimentally investigated in the presence of monoethylene glycol (MEG), L-tyrosine, and polyvinylpyrrolidone (PVP) at various concentrations in aqueous solutions. Since hydrate formation is a stochastic phenomenon, the repeatability of each kinetic parameter was evaluated several times and the average values for the hydrate formation induction times and the rates of gas consumption are reported. The results indicate that from the view point of hydrate formation induction time, 2 wt% PVP and 20 wt% MEG aqueous solutions have the highest values and are the best choices. It is also interpreted from the results that from the view point of the rate of gas consumption, 20 wt% MEG aqueous solution yields the lowest value and is the best choice. Finally, it is concluded that the combination of PVP and MEG in an aqueous solution has a simultaneous synergistic impact on natural gas hydrate formation induction time and the rate of gas consumption. Furthermore, a semi-empirical model based on chemical kinetic theory is applied to evaluate the hydrate formation induction time data. A good agreement between the experimental and calculated hydrate formation induction time data is observed.

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Kinetic effect of single MgCl2 and NaCl aqueous solutions on ethane hydrate formation

Canadian Journal of Chemistry ◽

10.1139/cjc-2014-0535 ◽

2015 ◽

Vol 93 (8) ◽

pp. 891-896 ◽

Cited By ~ 3

Author(s):

Zhen Long ◽

Deqing Liang ◽

Dongliang Li

Keyword(s):

Growth Rate ◽

Induction Time ◽

Storage Capacity ◽

Pure Water ◽

Hydrate Formation ◽

Initial Pressure ◽

Solution Concentration ◽

Diffusion Reaction ◽

Gas Consumption ◽

And Storage

Experimental data on the kinetics of C2H6 hydrate formation in the presence of pure water and two aqueous single solutions, MgCl2 and NaCl, are presented in this study. The measurements of experimental hydrate formation process were performed in a high pressure reactor at 276.15 K, at initial pressure range of 2.0–2.4 MPa, and solution concentration range of 2.34–10 wt%. The effect of solution concentration and initial pressure on the induction time, gas consumption, conversion, and storage capacity and growth rate was examined. It was observed that with the increase of the solution concentration, the induction time increased, while the storage capacity and the number of moles of C2H6 consumed decreased. A diffusion-reaction kinetics model was employed to predict the hydrate growth rate at the beginning of hydrate formation. The results showed that the addition of MgCl2 and NaCl decreased the apparent rate constant, and MgCl2 had a greater effect than NaCl in inhibiting the hydrate growth.

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