Article
Chemistry, Physical
Xue Xia, Zhiqi Zhao, Wei Cai, Chuanxian Li, Fei Yang, Bo Yao, Guangyu Sun
Summary: The content of paraffin waxes affects the stability of W/O emulsions. Increasing the paraffin content improves emulsion stability but weakens the stability of asphaltene. Test temperature also has a significant impact on emulsion stability. Increasing the paraffin content at 30℃ benefits emulsion stability, while increasing the paraffin content at 15℃ helps to form a stronger wax crystal network structure and improve emulsion stability.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Energy & Fuels
Meiyi Qing, Jialei Liu, Qian Huang, Fankai Qin, Zhaohui Meng, Huaqing Liang, Zhongke Gao, Honglei Zhan, Xinyang Miao, Kun Zhao
Summary: In this study, oblique-incidence reflectivity difference (OIRD) analysis is demonstrated to be a powerful tool for the in situ analysis of wax precipitation. A detailed wax precipitation model is developed based on the hybrid detection of waxy oil and natural cooling. The advantages of the OIRD technique in distinguishing between different stages of the complex wax crystallization process are shown.
Article
Energy & Fuels
Oluwatoyin Olakunle Akinsete, Sunday Mathew Owoseni, Aliyu Adebayo Sulaimon
Summary: Wax deposition is a major challenge in the petroleum industry, and chemical wax control has been widely accepted. This study experimentally examined the inhibition effects of four chemical additives on waxy crude oils from the Niger Delta, and found that JTOX and JPAX significantly reduced the pour point, while WWD and WAT were effectively inhibited.
PETROLEUM SCIENCE AND TECHNOLOGY
(2023)
Article
Energy & Fuels
Sedi Helsper, Matthew W. Liberatore
Summary: Increasing oil production from cold environments has led to flow assurance issues caused by wax deposition and hydrate formation. This study investigates the high-pressure flow properties of waxy oils and finds that wax concentration has a larger effect on wax appearance temperature than pressure. Understanding waxy oil rheology under methane-saturated, high-pressure conditions is crucial for addressing flow assurance challenges in cold environments.
Article
Polymer Science
Marwa R. Elkatory, Mohamed A. Hassaan, Emad A. Soliman, Violeta-Carolina Niculescu, Maria Simona Raboaca, Ahmed El Nemr
Summary: One critical issue in the oil industry is the deposition of paraffin on pipelines during crude oil transportation and low-temperature restart processes. pour point depressants (PPDs) are effective processing aids to modify paraffin crystallization and improve the flow of waxy crude oil. In this study, the effect of pendants in comb-type copolymers on the flowability of crude oil in cold environments was investigated. The obtained PPDs, effective at a concentration of 2000 ppm, were able to decrease the pour point by up to 3 degrees Celsius. Rheometer analysis revealed the viscosity and yield stress of the petroleum waxy crude oil.
Article
Acoustics
Daechul Kim, Sungryul Shin, Wookeen Chung, Jong-Se Lim, Dong-Gun Lee, Dae-Mo Lee, Jiho Ha
Summary: The phenomenon of wax deposition in crude oil transportation pipelines can cause extensive damage. Therefore, it is essential to monitor flow assurance by estimating the wax appearance temperature (WAT) of the produced crude oil. This study proposes a method for determining WAT through ultrasonic characteristics analysis and confirms its high reliability through experiments.
Article
Energy & Fuels
Hongying Li, Chaohui Chen, Qian Huang, Yifei Ding, Yu Zhuang, Yiwei Xie, Miaomiao Xu, Shanpeng Han, Jinjun Zhang
Summary: Treatment with pour point depressant (PPD) can reduce the impedance changes caused by wax precipitation, making waxy crude oil easier to transport. Addition of PPD leads to increased capacitance and decreased resistance of wax particles, with a positive correlation between the viscosity reduction and the decrease in resistance. This study provides new insights into the functional mechanism of PPD in improving the flowability of waxy crude oil.
Article
Mechanics
Qian Huang, Hongying Li, Yiwei Xie, Yifei Ding, Yu Zhuang, Chaohui Chen, Shanpeng Han, Jinjun Zhang
Summary: It has been found in this study that applying an electric field to waxy crude oil gel can significantly weaken its structure, including reducing yield stress, moduli, and viscosity, and can transition from brittle-like to ductile-like fracture. A stronger structure weakening effect can be obtained at a higher field strength and lower temperature, and the effect induced by the electric field can be maintained for a certain period of time after removal.
JOURNAL OF RHEOLOGY
(2021)
Article
Energy & Fuels
Jia Liu, Jing Wang, Ti Dong, Deqing Liang
Summary: The formation of wax crystals and hydrates in deep-sea crude oil can affect the nucleation, growth, aggregation, and crystal structure of hydrates. Specifically, wax crystals inhibit hydrate formation, while hydrate formation reduces wax crystal aggregation, improving the flow characteristics of the hydrate slurry. Wax has no effect on the crystal structure of CH4 hydrate but impacts the distribution of the gas in cavities.
Article
Chemistry, Multidisciplinary
Jian Zhao, Xiangrui Xi, Hang Dong, Yuanhao Li, Minzheng Jiang
Summary: This study utilized a new in situ microscopic observation system and a self-created multi-angle composite light source to achieve the microscopic motions and structure dynamic transformation of wax crystals in the waxy crude oil subjected to shear for the first time. The research revealed that the aggregation between wax crystals plays an important role throughout the entire microstructure evolution, with two motion modes observed and three critical moments related to the microstructure evolution identified.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Energy & Fuels
Yuchuan Chen, Bohui Shi, Shunkang Fu, Qingping Li, Haiyuan Yao, Yang Liu, Xiaofang Lv, Junao Wang, Qingyun Liao, Xu Duan, Jing Gong
Summary: This study investigated the impact of wax crystals on hydrate formation and rheological properties of hydrate slurry through rheological experiments, revealing that both wax content and water cut affect the formation and growth of hydrates. Semi-empirical models were proposed to describe the inhibitory effect of wax crystals on hydrate nucleation kinetics. The study also found that the maximum values of hydrate slurry viscosity rate and calculated hydrate effective volume fraction decreased with increasing wax content, and hydrate growth time was extended with higher wax content.
Article
Mechanics
Sedi Helsper, Abdualbaset A. Ali, Matthew W. Liberatore
Summary: The study found that shear rate, cooling rate, and wax concentration affect the wax appearance temperature, with shear rate having a relatively small impact on WAT. Different fluid characteristics influence the change in yield stress upon wax formation. Adding shear rate to the phase diagrams of waxy oils could help address flow assurance needs in the industry.
Article
Physics, Applied
Kun Wang, Bo Peng, Runan Zhao, Hongmei Xu, Fei Yan
Summary: This study used molecular dynamics simulation to investigate the deposition process of heterogeneous waxy crude oil system on solid surfaces. The results showed that in a multiphase system, the morphology and density of paraffin wax crystals will change with temperature variation.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2021)
Article
Energy & Fuels
Yijie Wang, Qiyu Huang, Dongxu Zhang, Kun Wang, Xun Zhang, Yu Zhang, Zhenkang Xu, WenChen Liu
Summary: This study investigates the influence of asphaltenes on the evolution behavior of CO2 hydrates in waxy water-in-oil emulsions using a lab scale high-pressure stirring reactor. The results show that waxes inhibit CO2 hydrate nucleation, while the addition of asphaltenes enhances this inhibition effect. Moreover, asphaltenes facilitate the decomposition process of CO2 hydrates in waxy systems.
Article
Thermodynamics
Jia Liu, Decai Lin, Deqing Liang, Junhui Li, Zhiguang Song
Summary: Hydrates and waxes are major flow assurance issues in deep-water multi-phase transport units in the energy industry. This study investigates the anti-aggregation performance of an eco-friendly amphoteric surfactant, CAPB, in wax-containing oil-water systems. The concentration of CAPB and wax content synergistically influence its anti-aggregation performance. Adding 1.5 wt% CAPB effectively inhibits hydrate formation and improves flow in oil-water systems without wax. Adding 2.0 wt% CAPB slows hydrate growth rate and reduces inter-particle aggregation in waxy oil-water systems.
Correction
Nanoscience & Nanotechnology
Linxing Zhang, Qibin Li, Sen Tian, Guang Hong
JOURNAL OF NANOMATERIALS
(2020)
Article
Thermodynamics
Shukun Wang, Chao Liu, Qibin Li, Lang Liu, Erguang Huo, Cheng Zhang
APPLIED THERMAL ENGINEERING
(2020)
Article
Thermodynamics
Chuang Wu, Xiaoxiao Xu, Qibin Li, Xiaoxiao Li, Lang Liu, Chao Liu
Summary: The organic flash cycle is a efficient low-grade energy conversion technology, and by using an ammonia-water absorption refrigeration cycle, the proposed geothermal combined cooling and power (Geo-CCP) system can improve energy output efficiency. Among the eight considered organic fluids, n-Nonane is the most cost-effective and energy-efficient for the Geo-CCP system. Exergy analysis shows that the flasher and condenser-I have the highest exergy destructions in the system.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Engineering, Chemical
Guangping Lei, Qibin Li, Hantao Liu, Yayun Zhang
Summary: The study investigated the performance of multilayer Hex-star phosphorene in CO2 removal, discussing its behavior under different pressures, CO2 concentrations, and water content using molecular simulation and real adsorbed solution theory. The results demonstrated its excellent separation performance and potential as a promising material for natural gas purification.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Energy & Fuels
Yifan Gan, Qinglin Cheng, Shengli Chu, Zhihua Wang, Guohua Luan, Wei Sun, Shuang Wang, Chao Liu, Qibin Li, Yang Liu
Summary: The research established a molecular dynamics model to characterize the deposition and wall sticking behavior of waxy crude oil pipeline transportation, with the proposed equal density interpolation fitting method for determining wall contact angle. The study verified the model's accuracy and reliability by comparing simulation results to experimental data, and investigated the micro influence mechanism of surface free energy on adhesion behavior and the selective deposition process of waxy crude oil on the sedimentary layer.
Article
Energy & Fuels
Lu Zhang, Qibin Li, Chao Liu, Yang Liu, Shouyin Cai, Shukun Wang, Qinglin Cheng
Summary: Gas-water two-phase flow mechanism of CO2/CH4 in moist nanoporous media is studied in this research. Water molecules tend to form clusters to replace gas molecules at the surface and center region. An analytical theoretical slip model is established to quantify the effective viscosity and slip length of the binary mixtures system.
Article
Energy & Fuels
Qinglin Cheng, Yifan Gan, Zhihua Wang, Wei Sun, Shuang Wang, Chao Liu, Qibin Li, Yang Liu
Summary: The study found that waxy crude oil can settle on the inner tube, and its deposition and adhesion behavior change over time, leading to the gradual hardening of the sediment layer on the inner wall.
Article
Thermodynamics
Shukun Wang, Chao Liu, Shijie Zhang, Qibin Li, Erguang Huo
Summary: This paper proposes a double-layer multi-objective optimization framework for subcritical ORC systems in the geothermal field. Matching suitable fluids with specific geothermal temperatures is crucial for enhancing system performance and promoting marketability. Results show that the impacts of decision variables on system performance differ under different performance indicators.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Thermodynamics
Junrong Tang, Quanguo Zhang, Zhiping Zhang, Qibin Li, Chuang Wu, Xurong Wang
Summary: The study investigates the system performance enhancement of the sCO2 Brayton cycle with an absorption heat transformer (AHT), which serves as a bottoming cycle to upgrade waste heat energy. The sCO2/AHT system shows the best performance, with higher exergy efficiency and lower total product unit cost compared to the sCO2 system and sCO2/ORC system. Exergy analysis indicates effective reduction of energy loss and strengthened regeneration effect in the proposed system.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Thermodynamics
Lu Zhang, Chao Liu, Qibin Li, Shukun Wang, Shouyin Cai, Erguang Huo
Summary: This study investigates methane transport behavior through cylindrical and conical inorganic nanopores using density gradient-driven molecular dynamics, revealing the significant impact of aperture variation on methane permeability. Different flow behaviors of methane molecules are observed in nanopores with different shapes.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Physical
Yu Liu, Xiong Zheng, Qibin Li
Summary: A semi-empirical model was established to accurately calculate the heat capacity of hydrofluorocarbons and hydrofluoroolefins, with high regression accuracy and good extrapolation performance. Experimental results show that this model represents liquid heat capacity more accurately compared to other models.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Thermodynamics
Yu Liu, Chuang Wu, Xiong Zheng, Qibin Li
Summary: In this study, a thermal conductivity model was developed to represent the thermal conductivity of HFC/HFO/HCFO refrigerants in liquid phase. The proposed model is based on the combination of MET model and PR equation, with an empirical modification in the cross contribution term of MET model. The experimental results show that the proposed model is more accurate compared to conventional models.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2022)
Article
Biochemistry & Molecular Biology
Shuang Wang, Qinglin Cheng, Yifan Gan, Qibin Li, Chao Liu, Wei Sun
Summary: This paper investigates the microbehavior of wax aggregation in crude oil at low temperatures, focusing on the influence of different wax components and the shear effect exerted by pump and pipe wall in the process of crude oil pipeline transportation. Molecular dynamics models are established to simulate binary and multivariate systems of crude oil with different wax components. The findings reveal that longer wax molecular chains are more prone to aggregation and lower temperatures result in greater differences in wax molecular aggregation. The shear process affects the aggregation of wax molecules by destroying the stable structure of crude oil and inducing orientation and conformational transformation of wax molecules.
Article
Thermodynamics
Guanglin Jiang, Yu Liu, Qibin Li, Chao Liu
Summary: In this study, the thermal conductivity data of Octamethyltrisiloxane (MDM) and Hexamethyldisiloxane (MM) were measured using the transient hot wire method. A comparison between the present data and previously reported thermal conductivities was made, indicating good agreement. Additionally, a thermal conductivity model based on the modified Enskog theory was proposed. This study is of significance for the calculation and analysis of heat transfer in the organic Rankine cycle.
JOURNAL OF CHEMICAL THERMODYNAMICS
(2023)
Article
Chemistry, Physical
Rajalaxmi Sahoo, C. Reshma, D. S. Shankar Rao, C. V. Yelamaggad, S. Krishna Prasad
Summary: This study investigates the influence of the flexible spacer parity of a guest photoactive liquid crystalline dimer on the photonic bandgap features of the cholesteric and twist grain boundary smectic C phases of the host molecule. The results show that the parity of the photoactive dimer affects the width of the photonic bandgap and the blue-shift of the cholesteric phase. Additionally, the parity of the dimer also affects the layer spacing and two-dimensional periodicity of the liquid crystalline phases.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Sara Rozas, Alberto Gutierrez, Mert Atilhan, Alfredo Bol, Santiago Aparicio
Summary: This study presents a multiscale theoretical investigation on the use of bifunctional hydrophobic Deep Eutectic Solvent for carbon capture using tetrapropylammonium chloride, acetic acid, and ethanolamine. The characterization includes nanoscale analysis of CO2 absorption mechanisms and changes in liquid phase properties during gas capture.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Tabouli Eric Da-yang, Alhadji Malloum, Jean Jules Fifen, Mama Nsangou, Jeanet Conradie
Summary: In this study, the potential energy of different glycine tautomers and their interaction with Cu2+ cations was investigated. The results showed that the solvation medium and the presence of Cu2+ cations influenced the stability of glycine tautomers.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Xiaoliang Gou, Nan Ye, Qingqing Han, Junjie Cui, Long Yi Jin
Summary: In this study, amphiphilic rod-coil molecules with rigid DSA parts and flexible oligoether chains were designed and their assembly capacities were investigated. The morphology of the molecular aggregates was influenced by the pH of the solution and UV light, and the aggregates showed adsorption capacity for nitroaromatic compounds.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Shuang Liu, Liyan Shan, Cong Qi, Wenhui Zhang, Guannan Li, Bei Wang, Wei Wei
Summary: Optimizing the design of styrene-butadiene-styrene copolymer (SBS) is crucial for producing cost-effective SBS modifiers and improving road quality. This study examined the influence of SBS content and molecular structure on viscosity and compatibility. The results showed that the viscosity contribution of SBS is determined by its molecular structure and phase morphology.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Artem A. Petrov, Ekaterina A. Titova, Aydar A. Akhmadiyarov, Ilnaz T. Rakipov, Boris N. Solomonov
Summary: This work focuses on the thermochemistry of solvation of azeotropes. The enthalpies of dissolution of azeotropes in different mediums were determined, and the impact of the structure of the azeotropes on their properties in solution was discussed. A correlation between enthalpies of solvation and molar refraction was used to determine the vaporization enthalpies of azeotropes for the first time. The results were found to be consistent with literature data, obtained using direct and calculated methods. These findings contribute to the analysis of the structure-property relationships of azeotropes.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
L. V. Kamaeva, E. N. Tsiok, N. M. Chtchelkatchev
Summary: Understanding the correlations between liquids and solids allows us to predict the thermodynamic parameter range favorable for the formation of intriguing solid phases by studying liquids. In this study, we experimentally and theoretically investigated an Al-Cu-Co system within different composition ranges, and identified high-temperature solid phases. Our findings demonstrated the correlation between the boundaries of different solid phases and undercooling and viscosity in the concentration area.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
R. Aneesh Kumar, S. Jamelah Al-Otaibi, Y. Sheena Mary, Y. Shyma Mary, Nivedita Acharjee, Renjith Thomas, Renjith Raveendran Pillai, T. L. Leena
Summary: In this study, the interactions between doped and pristine coronenes and adenine nucleobases were investigated using Density Functional Theory. The optimal configurations, adsorption energies, charge transfer, and electrical properties of each complex were calculated. It was found that doped coronene had stronger adsorption strength and charge transfer compared to pristine coronene. The stability of the complexes was attributed to non-covalent interactions in the interactive region. The change in electrical conductivity of coronenes after adsorption suggested their sensitivity towards DNA bases. The predicted energy gap and prolonged recovery time for adenine-coronene configurations indicated the potential application of pristine/doped coronene in DNA detection.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Gang Zhou, Yongwei Liu, Biao Sun, Zengxin Liu, Cuicui Xu, Rulin Liu, Qi Zhang, Yongmei Wang
Summary: The CFD-DEM method was used to simulate the dust deposition pattern in the bronchus of anchor digging drivers, revealing the highest dust concentration in the vortex region of the working face. The study also found a positive correlation between dust particle diameter and bronchial deposition rate, and a negative correlation with alveolar deposition rate.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Yan Zhang, Yafei Luo, Lingkai Tang, Mingyan E, Jianping Hu
Summary: This study investigates the effects of different transition metal decorations on B12N12 nanocages on the adsorption properties of nitrosourea drugs using computational methods. The results reveal the presence of weak non-covalent interactions between metals and nanocages, and the interaction between drugs and nanocages plays a significant role in drug adsorption. Compared to free drugs, the adsorption of drugs on nanocages can facilitate electron transfer, reduce energy gaps and chemical hardness, indicating activity at the target site.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
C. I. Alcolado, J. Poblete, L. Garcia-Rio, E. Jimenez, F. J. Poblete
Summary: In this study, the selective oxidation of aromatic aldehydes was investigated using Ru(VI) as a catalyst and hexacyanoferrate (III) as a cooxidant in an alkaline medium. The reaction mechanism involves complex reaction orders for the oxidant and the aromatic aldehyde, while the reaction order for Ru(VI) is one. The proposed mechanism includes two catalytic cycles and the formation and decomposition of complexes. Quantitative structure-activity relationship analysis showed that deactivating groups in the para-position enhance the process.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Inez A. Barbieri, Marcos L. S. Oliveira, Franciele S. Bruckmann, Theodoro R. Salles, Leonardo Zancanaro, Luis F. O. Silva, Guilherme L. Dotto, Eder C. Lima, Mu. Naushad, Cristiano R. Bohn Rhoden
Summary: This study evaluated the adsorption of zolpidem on magnetic graphene oxide and synthesized magnetic graphene oxide adsorbents for zolpidem removal. The best magnetic nanoadsorbent was found to have a removal percentage of 87.07% at specific pH and temperature conditions. The results suggest that the removal of zolpidem is related to the surface chemistry of the adsorbent rather than the surface area of graphene oxide. The adsorbent showed excellent adsorption efficiency and magnetic behavior, making it a promising material for removing zolpidem from aqueous solutions.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Hongyan Huang, Chunquan Li, Siyuan Huang, Yuling Shang
Summary: This study examines the sensitivity of the thermal conductivity of water-based alumina nanofluids to changes in concentration, sphericity, and temperature. The results show that volume fraction and temperature have a significant impact on the thermal conductivity, while sphericity also needs to be considered. A support vector machine regression model was created to analyze the sensitivity of the thermal conductivity to different parameters. The findings indicate that temperature, sphericity, and volume fraction are the most sensitive variables.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Correction
Chemistry, Physical
V. M. Pergamenshchik, T. Bryk, A. Trokhymchuk
JOURNAL OF MOLECULAR LIQUIDS
(2024)
Article
Chemistry, Physical
Valentyn Rudenko, Anatolii Tolochko, Svitlana Bugaychuk, Dmytro Zhulai, Gertruda Klimusheva, Galina Yaremchuk, Tatyana Mirnaya, Yuriy Garbovskiy
Summary: This paper reports on the synthesis, structural characterization, spectral and nonlinear-optical properties of glass nanocomposites made of glass forming ionic liquid crystals and nanoparticles. The study reveals that by exciting the nanocomposites within their absorption band, a control over effective optical nonlinearities can be achieved, allowing the modification of the magnitude and sign of the effective nonlinear absorption coefficient. The proposed strategy using metal-alkanoates based glass-forming ionic liquid crystals and nanoparticles shows great potential for the development of nanophotonics and plasmonics technologies.
JOURNAL OF MOLECULAR LIQUIDS
(2024)
