ENERGY & FUELS
·
2019
·
IF 3.021
Yuchuan Chen,Bohui Shi,Yang Liu,Qianli Ma,Shangfei Song,Lin Ding,Xiaofang Lv,Haihao Wu,Wei Wang,Haiyuan Yao,Jing Gong
With the tendency of the offshore petroleum industry moving to the deep-water fields, there are several challenges for the exploration and development of oil and gas with higher paraffin content in the deep-water severe environment, especially the complex flow assurance issues including the coexistence of wax precipitation and hydrate formation. The effects of wax on hydrate slurry viscosity, hydrate nucleation and growth, and hydrate dissociation were investigated in a rheometer. Results indicated that the stage characteristics of viscosity evolution during hydrate formation in waxy and wax-free emulsions were different, and two stages could be observed during the hydrate growth process in the presence of wax. Hydrate slurry viscosity increased with the wax content. The coupled hydrate–wax aggregates were difficult to be broken by the constant shearing force. The shear-thinning property of the hydrate slurry was not affected by the precipitated wax. Hydrate formation was inhibited due to the wax precipitated in the oil phase. Specifically, cyclopentane hydrate critical time and growth time increased with the wax content. The calculated hydrate volume fraction decreased with the wax content based on the suspension viscosity model. It was difficult for a water bridge to form between two hydrate particles during the hydrate-dissociation process with 3.0 and 5.0 wt % wax contents; therefore, no obvious increase in the slurry viscosity was observed when the slurry viscosity decreased during the dissociation process.
研究领域:
石油工程
·
流变学
·
能源材料
·
多相流
·
流动保障
✓ 已验证
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Yang Liu,Chengxuan Wu,Xiaofang Lv,Hui Du,Qianli Ma,Chuanshuo Wang,Shidong Zhou,Bohui Shi,Shangfei Song,Jing Gong,Jimiao Duan
During deep-sea and ultra-deep-sea oil and gas exploitation, multiphase transmission lines are prone to be clogged by sediments produced by the various components in crude oils under extreme subsea conditions, such as hydrates, wax, resins, and asphaltenes. The pipelines face higher plugging risks when these deposits exist simultaneously. In order to elucidate the effects of wax and anti-agglomerants (AA) on hydrate growth and aggregation, microscopic morphology observation and cohesive force measurement of cyclopentane hydrate particles were conducted through a piece of equipment similar to the micromechanical force (MMF) apparatus. Results showed that in the low concentration of AA (0.05 wt%), hydrate particles experienced an approximately 10 % reduction in the profile area after converting water droplets to hydrate particles. Furthermore, the cohesive force between hydrate particles decreased from 8.57 ± 0.90 mN/m to 3.51 ± 0.43 mN/m as the AA concentration increased from 0.05 to 0.2 wt%. On the other hand, the presence of wax significantly altered the morphologies of hydrate particles. When wax coexisted with AA, the hydrate cohesive force was reduced by wax under low AA concentration (0.05 wt%) but increased under higher AA concentration. For a given concentration of AA, the hydrate cohesive force increased with the increasing wax content (from 0.1 to 0.3 wt%), indicating that wax crystals weakened the efficiency of AA, such as Span 80. Additionally, the effect of surface wetness of waxy hydrate particles on their cohesion was also investigated. The liquid bridge appeared between wet waxy hydrate particles, while the solid–solid contact existed between dry waxy hydrate particles. The cohesive force between dry waxy hydrate particles was smaller. Either liquid bridge or solid–solid contact that dominated hydrate cohesive force was affected by wax.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2022
·Vol. 9
·期 18
·2200160
·
IF 6.389
Xiaoqing Hao,Zhengrong Sun,Shuwang Wu,Ta-Wei Wang,Yubo Liu,Yang Wu,Ximin He,Qinze Liu,Feng Zhou
Polydimethylsiloxane (PDMS) is one of the most popular materials to protect infrastructures from the complicated environment due to its chemical stability, nontoxicity, low cost, high durability, and chain flexibility. Herein, a series of organic–inorganic hybrid coatings are prepared by simply grafting loop-like PDMS on a solid surface. Owning to the low surface energy and high mobility of PDMS chains, the special characteristics, including liquid repellency, anti-fouling, self-lubrication, anti- and delay-ice, anti-paraffin, etc., are presented. To confirm the liquid-like slippery nature of PDMS surface, the controlled de-icing and de-waxing tests on rigid chain surfaces are conducted. The liquid-like nature of PDMS allows ice or paraffin to have a low adhesion in a slip state, but a fractured state on alkylated and perfluorinated surface with a high adhesion strength. In addition, the flexible PDMS chains grafted on the inorganic silica layer by stable covalent bond endow the surface with excellent durability, including maintaining low ice adhesion during 50 icing-deicing cycles, resistance to UV irradiation, washing or soaking in organic solvent, etc. This work provides a simple approach for constructing self-lubricative low surface energy coating to realize de-ice and de-wax easily, which may have a broad prospect of application in equipment protection.
研究领域:
材料科学
·
表面工程
·
涂层技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Changjian Li,Kexin Chi,Hang Yu,Yahui Guo,Weirong Ya,He Qian
Dissipation of an organophosphorus pesticide, trichlorfon, in natural and waxed apples during storage was studied. The results showed that the trichlorfon content in natural and waxed apples decreased by 85% and 64%, respectively, during storage. The morphology of the surface film was dense and regular, which resulted in a higher water vapor resistance and a lower respiration rate in the waxed apples. This indicates that waxing affected the dissipation of pesticide residues in the apple storage environment, increasing food safety risk. Ozone was used to remove the residual pesticides on the apple surface. The trichlorfon degradation rate reached 73%. The ozone treatment had no effect on the surface color of the apple, which means that the fruit can be pre-treated with ozone prior to waxing or storage.
研究领域:
食品安全
·
植物保护
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Yingying Cao,Yongqiang Zhang,Ying Zhang,Ling Wang,Lunchao Lv,Xifei Ma,Shaojuan Zeng,Hui Wang
Artemisinin is mainly derived from Artemisia annua L. Since the leaves composition is complex, artemisinin purification faces great challenges. In this work, functional chitosan membranes were fabricated by a one-step hydrolysis method through grafting long-chain alkyl group on the surface of chitosan to increase its hydrophobicity. The as-prepared membranes were used to adsorb wax oil ( i.e. , the impurity components) in Artemisia annua L. and to avoid co-precipitation of wax oil along with artemisinin using the crystallization technique for purification. Octyl-trimethoxysilane modified chitosan membrane (FCM-C 8 ) showed excellent capability to intensify this purification process. The product purity could reach more than 98 % using one crystallization step under the optimal conditions, and in this case, adsorption capacity of FCM-C 8 for wax oil was 478.9 mg/g. In addition, the adsorption kinetics and mechanism of wax oil on FCM-C 8 were studied. The membrane can simultaneously adsorb multiple components in wax oil through interactions like electrostatic forces, hydrogen bondings.
研究领域:
生物工程
·
制药工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2022
·Vol. 14
·期 9
·1786
·
IF 4.967
Dongyang Liu,Yuqing Duan,Shumei Wang,Murong Gong,Hongqi Dai
Studies have shown that fluorinated oil repellents are potentially harmful to humans and the environment, and therefore, the development of non-toxic, green, and environmentally friendly oil repellents has become inevitable. Microcrystalline wax is a branched saturated alkane with a molecular weight of 580–700 Da, which has a lower surface tension than edible oil. Herein, microcrystalline wax emulsion (fluorine-free oil repellent) was prepared by mechanical stirring–homogenization, the effects of emulsifier ratio and dosage on the emulsion performance were systematically investigated, and the resultant stable microcrystalline wax emulsions were applied to the paper surface to explore the oil and water resistance and water vapor barrier performance. The results showed that stabilized microcrystalline wax emulsion was obtained at the emulsifier Span-80/Tween-80 ratio of 5:5, and the emulsifier dosage was 20% (relative to the microcrystalline wax). When 6 g/m2of microcrystalline wax was applied to the surface of starch pretreated paper, the kit rating value of the paper was high, at up to 10/12, the Cobb60value decreased to 12.5 g/m2, the overall migration of paper was less than 10 mg/dm2, and the water vapor permeability was reduced by 81.9%, which met the requirements of oil and water resistance performance of food packaging paper.Keywords:microcrystalline wax emulsion;oil and water resistance;fluorine-free oil repellent
研究领域:
食品科学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Zeheng Peng,Wei Wang,Lin Cheng,Weijie Yu,Kai Li,Yingming Liu,Mengxin Wang,Fan Xiao,Huirong Huang,Yang Liu,Qianli Ma,Bohui Shi,Jing Gong
In this paper, the effect of the ethylene vinyl acetate (EVA) copolymer, commonly used in improving rheological behavior of waxy oil, is introduced to investigate its effect on the formation of cyclopentane hydrate in a water-in-waxy oil emulsion system. The wax content studied shows a negative effect on the formation of hydrate by elongating its induction time. Besides, the EVA copolymer is found to elongate the induction time of cyclopentane hydrate through the cocrystallization effect with wax molecules adjacent to the oil–water interface.
研究领域:
化学工程
·
材料科学
·
石油工程
✓ 已验证
DOI
高影响因子
Food & Function
·
2020
·Vol. 11
·期 9
·7727-7735
·
IF 4.171
Yuan Gao,Shimin Wu
A novel oleogel system was developed, and its characteristics and properties were investigated. The results indicate that a low-cost, low-fat and low hardness oleogel product was formed by potato starch, candelilla wax, oil, and distilled water. Specifically, the content of potato starch and candelilla wax in the oleogel system was 5 wt%. A potato starch/candelilla wax ratio from 1.22 to 5.67 led to the formation of a type II starch-lipid oleogel system, and the content of distilled water was 45 times the starch content. All the above-mentioned information demonstrated that starch/wax-based oleogels are a typical lipid system. They can reduce the content of wax and oil in oleogel systems, form oleogel products with low hardness values and exhibit great potential in the field of low-fat food and low-cost food industrial applications.
研究领域:
食品科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Shikun Tong,Kele Yan,Jianbo Zhang,Zhiyuan Wang
Hydrate and wax phase transitions are typical flow risks during oil and gas development. The wax on hydrate formation was systematically studied based on dual-scale experimental platform. The sensitivity analysis on hydrate growth illustrates that the wax inhibits hydrate growth and the maximum reduction of hydrate growth rate is 79.6 % in waxy emulsions, and the wax on hydrate conversion ratio decreased the most by 27.2 %. The promoting effect of water content, subcooling, and stirring rate on hydrate growth increased by more than 10 times, 2 times, and 7 times, respectively. The droplet size first decreases and then increases as the wax concentration increases in emulsions. The mechanism of hydrate growth in waxy emulsions considers bidirectional growth and pores renewal of hydrate particles, and the mean error of the prediction model is 8.4 %. This work provides data basis and theoretical foundation for flow assurance management in oil and gas filed.
研究领域:
石油工程
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 133
·期 42
·
IF 1.866
Yu Zhang,Jia Song,Hongling Chen
The purpose of the present work was to develop a fragrance encapsulation system using polyacrylate/paraffin microcapsules. The Polyacrylate/paraffin microcapsules were fabricated by the method of suspension polymerization in Pickering emulsion. Morphology, size distribution, and thermal resistance of polyacrylate/paraffin microcapsules were investigated by scanning electron microscopy, light scattering particle size analyzer, and thermogravimetric analyzer. Results indicated that the crosslinked PMMA/paraffin microcapsules and P(MMA-co-BMA)/paraffin microcapsules prepared under optimal conditions presented regular spherical shape and similar size distribution. The crosslinked P(MMA-co-BMA)/paraffin microcapsules exhibited better thermal stability, with a thermal resistance temperature up to 184 °C. Fragrance microcapsules were prepared by encapsulating fragrance into crosslinked P(MMA-co-BMA)/paraffin microcapsules. The prolonged release performance of fragrance microcapsules was measured by ultraviolet-visible near-infrared spectrophotometer. 63.9% fragrance was retained after exposing fragrance microcapsules in air for 3 months, and the fragrance continued to release over 96 h in surfactant solution (sodium lauryl sulfonate, 20 wt %). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 44136.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2022
·
IF 4.654
Yijie Wang,Qiyu Huang,Dongxu Zhang,Kun Wang,Xun Zhang,Yu Zhang,Zhenkang Xu,WenChen Liu
The formation of hydrate increases the uncertainty of the flow system in subsea multiphase transportation pipelines. Waxes and asphaltenes have been found to influence hydrate formation, but the detailed mechanism of their interaction remains unclear. A lab-scale high-pressure stirring reactor was used to analyze the influence of asphaltenes on CO2 hydrate evolution behavior in waxy water-in-oil (W/O) emulsions. Results demonstrated that waxes inhibited CO2 hydrate nucleation. The addition of asphaltenes promoted the inhibition effect of waxes, and the enhancement effect was nonmonotonic with the asphaltene contents increased. Based on microscopic observation and wax precipitation characteristics, this behavior could be interpreted as the competitive effect of increased adsorption of wax crystals on the surface of the droplets and reduced amount of wax precipitation. Moreover, asphaltenes were found to facilitate the decomposition process of CO2 hydrates in waxy systems by decreasing the wax precipitation amount and stabilizing the emulsion. This work can provide potential engineering guidance for flow assurance applications.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Haoran Zhu,Chuanxian Li,Zongming Xiu,Zhiqiang Zhao,Kai Mu,Hui Dai,Feng Wang,Fei Yang,Bo Yao
In this paper, a novel ethylene-vinyl acetate copolymer (EVA)/amino-functionalized polymethylsilsesquioxane (PAMSQ) composite wax inhibitor (WI) was prepared through melt blending, and the rheological and wax depositing properties of the doped crude oil were studied. The EVA/PAMSQ composite can strongly crystallize with wax molecules and trigger the formation of compact wax flocs, which greatly improve the rheological properties of crude: compared to the pure EVA at the same dosage, the composite can further decrease the gel point and apparent viscosity (25 °C) by 14.6 °C and 92.0%, respectively. The wax deposition can also be inhibited by adding the composite: adding EVA inhibits the mass of the wax deposit at 24 h by 62.3%, and this number is suppressed by 77.9% after adding the EVA/PAMSQ composite, but the wax molecule diffusion is accelerated and the wax content in the wax deposit rises because of the improved crude oil rheological characteristics. Here, we develop the gel structure theory to consider the wax deposition process affected by the WI. Adding the WI contributes little to the wax precipitation temperature but decreases the gel structural strength of the oil a lot, and thus, the oil near the pipe wall can only form the wax deposit with a higher wax content to resist the pipe wall shearing. Therefore, the crude oil added EVA/PAMSQ composite possesses not only the lowest wax deposit rate and the highest aging rate but also the highest wax content in the wax deposit.
研究领域:
材料科学
·
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）