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
PETROLEUM CHEMISTRY
·
2024
·Vol. 64
·期 2
·297-308
·
IF 1.3
Han Yating,Xia Xia,Peng Zexuan,Xiao Yang
Abstract To address the limitations of the existing catalytic hydrogenation and sulfuric acid sulfonation intended to remove aromatic hydrocarbons from liquid paraffin oils, the adsorption method was chosen for the adsorptive separation of phenanthrene, a typical aromatic hydrocarbon, from liquid paraffin oils. A zeolite imidazolate framework-8 (ZIF-8) precursor was firstly prepared, and then ZIF-8-derived porous carbon (ZDPC) adsorbents were obtained using different temperatures of carbonization of the precursor under nitrogen atmosphere; these adsorbents were then used for the adsorption and separation of phenanthrene from liquid paraffin oils. The experiment showed that the maximum specific surface area of a ZDPC adsorbent could reach 1458 m 2 /g at 900°C. However, the total pore volume and adsorption capacity of ZDPC porous carbon were maximal at the carbonization temperature of 800°C (1.59 cm 3 /g and 931 mg/g, respectively). The obtained results showed that an increase in the specific surface area of the adsorbent did not necessarily enhance the adsorption performance. However, compared with the specific surface area of the adsorbent, its adsorption performance is improved in the case of larger pore structures. Therefore, the pore structure of the adsorbent has a very important influence on the adsorption performance. The results of kinetic and thermodynamic studies showed that the pseudo-second-order model could better explain the adsorption process of ZDPC on phenanthrene, while the intra-particle diffusion model revealed that the adsorption mechanism represented a continuous three-stage process.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
·
2019
·
IF 2.886
Chenbo Ma,Jinjun Zhang,Kai Feng,Zixin Li,Chaohui Chen,Qian Huang,Yingda Lu
Electrical treatment is emerging as an efficient approach to improve the cold flowability of crude oils. In this work, waxy model oils under static state were electrically treated by an in-house apparatus. The influence of asphaltenes, the most aromatic of the heaviest components of crude oil, on the performance of electrical treatment was systematically examined for the first time. The presence of asphaltenes was found to significantly undermine the effectiveness of electrical treatment on waxy oils, and this negative influence became more pronounced at higher asphaltene contents. The effect of asphaltenes was largely independent on their aggregation state. Interestingly, although asphaltenes generally have a negative effect on electrical treatment of waxy oils, increasing polarity of asphaltenes alleviates this unfavorable effect. The results from microscopic analysis suggest that the less pronounced change in the size distribution of wax crystals might be one of the reasons for the unfavorable effects of asphaltenes on electrical treatment of waxy oils.
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
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2025
·
IF 1.9
Qianqian Lv,Chuanshuo Wang,Xiaoxuan Xu,Xiaofang Lv,Wen Xia,Jinru Shang,Aokai Qin,Qianli Ma,Yang Liu,Shidong Zhou,Jimiao Duan
Drag reducers have become a common method for reducing resistance and increasing transportation efficiency in pipeline transportation of waxy crude oil. The prominent heat transfer weakening effect of drag reducers may impact the deposition of waxy oil. This study uses cold finger experiments to clarify wax deposition characteristics and mechanisms in drag-reduced waxy oil. The wax deposition mass and components are examined under different temperatures, stirring rates, drag reducer dosages, and types. The results show that a low dosage of drag reducer at high stirring rates can simultaneously reduce the total wax deposition and the overall wax content in high waxy oil. 5 mg/kg drag reducer can reduce total wax deposition by up to 15.66% and overall wax content by 7.26%. A systematic investigation reveals that adding drag reducers changes the carbon number distribution in the wax deposition layer. This change is similar to the effect of increasing wall temperature. The heat insulation and transfer weakening effects of drag-reducing fluids are likely the main mechanisms inhibiting the increase in wax deposition mass and wax content. The heat insulation effect reduces the temperature gradient near the pipe wall, while the transfer weakening effect decreases radial heat transfer. However, under low stirring rates and high dosages, the deposition mass of the drag-reduced waxy oil system increases, with the adhesive effect of polymer-type drag reducers becoming more pronounced. These findings provide a foundation for optimizing drag reducer usage in waxy crude oil pipelines, potentially leading to significant energy savings and improved operational efficiency.
研究领域:
石油工程
·
化学工程
·
流体力学
·
传热学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2024
·
IF 6.5
Xiaodong Wang,Jun Shen,Yu Chen,Lin Li
The development of a multifunctional wood wax oil-based coating holds significant importance in meeting demands for wood protection and enhanced longevity of wood materials. Nevertheless, a simple method of developing such an integrated coating that possesses excellent durability, ultraviolet (UV) resistance, water resistance, and environmental friendliness remains a significant obstacle. In this paper, stearoyl chloride-grafted cellulose nanocrystals (SCNCs) with excellent compatibility with wood wax oil (WWO) coatings were prepared by combining cellulose nanocrystals (CNCs) with stearoyl chloride through a one-step non-homogeneous esterification reaction. Nanocomposite coatings were prepared by a simple one-step ultrasonic miscibility method using SCNCs as modified functionalized fillers. The prepared SCNC-WWO wood coatings had high hardness (grade H), strong adhesion (class 0, with no peeling), high abrasion resistance , good UV resistance, high hydrophobicity (water contact angle of 116°), and good water resistance (maintainable for 1 day). In addition, SCNCs with gas barrier properties can effectively inhibit the release of pollutants within the coatings, making this composite coatings environmentally friendly. Therefore, SCNC-WWO can be used as a high-performance coating for substantial protection of wood in harsh environments, and the strategy for developing it provides insight into the preparation of multifunctional wood paint.
研究领域:
材料科学
·
木材科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2020
·Vol. 306
·期 1
·2000509
·
IF 3.853
Bo Mu,Jianbing Cui,Baoping Yang,Jinfeng Cui,Junhong Guo,Li Tian
In this work, polyurethane (PU) materials containing paraffin oil are successfully prepared via an emulsion template method, which realizes the one-pot preparation of self-lubrication materials. The results show that the block copolymer surfactant (PEG 20 -PPG 70 -PEG 20 , P-123) can stabilize the nonaqueous PU emulsion with the paraffin oil serving both as dispersed phase of oil in oil emulsion and as a lubricant in the materials, and hence enables the fabrication of oil incorporating PU materials accordingly. Tribological tests show that the friction coefficient of PU material with 35% paraffin oil decreases to 0.05 which account for 93.06% reduce compared to that of pure PU.
研究领域:
材料科学
·
摩擦学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Jialin Dai,Jinjun Zhang,Chaohui Chen
In the present work, we employed model oil systems to examine the effects of resins upon the gelation and crystallization of waxy oils. Two types of waxes were explored, namely, n-tetracosane (wax A) and a commercial wax with a melting temperature of 52–54 °C (wax B). The resins were extracted from a deoiled asphalt from Venezuelan residue by the saturates, aromatics, resins, and asphaltenes fractionation method. The results from negative-ion electrospray ionization Fourier transform ion cyclotron resonance-mass spectrometry suggest that resins consist of one to four fused benzenes rings or one to two fused naphthalene rings constructed by N1, N1O1, N1S1, N1O1S1, N1O2, O1, O1S1, and O2 class species containing stacking aromatic rings. For both types of waxes examined, adding resins to the waxy oils suppresses wax precipitation and modifies the morphology of wax crystals, which collectively leads to lower gelation temperature and lower yield stress. Up to 7 °C of reduction in gelation temperature, 60% of reduction in yield stress, and 6 °C of reduction in wax appearance temperature were achieved when the waxy oils contain 7 wt % resins. Whereas for the wax A model oil, the gelation temperature decreases gradually with increasing resin content, for the wax B model oil, the resin effect is pronounced only at the resin concentration below 0.2 wt %. The reduction in yield stress caused by adding resins is also greater for the wax A model oil than wax B model oil. The different resin effects for the wax A model oil and wax B model oil might be caused by the compositional variations between wax A and wax B.
研究领域:
石油化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 6
·840
·
IF 4.034
Xianghua Zhang,Jiangtao Wang,Hongxiang Xu,Heng Tan,Xia Ye
This paper presents the facile synthesis of two different morphologies of WS2nanomaterials—WS2hexagonal nanoplates and nanoflowers—by a sulfurization reaction. The phases and morphology of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The tribological performance of the two kinds of WS2nanomaterials as additives in paraffin oil were measured using a UMT (Universal Mechanical Tester)-2 tribotester. The results demonstrated that the friction and wear performance of paraffin oil can be greatly improved with the addition of WS2nanomaterials, and that the morphology and content of WS2nanomaterials have a significant effect on the tribological properties of paraffin oil. The tribological performance of lubricating oil was best when the concentration of the WS2nanomaterial additive was 0.5 wt %. Moreover, the paraffin oil with added WS2nanoflowers exhibited better tribological properties than paraffin oil with added WS2hexagonal nanoplates. The superior tribological properties of WS2nanoflowers can be attributed to their special morphology, which contributes to the formation of a uniform tribo-film during the sliding process.
研究领域:
材料科学
·
摩擦学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2017
·
IF 2.843
Tao Li,Jun Xu,Run Zou,Hejian Jiang,Junyou Wang,Li Li,Martien A. Cohen Stuart,Robert K. Prud’homme,Xuhong Guo
Waxy crude oil containing large amounts of paraffins often results in various difficulties in extraction and transportation, especially at low temperature. Comb-type copolymers with phenyl pendants were found to be able to improve the flow ability of waxy oils effectively. To investigate the influence of spacer length between phenyl pendant and polymer backbone in comb copolymers on the flow ability of waxy oil, poly(α-octadecene-co-maleic acid phenyl alkyl amide)s with various spacer lengths were synthesized by modification of poly(α-octadecene-co-maleic anhydride) with aniline, phenethylamine, phentermine, and phenyl-undecanoicamide. Their effects on the morphology and crystallization of model and crude oils were observed by polarized light microscopy and DSC. The flow ability of both oils in the presence of copolymers was studied by means of rheology, including measuring yield stress, viscosity, and thixotropic properties. It is found that the spacer length remarkably affects the rheology and wax crystallization behaviors for both oils. The copolymer with a longer spacer can provide better flexibility of phenyl pendants to disperse asphaltenes more effectively, and the long spacer can cocrystallize with long-chain paraffins.
研究领域:
石油工程
·
高分子化学
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2024
·
IF 6
Mengjing Zhou,Bin Li,Aolin Wu,Zhigang Hu,Li Zhou,Hao Hu,Dandan Fu
In the preparation of bigels, wax is commonly used to create oleogels. However, oleogels made with wax typically have high melting points, which restrict their applicability and performance in practical applications. This study investigates the eutectic phase behavior of beeswax (BW) and rice bran wax (RBW) in bigels after ultrasonic treatment by varying their ratio. A bigel with a lower melting point was also prepared. The results indicated that eutectic phase behavior occurred between beeswax (BW) and rice bran wax (RBW) at a 6:4 ratio, reducing the gel's melting point to 53.4 °C. This was approximately 13.07 °C lower than that of wax mixtures with other ratios. X-ray diffraction (XRD) results showed that the β′-type crystal structure in the oleogels was often used in the food field. Fourier transform infrared spectroscopy (FTIR) analysis showed that the eutectic phase behavior enhanced the formation of intermolecular hydrogen bonds. Rheological analysis revealed that the bigel exhibited shear thinning behavior and gel network characteristics during the frequency sweep. Notably, the eutectic phase behavior significantly enhanced the gel strength and stability.
研究领域:
食品科学
·
材料科学
✓ 已验证
DOI
高影响因子
Petroleum Science
·
2024
·
IF 6
Yi-Hai Yang,Li-Na Zhang,Zheng-Nan Sun,Ming-Xing Bai,Guo-Lin Jing,Yang Liu,Xiao-Yan Liu
Modified ethylene-vinyl acetate copolymer (EVAM) and amino-functionalized nano-silica (NSiO 2 ) particles were employed as the base materials for the synthesis of the nanocomposite pour point depressant designated as EVAM-g-NSiO 2 . This synthesis involved a chemical grafting process within a solution system, followed by a structural characterization. Moreover, combining macro-rheological performance with microscopic structure observation, the influence of the nanocomposite pour point depressant on the rheological properties of the model waxy oil system was investigated. The results indicate that when the mass ratio of NSiO 2 to EVAM is 1:100, the prepared EVAM-g-NSiO 2 nanocomposite pour point depressant exhibits excellent pour point reduction and viscosity reduction properties. Moreover, the nanocomposite pour point depressant obtained through a chemical grafting reaction demonstrates structural stability (the bonding between the polymer and nanoparticles is stable). The pour points of model waxy oils doped with 500 mg/kg ethylene-vinyl acetate copolymer (EVA), EVAM, and EVAM/SiO 2 were reduced from 34°C to 23, 20, and 21°C, respectively. After adding the same dosage of EVAM-g-NSiO 2 nanocomposite pour point depressant, the pour point of the model wax oil decreased to 12 °C and the viscosity at 32 °C decreased from 2399 to 2396.9 mPa·s, achieving an impressive viscosity reduction rate of 99.9%. Its performance surpassed that of EVA, EVAM, and EVAM/SiO 2 . The EVAM-g-NSiO 2 dispersed in the oil phase acts as the crystallization nucleus for wax crystals, resulting in a dense structure of wax crystals. The compact wax crystal blocks are difficult to overlap with each other, preventing the formation of a three-dimensional network structure, thereby improving the low-temperature flowability of the model waxy oil.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 22
·21693-21700
·
IF 2.8
Luan Ling-Yu,Zhang Li,Wang Li-Hong
Synthesized organobentonite (SOB), montmorillonite (MMT), and commercial organobentonite (COB) were used as adsorbents for paraffin oil, a model pollutant in land-based oil spills and oil pipeline rupture. The characterization of clays was carried out with scanning electron microscopy (SEM), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). After adsorption, oil was separated from adsorbents with a carbon dioxide responsive solvent N,N-dimethylcyclohexylamine (DMCHA), and DMCHA was subsequently separated from paraffin oil upon CO 2 bubbling instead of distillation with high energy cost. The adsorption capacity of oil to SOB, MMT, and COB was 0.686, 1.124, and 1.239 g/g, respectively. It was found that the adsorption capacity and rinsed amount of the adsorbents depended on the d-spacing, which is related to surfactant content. Electrical conductivity and pH measurements suggested that the separation process occurred via two steps. Firstly, during the initial 35 min, carbonate ions coexisted with bicarbonate ions. Then, only bicarbonate ions existed after the introduction of CO 2 gas for 120 min. Thus, organobentonites were feasible for hydrocarbon adsorption and could be simply reused by an amine-based responsive solvent. This work provided a cost-effective and sustainable method of recycling of organobentonites and the responsive solvent, which can be used to deal with leaked oil and oil spills.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）