Petroleum Science
·
2023
·
IF 5.6
Xi-Dao Wu,Peng Xiao,Bei Liu,Guang-Jin Chen,Jian-Hua Pang
CO 2 emulsions used for EOR have received a lot of interest because of its good performance on CO 2 mobility reduction. However, most of them have been focusing on the high quality CO 2 emulsion (high CO 2 fraction), while CO 2 emulsion with high water cut has been rarely researched. In this paper, we carried out a comprehensive experimental study of using high water cut CO 2 /H 2 O emulsion for enhancing oil recovery. Firstly, a nonionic surfactant, alkyl glycosides (APG), was selected to stabilize CO 2 /H 2 O emulsion, and the corresponding morphology and stability were evaluated with a transparent PVT cell. Subsequently, plugging capacity and apparent viscosity of CO 2 /H 2 O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube. Furthermore, a high water cut (40 vol%) CO 2 /H 2 O emulsion was selected for flooding experiments in a long sand pack and a core sample, and the oil recovery, the rate of oil recovery, and the pressure gradients were analyzed. The results indicated that APG had a good performance on emulsifying and stabilizing CO 2 emulsion. An inversion from H 2 O/CO 2 emulsion to CO 2 /H 2 O emulsion with the increase in water cut was confirmed. CO 2 /H 2 O emulsions with lower water cuts presented higher apparent viscosity, while the optimal plugging capacity of CO 2 /H 2 O emulsion occurred at a certain water cut. Eventually, the displacement using CO 2 /H 2 O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO 2 in long sand pack and core tests, respectively. This work may provide guidelines for EOR using CO 2 emulsions with high water cut.
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Small Methods
·
2023
·
IF 12.4
Qi Tang,Yongbin Wang,Ningjun Chen,Ben Pu,Yue Qing,Mingzhe Zhang,Jia Bai,Yi Yang,Jin Cui,Yan Liu,Bin Zhou,Weiqing Yang
Nb 4 C 3 T x MXene has shown extraordinary promise for various applications owing to its unique physicochemical properties. However, it can only be synthesized by the traditional HF-based etching method, which uses large amounts of hazardous HF and requires a long etching time (> 96 h), thus limiting its practical application. Here, an ultra-efficient and environmental-friendly H 2 O-assisted supercritical etching method is proposed for the preparation of Nb 4 C 3 T x MXene. Benefiting from the synergetic effect between supercritical CO 2 (SPC-CO 2 ) and subcritical H 2 O （SBC-H 2 O）, the etching time for Nb 4 C 3 T x MXene can be dramatically shortened to 1 h. The as-synthesized Nb 4 C 3 T x MXene possesses uniform accordion-like morphology and large interlayer spacing. When used as anode for Li-ion battery, the Nb 4 C 3 T x MXene delivers a high reversible specific capacity of 430 mAh g −1 at 0.1 A g −1 , which is among the highest values achieved in pure-MXene-based anodes. The superior lithium storage performance of the Nb 4 C 3 T x MXene can be ascribed to its high conductivity, fast Li + diffusion kinetics and good structural stability.
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INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Bo Wang,Kai Li,Cheng-bo Zhang,Ting Huang,Ti-peng Wang,Qiang Lu
A series of regenerated cellulose (RC) were prepared by a H 3 PO 4 -H 2 O system with different H 3 PO 4 concentrations. The effects of H 3 PO 4 concentrations on the physicochemical properties of RCs were studied, including crystallinity index (CrI), hydrogen bond energy (E H ), accessibility, and degree of polymerization (DP). The catalytic pyrolysis experiments of RCs were executed with a pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) instrument and a lab-scale device, to investigate the regulatory function of cellulose structure on the LGO formation. The results indicated that the H 3 PO 4 -H 2 O system could transform the cellulose crystal form from Ⅰ to amorphous form, reduce its CrI and E H significantly, improve its accessibility, while had slight effects on the DP. These changes made RC more appropriate for the selective preparation of LGO, and the corresponding optimal catalyst loading and pyrolytic temperature were also decreased significantly. With phosphoric acid activated carbon as the catalyst, the highest yield of LGO from RC in Py-GC/MS experiments reached 21.50 wt% at catalyst/cellulose (Cat/Cel) ratio of 1/5 and 270 °C, which was much higher than the 18.16 wt% of LGO gained from untreated cellulose at Cat/Cel ratio of 1/3 and 300 °C. In the lab-scale device, the maximum LGO yield from RC was 17.09 wt% at 270 °C and Cat/Cel ratio of 1/6.
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Reaction Chemistry & Engineering
·
2022
·Vol. 8
·期 4
·778-783
·
IF 5.2
Huan Liu,Yi-Xuan Yao,Hong-Yan Shang,Da Yang,Yuan-Yu Tian
The tandem hydroformylation–acetalization of olefins with H2O as the hydrogen source was accomplished over an Ir(I)-catalyst using the phased warming strategy. Due to the release of protons by AlCl3-hydrolysis equilibrium, the tandem reaction was significantly enhanced. The conversion of 1-hexene was 100% and the selectivity for oxo-products was 89%, where 91% of acetals was obtained. Moreover, the hydrogenation by-products were detected to be less than 3%, showing that H2O as the hydrogen source inhibited the hydrogenation of olefins in this tandem reaction. Moreover, isotope-labeling experiments confirmed that water was the hydrogen source, and the key Ir–H active species for hydroformylation were captured by high-pressure 1H NMR spectroscopy analyses.
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ACS Omega
·
2019
·
IF 2.584
Xinru Mu,Ganyu Zhu,Xu Li,Shaopeng Li,Xiaokang Gong,Huiquan Li,Guoxin Sun
Wet-process phosphoric acid is a fundamental process in the fertilizer industry. The influence of impurities on crystallization kinetics of CaSO4 was investigated in the Ca(H2PO4)2–H2SO4–H3PO4–H2O system using a mixed suspension mixed product removal crystallizer. Effects of Si, Al, Fe, Mg, K, and Na on crystal morphology and structure were examined in the highly acidic system through scanning electron microscopy and high-resolution transmission electron microscopy. Results show that the increase of Mg, K, and Na content facilitates crystal growth. Si, Al, and Fe are beneficial to CaSO4 crystal growth at a certain concentration range. Impurities also affect the crystal morphology, and the addition of Si, Fe, and Na promotes the formation of needle-like crystals compared with other impurities. X-ray diffraction results show that the preferred crystal growth direction is (020), and the interplanar spacing of the crystals is affected by the element radius of the impurities.
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APPLIED CATALYSIS A-GENERAL
·
2019
·
IF 4.63
Zhiwei Wang,Sha Li,Shaohua Xie,Yuxi Liu,Hongxing Dai,Guangsheng Guo,Jiguang Deng
Volatile organic compounds (VOCs) cause damage to atmospheric environment and human health. Supported noble metal catalysts are widely used to control VOCs emissions. The high cost, and low H 2 O-, CO 2 -, and SO 2 -resistance of such catalysts are worthy to be improved. Herein we fabricated Ce-, V-, or W-doped TiO 2 supported ultralow loading Pt catalysts via the in-situ molten salt method, and evaluated their catalytic performance for acetone (major pollutants in pharmaceutical industry) removal. Under the present reaction conditions, all the catalysts exhibited high catalytic activity and stability for acetone oxidation , with the temperature required 90% acetone conversion being of 245 °C over 0.57 wt% CeO 2 -0.05 wt% Pt/TiO 2 . The doping of Ce, V, or W enhanced the H 2 O-, CO 2 -, and SO 2 -tolerance ability of 0.05 wt% Pt/TiO 2 . More than 85 %85%, 70%, or 60% of acetone could be removed even in the presence of 20 vol% water vapor, 10 vol% CO 2 , or 100 ppm SO 2 , respectively. The improvement in SO 2 -tolerance ability was due to the inhibition of SO 2 adsorption and oxidation activity as well as Ti(SO 4 ) 2 or TiOSO 4 formation. Acetone complete oxidation over 0.57 wt% CeO 2 -0.05 wt% Pt/TiO 2 would follow the pathway: adsorbed acetone molecules → acetic acid and formic acid → carbonate species → CO 2 and H 2 O. The present supported Pt catalysts might be suitable for oxygenated VOCs removal.
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Coatings
·
2018
·Vol. 8
·期 2
·78
·
IF 2.35
Shichao Zhao,Jiaxin Weng,Shengzhong Jin,Yanfei Lv,Zhenguo Ji
Molybdenum disulfide (MoS2) layers show excellent optical and electrical properties and have many potential applications. However, the growth of high-quality MoS2layers is a major bottleneck in the development of MoS2-based devices. In this paper, we report a chemical vapor transport deposition method to investigate the growth behavior of monolayer/multi-layer MoS2using water (H2O) as the transport agent. It was shown that the introduction of H2O vapor promoted the growth of MoS2by increasing the nucleation density and continuous monolayer growth. Moreover, the growth mechanism is discussed.Keywords:chemical vapor transport deposition;molybdenum disulfide;monolayer;water;mechanism
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APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Xiaoqian Guo,Feng Guo,Yishan Li,Zhangqin Zheng,Zhexu Xing,Zihan Zhu,Ting Liu,Xin Zhang,Ying Jin
Dehydration of D-xylose to yield furfural was carried out using bimetallic salts of a heteropolyacid as the catalyst at 160–220 °C in the DMSO/H 2 O mixtures. The effect of Sn/Cs molar ratio of the bimetallic salts of 12-tungstophosphoric acid (PW) obtained by ultrasound-assisted coprecipitation on dehydration of D-xylose was investigated. The resultant catalysts were characterized by X-ray diffraction, N 2 adsorption, field emission scanning electron microscopy and energy dispersive X-ray (EDX). It was found that the Sn-Cs codoped PW catalysts retained the Keggin crystal structure of PW. Sn 0.625 Cs 0.5 PW was the most active catalyst in the dehydration of D-xylose into furfural. The maximum D-xylose conversion (close to 100 wt %) and furfural yield (63 wt %) were achieved at 200 °C for 3 h in DMSO/H 2 O mixtures. It was found that 16.7 wt % Sn 0.625 Cs 0.5 PW on a chitosan-derived support displayed similar catalytic activity to that of Sn 0.625 Cs 0.5 PW and good stability after recycling six times.
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Plasma Processes and Polymers
·
2023
·Vol. 20
·期 5
·2200228
·
IF 3.5
Siyuan Sui,Hongmei Sun,Guohua Ni,Yafeng Liu,Huan Zheng,Tao Sun,Ling Kong,Zhongyang Ma,Fangli Yuan
The surface of polytetrafluoroethylene (PTFE) is activated by argon (Ar), Ar mixed with water vapor (Ar-H 2 O), and a mixture of Ar, water vapor, and ammonia (Ar-H 2 O-NH 3 ) plasmas and then grafted onto polymerized dopamine/ethylene imine and immobilized heparin. Oxygen-containing functional groups are all introduced onto the PTFE surface treated by three types of plasma. The amount of oxygen grafted is the highest in samples treated with Ar-H 2 O-NH 3 plasma compared to that treated with Ar-H 2 O plasma. An increase in the content of oxygen grafted onto PTFE contributes to an increase in the thickness and cross-linking bond of the polymeric interlayer and then raises the density of the heparin coating. The thickness of the polydopamine/polyethylenimide intermediate layer on the surface of PTFE treated with Ar-H 2 O-NH 3 plasma is 4.8 ± 0.3 μm, and the density of the immobilized heparin coating was 95 μg/cm 2 .
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Nature Communications
·
2022
·Vol. 13
·期 1
·1-11
·
IF 17.694
Shangguan Wenchao,Liu Qing,Wang Ying,Sun Ning,Liu Yu,Zhao Rui,Li Yingxuan,Wang Chuanyi,Zhao Jincai
Achieving CO 2 reduction with H 2 O on metal photocatalysts and understanding the corresponding mechanisms at the molecular level are challenging. Herein, we report that quantum-sized Au nanoparticles can photocatalytically reduce CO 2 to CO with the help of H 2 O by electron-hole pairs mainly originating from interband transitions. Notably, the Au photocatalyst shows a CO production rate of 4.73 mmol g −1 h −1 (~100% selectivity), ~2.5 times the rate during CO 2 reduction with H 2 under the same experimental conditions, under low-intensity irradiation at 420 nm. Theoretical and experimental studies reveal that the increased activity is induced by surface Au–O species formed from H 2 O decomposition, which synchronously optimizes the rate-determining steps in the CO 2 reduction and H 2 O oxidation reactions, lowers the energy barriers for the *CO desorption and *OOH formation, and facilitates CO and O 2 production. Our findings provide an in-depth mechanistic understanding for designing active metal photocatalysts for efficient CO 2 reduction with H 2 O.
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JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 28
·13632-13646
·
IF 4.682
Zhu Wenhao,Wu Zhenxu,Wang Peng,Liu Tianyi,Guo Min,Ji Jiansong,He Mingfeng,Wang Haifeng,Zhang Peibiao
Within brain tissue engineering, stem cell implantation assisted by biodegradable injectable scaffolds is a crucial method. However, implanted scaffolds, especially microcarriers, may translocate due to the fluidity of the materials. Therefore, the development of an MRI contrast enhancement microcarrier, which could noninvasively trace the location of the implant in vivo, is necessary to guide the evaluation of treatment prognosis. In this study, GdPO 4 ·H 2 O nanoparticles were utilized as the dispersed phase to endow PLGA microcarriers with T1-weighted MRI contrast ability. By adjusting the dispersed phase of Gd compound nanoparticle in PLGA Matrix, a cross-comparison experiment between MRI contrast enhancement imaging and biocompatibility was conducted, and 0.8% Gd was found to be the most suitable rate for preparing nano-composites. Moreover, 0.8% Gd/PLGA microcarriers were suspension-cultured with stem cells in vitro and implanted into traumatic brain injury rats in vivo. Excellent cytocompatibility and enhancement of the T1 phase of MRI were confirmed. This work created a T1-weighted MRI contrast-enhanced microcarrier, which provides a clinical noninvasive tracing cell scaffold for brain tissue engineering.
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CHEMICAL PAPERS
·
2020
·Vol. 74
·期 11
·3987-3993
·
IF 1.68
Pan Binfeng,Zhang Zhimin,Lu Xuchen
Abstract The reaction between rare earth oxychloride (REOCl) and water was investigated. X-ray diffractometer, volumetric titrations, FTIR spectrograph and scanning electron microscope were used to determine the reaction process and the reaction products. It was found that the reaction could be concluded as follows: 5REOCl(s) + 5H 2 O(l) = 2RE 2 (OH) 5 Cl(s) + RE 3+ (aq) + 3Cl − (aq). Based on this reaction, a new method for determining the purity of anhydrous rare earth chloride was proposed. Compared with the conventional method, the maximum absolute error decreased from 22 to < 1% and the maximum relative error decreased from 111 to < 4% under the experimental conditions. Graphic abstract
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危险品化学品经营许可证（带存储）