JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Chuyuan Huang,Xianfeng Chen,Bihe Yuan,Hongming Zhang,Sheng Shang,Qi Zhao,Huaming Dai,Song He,Ying Zhang,Yi Niu
Flame propagation characteristics of wood dust deflagration and suppression mechanism of ultrafine powders are investigated systematically. The deflagration reaction intensity of wood dust increases firstly and then decreases with the increase in dust cloud concentration. This is due to factors such as oxygen supply, positive feedback among flame characteristic parameters. Thus, there is an equivalent dust concentration for greatest deflagration intensity. Nano-sized ultrafine zirconium hydroxide (Zr(OH) 4 ) and silicon dioxide (SiO 2 ) powder are introduced to suppress wood dust deflagration at the equivalent concentration. It is found that Zr(OH) 4 has a suppression effect of endothermic decomposition to generate zirconia (ZrO 2 ), dilution of oxygen and absorption of free radicals; while SiO 2 exerts suppression effect due to its high melting point and heat absorption. The suppression performance of Zr(OH) 4 is better than that of SiO 2 . This is because that Zr(OH) 4 and ZrO 2 have a catalytic carbonization effect. It can not only improve thermal stability of wood particles by catalyzing production of high-temperature resistant residuals, but also promote the formation of catalytic sites to reduce crystallite size of carbon layer on wood particles surface, weakening heat and mass transfer between particles.
研究领域:
安全工程
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燃烧学
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粉尘爆炸防控
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材料化学
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热力学
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DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2022
·
IF 1.097
Shaoxiong Wu,Lianyuan Wang,Haiyan Zhu,Jing Liang,Liang Ge,Cong Li,Ting Miao,Jian Li,Zhenxing Cheng
Chemical warfare agents, such as nerve agents (GD and VX) and blister agents (HD), have strong toxicities to mankind. In recent years, zirconium-based metal-organic frameworks have been found to be attractive materials for chemical warfare agent degradation. Among them, metal-organic framework-808 (MOF-808) and porous coordination network-222 (PCN-222) were the best. However, few papers pay attention to their practical application. In this work, we prepared MOF-808 and PCN-222 using water phase and organic solvothermal methods, respectively. Their performance for the catalytic degradation of chemical warfare agents under practical decontamination conditions was studied. The results showed that MOF-808 displayed a high potency for catalytic hydrolysis of VX (10,000 mg L−1) in unbuffered solution. PCN-222 exhibited weaker reactivity with a half-life (t1/2) of 28.8 min. Their different performances might stem from the different connectivity of the Zr6 nodes and framework structures. The results illustrated that the hydrolysis of high-concentration GD required a strong alkaline buffer to neutralize the hydrolysis product of hydrofluoric acid (HF) to avoid catalyst poisoning. When H2O2 was used as the oxidant instead of O2, both zirconium-based metal-organic frameworks performed with effective catalytic potency for HD degradation without any special lighting and so was suitable for practical application, whereas the products obtained from HD, such as HDO2 and V-HDO2, still possessed vesicant toxicity. Overall, MOF-808 prepared via a water-phase synthesis performed with effective catalysis for the degradation of high-concentration VX, GD, and HD with t1/2 of < 0.5, 3.1 and 2.2 min, respectively, exhibiting its potential for practical applications.
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高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Fukun Li,Ronghe Yang,Ziting Du,Jinhang Dai,Xingmin Wang,Ning Li,Jie Zhang,Xianming Zhang,Yunqi Liu,Haifeng Gong,Hong Yin,Zhenping Cai
γ-Valerolactone (GVL) is considered as a versatile platform chemical obtained from biomass refinery. In this study, eco-friendly group III metal (Sc, Y, La) triflates were examined as homogeneous catalysts for microwave-assisted transfer hydrogenation of ethyl levulinate (EL) to GVL under mild conditions. Experimental results revealed that the selectivity of GVL has a positive relationship with the Lewis acidity of metal ion, which is related to effective charge density of the metal center (3.23, 2.81, 2.60 for Sc 3+ , Y 3+ , La 3+ , respectively). The stronger Lewis acidity of metal ion, the higher catalytic activity of MPV reduction. Among these catalysts, Sc(OTf) 3 exhibited the best catalytic activity, achieving 98.4% EL conversion and 92.4% GVL yield at 140 °C in 3.0 h. Furthermore, Sc(OTf) 3 showed high stability and recyclability for at least ten reaction cycles. In addition, a plausible reaction pathway and mechanism were proposed.
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高影响因子
APPLIED CATALYSIS A-GENERAL
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2022
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IF 5.723
Meng Zhang,Junfeng Zhang,Qingde Zhang,Yizhuo Han
The surface reactive oxygen species over Y 2 O 3 -ZrO 2 supports were tuned by regulating the interaction between Y and Zr via modulating the zirconium precursors. It was revealed that the content of the surface adsorbed oxygen species (SAOS) over the catalyst with ZrO 2 precursor was the highest, followed by the catalysts with Zr(OH) 4 and ZrO(NO 3 ) 2 ·2H 2 O precursors. The difference of the Y-Zr interaction influenced the reactive oxygen species and the support structure and morphology. However, Ni dispersion was determined by the existence of the isolated Y 2 O 3 due to the enhanced metal-support interaction. High Ni dispersion and abundant surface adsorbed oxygen species were beneficial to promote CH 4 and CO 2 reactivity. Nevertheless, CH 4 dissociation facilitated by the SAOS was more remarkable than CO 2 activation at low temperature. Thus, the improvement of the SAOS on carbon-resistant ability of the catalyst was only achieved at high temperature through balancing the carbon formation and elimination.
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高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2023
·Vol. 29
·期 52
·e202300950
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IF 4.3
Fukun Li,Ronghe Yang,Zheng Tian,Ziting Du,Jinhang Dai,Xingmin Wang,Ning Li,Jie Zhang
Graphical Microwave-assisted one pot cascade transformation of furfural to γ-valerolactone catalyzed by Sc(OTf) 3 . γ-Valerolactone (GVL) is considered as a star biochemical which can be used as a green solvent, fuel additive and versatile organic intermediate. In this study, metal triflate (M(OTf) n ) was utilized as the catalyst for one-pot transformation of furfural (FF) to GVL in alcohol media under microwave irradiation. Alcohol plays multiple functions including solvent, hydrogen donor and alcoholysis reagent in this cascade reaction process. And process efficiency of GVL production from FF upgrading is strongly related to the effective charge density of selected catalyst and the reduction potential of selected alcohol. Complex (OTf) n -M−O(H)R, presenting both Brønsted acid and Lewis acid, is the real catalytic active species in this cascade reaction process. Among various catalysts, Sc(OTf) 3 exhibited the best catalytic activity for GVL production. Various reaction parameters including the Sc(OTf) 3 amount, reaction temperature and time were optimized by the response surface methodology with the central composite design (RSM-CCD). Up to 81.2 % GVL yield and 100 % FF conversion were achieved at 143.9 °C after 8.1 h in the presence of 0.16 mmol catalyst. This catalyst exhibits high reusability and can be regenerated by oxidative degradation of humins. In addition, a plausible cascade reaction network was proposed based on the distribution of product.
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DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
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2018
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IF 5.116
Yongxiang Chen,Yunjiao Li,Wei Li,Guolin Cao,Shuyun Tang,Qianye Su,Shiyi Deng,Jia Guo
The stabilities of the host and interfacial structure for layered LiNi x Co y Mn 1-x-y O 2 cathode materials are critical for their electrochemical properties, especially at high voltage. This study reports the synergetic effect of the Zr and Ti elements on the LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode material (NCM523). The as-obtained Zr/Ti modified LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode material shows the excellent electrochemical performance at high voltage. It delivers 167.3 mAh·g −1 at 1 C over 3.0–4.4 V corresponding 94.20% capacity retention after 200 cycles. Moreover, the rate capability of Zr/Ti co-modified NCM523 at 16 C (3.0–4.4 V) rises to 139.4 mAh·g −1 and corresponding capacity retention (vs. 0.5 C) is 79.57%. In addition, its capacity retention reaches to 91.71% after 100 cycles at 1 C rate even at 3.0–4.6 V. Such superior electrochemical performances are ascribed to the Zr doping and Ti modification. The synergetic modifications of the Zr/Ti elements not only stabilize the crystal structure, but also absorb the lithium residues to form mixed Li 4 Ti 5 O 12 /Li 2 TiO 3 coating layers, which strengthen the stability of the interfacial structure and the kinetic characteristics of the cathode materials.
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2018
·Vol. 102
·期 3
·1414-1424
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IF 2.956
Yaowu Wei,Tao Zhang,Qi Zhang,Bingqiang Han,Nan Li
Improving the hydration resistance of CaO aggregates is the key to successful application of lime-based refractories in metallurgical industry. Additive Zr(OH) 4 and Al(OH) 3 were introduced in the preparation of CaO granules using granulation equipment and calcination method in this study. The results showed that the hydration resistance of CaO granules was improved significantly, especially for granules with 0.6 wt.% Zr(OH) 4 and 0.9 wt.% Al(OH) 3 , respectively. The shell of CaO granules was relatively dense after calcination and the volume of open pores of CaO granules decreased from 3.56 × 10 −2 to 1.80 × 10 −2 cm 3 /g when additive was introduced. Zr(OH) 4 and Al(OH) 3 have the opposite effect on the closed porosity of CaO granules, the closed porosity of CaO granules was decreased with Zr(OH) 4 addition, but increased with Al(OH) 3 addition.
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高影响因子
APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Biao Zhao,Yong Men,Anni Zhang,Jinguo Wang,Rong He,Wei An,Shenxiao Li
The effects of zinc precursors on the performance of bifunctinal Zn 1 Zr 10 O x catalysts were investigated for direct conversion of bio-ethanol into isobutene (ETIB). The catalyst derived from zinc acetate precursor exhibited full ethanol conversion and 50% isobutene yield at a WHSV of 0.38 g ethanol g cat −1 h −1 at 450 °C. Characterization results based on XRD, FT-IR, UV–vis, Raman, BET, CO 2 -TPD, NH 3 -TPD, H 2 -TPR, and XPS revealed that Zn 1 Zr 10 O x catalyst prepared by zinc acetate precursor with large anion size possessed the highest zinc dispersion and the strong ZnO-ZrO 2 interaction, and presented the highest ethanol reaction rate and isobutene yield under kinetic control regime. The beneficial effect of larger anion size was rationalized by the shielding effect in the incorporation model dominated by the size of capping anion in zinc precursors. Further durability test showed that the catalyst exhibited slow deactivation against coking formation while isobutene yield was maintained above 45% for 18 h.
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高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Guangce Jiang,Yinghui Hu,Guoqiang Xu,Xindong Mu,Huizhou Liu
Hydrodeoxygenation of phenolic components in pyrolysis bio-oil is considered to be a potential strategy for producing renewable aromatic chemicals. The key issue of this process is the establishment of an effective catalytic system that can cleave the CAr–O bonds without affecting the aromatic structure. To achieve this goal, an efficient heterogeneous catalyst with solid acid support (WOx/ZrO2) and active metal (Ru) was prepared in this study. The Ru–WOx/ZrO2 catalyst can effectively convert model phenolic compounds into aromatic hydrocarbons. For a mixed phenolic sample, the conversion to and selectivity for arenes were all around 90%. The good selectivity was proved to be strongly related to the surface adsorption and acid properties of the catalyst as well as the reaction pathway. Moreover, the hydrodeoxygenation of a pretreated bio-oil was also conducted and presented a satisfactory yield of arenes at 240 °C with 1 MPa of H2 reacted for 5 h. The depolymerization of high-molecular-weight phenolic oligomers was found to be significant during the catalytic process, which further enhanced the yield of aromatic monomers.
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高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Ying Gao,Yong Liu,Lingling Gao,Jinxing Long
An effective strategy is proposed here for transfer hydrogenation of alkyl levulinate to γ-valerolactone (GVL) using a UiO-66 framework modified with phosphotungstate ionic liquid (UiO-66@IL(HPW)). Due to the intensive influence of ionic liquid fragment, the modification significantly enhances the catalytic activity of UiO-66@IL(HPW), leading to a complete conversion of ethyl levulinate with over 93.1% selectivity for GVL. Characterizations techniques, including XRD, N 2 absorption/desorption, SEM, FT-IR, pyridine FT-IR, NH 3 -TPD and CO 2 -TPD, confirm that while the basic structure of UiO-66-NH 2 is insignificantly changed, the introduction of the ionic liquid greatly improves the acidic/base properties of the catalyst. XAFS and XPS results reveal an intensive interaction between the N and W species in UiO-66@IL(HPW), and the formed W-N/O moiety is responsible for the enhanced catalytic activity. In addition, a plausible catalytic mechanism is proposed based upon in situ DRIFTS and density functional theory (DFT) calculations, highlighting the crucial role of ionic liquid fraction within the UiO-66 ligand. Therefore, this work would contribute to the valorization of biochemicals.
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高影响因子
RSC Advances
·
2017
·Vol. 7
·期 14
·8567-8574
·
IF 3.108
Jiachun Chai,Shanhui Zhu,Youliang Cen,Jing Guo,Jianguo Wang,Weibin Fan
One-pot hydrogenolysis of cellulose to ethylene glycol (EG) was carried out on WO3-based catalysts combined with Ru/C. To probe the active catalytic site for breaking the C–C bond of cellulose, a series of WO3–ZrO2 (WZr) catalysts were synthesized and systematically characterized with XRD, Raman, UV-Vis, H2-TPR, DRIFS and XPS techniques and N2 physisorption experiment. It was found that the WO3 crystallites became more easily reduced to W5+–OH species with increasing crystallite size or tungsten surface density of the WZr catalyst owing to the decrease of their absorption edge energy (AEE) originating from weakening their interaction with ZrO2 support. This, as a result, gave higher EG yield at higher tungsten surface density. The structure–activity relationship of the WZr catalyst reveals that the active catalytic site for cleaving the C2–C3 bond of the glucose molecule is the W5+–OH species.
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高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2017
·
IF 1.174
Yuedong Zhou,Fengfu Li,Junwei Liu,Zhi Yun,Xia Gui
The liquid phase ring-opening of octamethylcy-clotetrasiloxane (D 4 ) was investigated over Pt-H 2 SO 4 /Zr-montmorillonite catalyst. Montmorillonite (Mt), Zr-Mt, H 2 SO 4 /Mt, H 2 SO 4 /Zr-Mt and Pt-H 2 SO 4 /Zr-Mt were also detected for evaluation. The catalysts were characterized by X-ray fluorescence, X-ray diffraction, nitrogen adsorption–desorption, NH 3 -TPD and pyridine-FTIR measurements. In comparison to activate clay which is used in the industry of catalyst, Zr-Mt catalyst displayed stronger acidity and more excellent catalytic activity in the polymerization of D 4 , polymethylhydrosiloxane (D 4 H ) and hexamethyldisiloxane (MM) to low-hydro silicone oil. Relative to Zr-Mt, the acidity of H 2 SO 4 /Zr-Mt was noticeably improved and the catalyst exhibited a higher capability of ring-opening of D 4 conversion and yield of low-hydro silicone oil. To enhance the stability of H 2 SO 4 /Zr-Mt catalyst, a small amount of metals (Pt) was doped. The nitrogen adsorption–desorption results indicated that pore textural parameters of the Pt-H 2 SO 4 /Zr-Mt had not changed with larger specific surface area. Compared with H 2 SO 4 /Zr-Mt, the total acidity of Pt-H 2 SO 4 -Zr/Mt catalyst retained, but the content of the Brønsted acid increased and the content of the Lewis acid decreased. The Pt-H 2 SO 4 -Zr/Mt catalyst displayed higher catalyst reproducibility. After 40 h reaction of polymerization, the yield of low-hydro silicone oil decreased from 93% to 42% over H 2 SO 4 /Zr-Mt catalyst, while the yield of low-hydro silicone oil reduced from 93% to 78% over Pt-H 2 SO 4 /Zr-Mt catalyst. A sharp decrease in catalytic activity after 35 h of Pt-H 2 SO 4 /Zr-Mt catalyst was detected. Furthermore, Pt-H 2 SO 4 /Zr-Mt was completely regenerated under appropriate condition and appeared good repeatability in the D 4 , D 4 H and MM to low-hydro silicone oil.
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高影响因子
危险品化学品经营许可证（带存储）