The preparation of activated carbon from Chinese fir sawdust by zinc chloride activation under both nitrogen atmosphere and vacuum conditions was carded out in a self-manufactured vacuum pyrolysis reactor. The effects...The preparation of activated carbon from Chinese fir sawdust by zinc chloride activation under both nitrogen atmosphere and vacuum conditions was carded out in a self-manufactured vacuum pyrolysis reactor. The effects of the system pressure and the activation condition (nitrogen or vacuum) on pore development were investigated. The results show that both high quality activated carbon and high added-value bio-oil can be obtained simultaneously via vacuum chemical activation. The characteristics of the activated carbons produced under vacuum conditions are better than those prepared under nitrogen atmosphere. The performance parameters of the activated carbon obtained under vacuum conditions are as follows: the pore size distribution is mainly microporous, the Brunauer-Emmett-Teller (BET) surface area is 1 070.59 m^2/g, the microporous volume is 0.502 4 cm^3/g, the average pore size is 2.085 nm, and the iodine adsorption value and the methylene blue adsorption value are 1 142.92 and 131.34 mg/g, respectively. The activated carbon from vacuum chemical activation has developed micropores, and the N2 adsorption equilibrium constant of the corresponding activated carbon gradually increases with the decrease of reaction system pressure.展开更多
A new process for the direct chlorination of 2-chloro-5-methylpyridine to yield 2-chloro-5-chloro-methylpyridine in an airlift loop reactor (ALR) has been studied. Five main reaction conditions including TR, na/ns, cp...A new process for the direct chlorination of 2-chloro-5-methylpyridine to yield 2-chloro-5-chloro-methylpyridine in an airlift loop reactor (ALR) has been studied. Five main reaction conditions including TR, na/ns, cp, Qg and dD/dR were optimized. The average molar yield and purity of 2-chloro-5-chloromethylpyridine obtained were 79% and 98.5% respectively under the optimum operating conditions. Finally, the efficiency for the preparation of 2-chloro-5-chloromethylpyridine with ALR and stirred tank reactor (STR) respectively was compared.展开更多
A new process is developed by using compound Mn as intermediate to produce Cl2from HCl,with the following steps.(1)HCl steam is decomposed by intermediate Mn2O3to produce Cl2and Mn Cl2at 500°C.(2)Produced Mn Cl2i...A new process is developed by using compound Mn as intermediate to produce Cl2from HCl,with the following steps.(1)HCl steam is decomposed by intermediate Mn2O3to produce Cl2and Mn Cl2at 500°C.(2)Produced Mn Cl2is oxidized by water steam to produce Mn O at 450°C.(3)The Mn O compound is oxidized by air to yield Mn2O3.The X-ray diffraction(XRD)crystallite characterization results indicate the high conversion in each step under the optimum experimental conditions.Long term experiments for continuous conversion of HCl to Cl2by using Mn2O3as intermediate in a fixed bed reactor indicate that over 90%of HCl could be converted to Cl2on stream of 30 h.The production of Cl2from HCl with Mn compound as an intermediate and atmospheric steam is a feasible and recyclable process.展开更多
Corrosion behavior of AZ91 magnesium alloy under NaCl particle deposition condition was investigated by gravimetric method and surface analysis technique.It was found that the mass gain increased rapidly at the beginn...Corrosion behavior of AZ91 magnesium alloy under NaCl particle deposition condition was investigated by gravimetric method and surface analysis technique.It was found that the mass gain increased rapidly at the beginning of exposure and then slowly with time.The corrosion morphologies were observed and the results showed that NaCl deposition resulted in the occurrence of localized corrosion.The composition of corrosion product was analyzed using X-ray photo electron spectroscopy.It was suggested that the corrosion product was a mixture of oxide and hydroxide of magnesium and aluminum.展开更多
To investigate the structural features and provide an alternative method for high value-added utilization of coal, Lingwu coal was first extracted with organic solvent at room temperature. Then its extraction residue ...To investigate the structural features and provide an alternative method for high value-added utilization of coal, Lingwu coal was first extracted with organic solvent at room temperature. Then its extraction residue was oxidized in aqueous sodium hypochlorite(ASHC) under mild conditions. The effects of oxidation conditions, such as temperature, reaction time, the ratio of Lingwu coal extraction residue(LCER, g) to ASHC(m L) and p H value, on the product distributions and compositions were investigated. The results of gas chromatography/mass spectrometry(GC/MS) suggested that 53 kinds of methyl esterified products were detected in total, and benzene carboxylic acids were the main oxidation products, while chloro-substituted benzene carboxylic acids were the main by-products. Higher yield and fewer kinds of organic acids could be obtained at lower p H value, especially for the main objective product, benzene carboxylic acids.展开更多
Polyaluminium chloride (PAC) synthetic water was selected as a coagulant and kaolin suspension particles as objects to be removed. Online instruments such as the turbidimeter and particle counter were employed to moni...Polyaluminium chloride (PAC) synthetic water was selected as a coagulant and kaolin suspension particles as objects to be removed. Online instruments such as the turbidimeter and particle counter were employed to monitor the flocculation process online and collect test data. The aim of the experiments was to study the dynamic distribution characteristics of suspension particles in the flocculation process. The 3D flow field in the reacting vessel was also simulated at different slow stirring speeds. The experiments showed that particle collision and aggregation in the flocculation process is in compliance with the Sutherland cluster aggregation model. This study further indicated that under appropriate hydrodynamic conditions, the distribution of turbulent flow in the reactor could be improved to increase the odds of effective particle collision and restrain the breakup of formed flocs by vortex shearing force. A good flocculation effect could therefore be produced.展开更多
文摘The preparation of activated carbon from Chinese fir sawdust by zinc chloride activation under both nitrogen atmosphere and vacuum conditions was carded out in a self-manufactured vacuum pyrolysis reactor. The effects of the system pressure and the activation condition (nitrogen or vacuum) on pore development were investigated. The results show that both high quality activated carbon and high added-value bio-oil can be obtained simultaneously via vacuum chemical activation. The characteristics of the activated carbons produced under vacuum conditions are better than those prepared under nitrogen atmosphere. The performance parameters of the activated carbon obtained under vacuum conditions are as follows: the pore size distribution is mainly microporous, the Brunauer-Emmett-Teller (BET) surface area is 1 070.59 m^2/g, the microporous volume is 0.502 4 cm^3/g, the average pore size is 2.085 nm, and the iodine adsorption value and the methylene blue adsorption value are 1 142.92 and 131.34 mg/g, respectively. The activated carbon from vacuum chemical activation has developed micropores, and the N2 adsorption equilibrium constant of the corresponding activated carbon gradually increases with the decrease of reaction system pressure.
基金Natural Science Foundation of Tianjin(No.013605711)National Natural Science Foundation of China(No.20176040)
文摘A new process for the direct chlorination of 2-chloro-5-methylpyridine to yield 2-chloro-5-chloro-methylpyridine in an airlift loop reactor (ALR) has been studied. Five main reaction conditions including TR, na/ns, cp, Qg and dD/dR were optimized. The average molar yield and purity of 2-chloro-5-chloromethylpyridine obtained were 79% and 98.5% respectively under the optimum operating conditions. Finally, the efficiency for the preparation of 2-chloro-5-chloromethylpyridine with ALR and stirred tank reactor (STR) respectively was compared.
基金Supported by the National High Technology Research and Development Program of China(2011AA060703)the Innovation Funds of institute of processes engineering of Chinese Academy of Sciences(062702)
文摘A new process is developed by using compound Mn as intermediate to produce Cl2from HCl,with the following steps.(1)HCl steam is decomposed by intermediate Mn2O3to produce Cl2and Mn Cl2at 500°C.(2)Produced Mn Cl2is oxidized by water steam to produce Mn O at 450°C.(3)The Mn O compound is oxidized by air to yield Mn2O3.The X-ray diffraction(XRD)crystallite characterization results indicate the high conversion in each step under the optimum experimental conditions.Long term experiments for continuous conversion of HCl to Cl2by using Mn2O3as intermediate in a fixed bed reactor indicate that over 90%of HCl could be converted to Cl2on stream of 30 h.The production of Cl2from HCl with Mn compound as an intermediate and atmospheric steam is a feasible and recyclable process.
基金Projects(50671005,50971093)supported by the National Natural Science Foundation of ChinaProject(2007CB613705)supported by the National Basic Research Program of China
文摘Corrosion behavior of AZ91 magnesium alloy under NaCl particle deposition condition was investigated by gravimetric method and surface analysis technique.It was found that the mass gain increased rapidly at the beginning of exposure and then slowly with time.The corrosion morphologies were observed and the results showed that NaCl deposition resulted in the occurrence of localized corrosion.The composition of corrosion product was analyzed using X-ray photo electron spectroscopy.It was suggested that the corrosion product was a mixture of oxide and hydroxide of magnesium and aluminum.
基金Supported by the National Basic Research Program of China("973" Program,No.2011CB215302)National Natural Science Foundation of China(No.21206188 and 21106177)+1 种基金China Postdoctoral Science Foundation(No.2012M511339)Fundamental Research Funds for the Central Universities(No.2011QNA23)
文摘To investigate the structural features and provide an alternative method for high value-added utilization of coal, Lingwu coal was first extracted with organic solvent at room temperature. Then its extraction residue was oxidized in aqueous sodium hypochlorite(ASHC) under mild conditions. The effects of oxidation conditions, such as temperature, reaction time, the ratio of Lingwu coal extraction residue(LCER, g) to ASHC(m L) and p H value, on the product distributions and compositions were investigated. The results of gas chromatography/mass spectrometry(GC/MS) suggested that 53 kinds of methyl esterified products were detected in total, and benzene carboxylic acids were the main oxidation products, while chloro-substituted benzene carboxylic acids were the main by-products. Higher yield and fewer kinds of organic acids could be obtained at lower p H value, especially for the main objective product, benzene carboxylic acids.
基金Project supported by the National Natural Science Foundation of China (No. 50678047)the Hi-Tech Research and Development Program (863) of China (No. 2006AA06Z305)the National Science and Technology Project of Eleventh Five Years of China (No. 2006BAJ08B05-2)
文摘Polyaluminium chloride (PAC) synthetic water was selected as a coagulant and kaolin suspension particles as objects to be removed. Online instruments such as the turbidimeter and particle counter were employed to monitor the flocculation process online and collect test data. The aim of the experiments was to study the dynamic distribution characteristics of suspension particles in the flocculation process. The 3D flow field in the reacting vessel was also simulated at different slow stirring speeds. The experiments showed that particle collision and aggregation in the flocculation process is in compliance with the Sutherland cluster aggregation model. This study further indicated that under appropriate hydrodynamic conditions, the distribution of turbulent flow in the reactor could be improved to increase the odds of effective particle collision and restrain the breakup of formed flocs by vortex shearing force. A good flocculation effect could therefore be produced.