This article reports the different steps of the design, development and validation of a process for continuous production of carbon nanotubes (CNTs) via catalytic chemical vapor deposition from the laboratory scale ...This article reports the different steps of the design, development and validation of a process for continuous production of carbon nanotubes (CNTs) via catalytic chemical vapor deposition from the laboratory scale to the industrial production. This process is based on a continuous inclined mobile-bed rotating reactor and very active catalysts using methane or ethylene as carbon source. The importance of modeling taking into account the hydrodynamic, physicochemical and physical phenomena that occur during CNT production in the process analysis is emphasized. The impact of this invention on the environment and human health is taken into consideration too.展开更多
Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass transfer.In this work,the enhanced hydrogenation selectivity was achieved in a rotating packed ...Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass transfer.In this work,the enhanced hydrogenation selectivity was achieved in a rotating packed bed(RPB)reactor with excellent mass transfer efficiency.Aiming to be used under the centrifugal filed,a monolithic catalyst Pd/c-Al_(2)O_(3)/nickel foam suiting for the shape and size of the rotor of RPB reactor was prepared by the electrophoretic deposition method.The mechanical strength of the catalyst can meet the requirement of high centrifugal force in the RPB.The hydrogenation selectivity in the RPB reactor using the 3-methyl-1-pentyn-3-ol hydrogenation system was 3–8 times higher than that in a stirred tank reactor under similar conditions.This work proves the feasibility of intensifying the selectivity of hydrogenation process in the RPB reactor.展开更多
Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward...Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this issue.In this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was evaluated.Major intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed herein.This plasma-catalytic process has bright prospects in the field of antibiotics degradation.展开更多
As a significant index to evaluate the mixing efficiency,studying the concentration distribution is directly related to the intensity of segregation(I_(s)).In this work,the I_(s) of the mixture composed of NaCl soluti...As a significant index to evaluate the mixing efficiency,studying the concentration distribution is directly related to the intensity of segregation(I_(s)).In this work,the I_(s) of the mixture composed of NaCl solutionwater was investigated experimentally in a rotating bar reactor(RBR)by the conductivity method.The results showed that the mixing efficiency was improved along the axial direction from the bottom to the top in the RBR.The concentration distribution at the bottom section was more uneven,and I_(s) was higher compared with the top section,which decreased from 6.53×10^(-5)to 1.57×10^(-7).With the increase of rotational speed from 0 to 700 r·min^(-1),I_s at the bottom and top sections decreased from 4.27×10^(-3)to 7.10×10^(-5)and from 1.93×10^(-3)to 7.29×10^(-7),respectively.The increases flow rate of solution A,and the decreases of concentration of NaCl and flow rate of solution B gave rise to the reduction of I_(s),signifying an improved mixing efficiency.The results revealed that the conductivity method used in this paper has high efficiency and low cost to measure the I_(s),which indicates a promising prospect for estimating reactors'mixing performance.展开更多
A magnetically rotational reactor (MRR) has been developed and used in absorbing benzene emissions. The MRR has a permanent magnet core and uses magnetic ionic liquid [bmim]FeCl4 as absorbent. Benzene emissions were...A magnetically rotational reactor (MRR) has been developed and used in absorbing benzene emissions. The MRR has a permanent magnet core and uses magnetic ionic liquid [bmim]FeCl4 as absorbent. Benzene emissions were carried by N2 into the MRR and were absorbed by the magnetic ionic liquid. The rotation of the permanent magnet core provided impetus for the agitation of the magnetic ionic liquid, enhancing mass transfer and making benzene better dispersed in the absorbent. 0.68 g benzene emissions could be absorbed by a gram of [bmim]FeCl4, 0.27 and 0.40 g/g higher than that by [bmim]PF6 and [bmim]BF4, respectively. The absorption rate increased with increasing rotation rate of the permanent magnet.展开更多
文摘This article reports the different steps of the design, development and validation of a process for continuous production of carbon nanotubes (CNTs) via catalytic chemical vapor deposition from the laboratory scale to the industrial production. This process is based on a continuous inclined mobile-bed rotating reactor and very active catalysts using methane or ethylene as carbon source. The importance of modeling taking into account the hydrodynamic, physicochemical and physical phenomena that occur during CNT production in the process analysis is emphasized. The impact of this invention on the environment and human health is taken into consideration too.
基金supported by the National Natural Science Foundation of China(22022802 and 91934303).
文摘Selective hydrogenation plays an important role in chemical industries,yet its selectivity is usually limited by the mass transfer.In this work,the enhanced hydrogenation selectivity was achieved in a rotating packed bed(RPB)reactor with excellent mass transfer efficiency.Aiming to be used under the centrifugal filed,a monolithic catalyst Pd/c-Al_(2)O_(3)/nickel foam suiting for the shape and size of the rotor of RPB reactor was prepared by the electrophoretic deposition method.The mechanical strength of the catalyst can meet the requirement of high centrifugal force in the RPB.The hydrogenation selectivity in the RPB reactor using the 3-methyl-1-pentyn-3-ol hydrogenation system was 3–8 times higher than that in a stirred tank reactor under similar conditions.This work proves the feasibility of intensifying the selectivity of hydrogenation process in the RPB reactor.
基金This work was supported by the National Natural Science Foundation of China(21725601).
文摘Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this issue.In this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was evaluated.Major intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed herein.This plasma-catalytic process has bright prospects in the field of antibiotics degradation.
基金supported by the National Natural Science Foundation of China(21725601)。
文摘As a significant index to evaluate the mixing efficiency,studying the concentration distribution is directly related to the intensity of segregation(I_(s)).In this work,the I_(s) of the mixture composed of NaCl solutionwater was investigated experimentally in a rotating bar reactor(RBR)by the conductivity method.The results showed that the mixing efficiency was improved along the axial direction from the bottom to the top in the RBR.The concentration distribution at the bottom section was more uneven,and I_(s) was higher compared with the top section,which decreased from 6.53×10^(-5)to 1.57×10^(-7).With the increase of rotational speed from 0 to 700 r·min^(-1),I_s at the bottom and top sections decreased from 4.27×10^(-3)to 7.10×10^(-5)and from 1.93×10^(-3)to 7.29×10^(-7),respectively.The increases flow rate of solution A,and the decreases of concentration of NaCl and flow rate of solution B gave rise to the reduction of I_(s),signifying an improved mixing efficiency.The results revealed that the conductivity method used in this paper has high efficiency and low cost to measure the I_(s),which indicates a promising prospect for estimating reactors'mixing performance.
基金This work was financially supported by the National Natural Science Foundation of China (No.20221603, No.20490200 and No. 20676137)the Scientific Research Foundation for Returned 0verseas Chinese Scholars, the Ministry of Education, and the Chinese Academy of Sciences for international cooperation.
文摘A magnetically rotational reactor (MRR) has been developed and used in absorbing benzene emissions. The MRR has a permanent magnet core and uses magnetic ionic liquid [bmim]FeCl4 as absorbent. Benzene emissions were carried by N2 into the MRR and were absorbed by the magnetic ionic liquid. The rotation of the permanent magnet core provided impetus for the agitation of the magnetic ionic liquid, enhancing mass transfer and making benzene better dispersed in the absorbent. 0.68 g benzene emissions could be absorbed by a gram of [bmim]FeCl4, 0.27 and 0.40 g/g higher than that by [bmim]PF6 and [bmim]BF4, respectively. The absorption rate increased with increasing rotation rate of the permanent magnet.