The kinetics of liquid-phase hydrogenation of toluene catalyzed by MlNi_5 was studied by investigating the influences of the reaction temperature and pressure on the mass transfer-reaction processes inside the slurry....The kinetics of liquid-phase hydrogenation of toluene catalyzed by MlNi_5 was studied by investigating the influences of the reaction temperature and pressure on the mass transfer-reaction processes inside the slurry. The results show that the reaction rate accelerates when the reaction temperature increases, and reaches its maximum at about 490 K, but if temperature is higher than 510 K, the reaction rate decreases rapidly. The whole reaction process is controlled by the reaction at the surface of the catalyst particles. The mass transfer resistance at gas-liquid interface and that from the bulk liquid phase to the surface of the catalyst particle can be neglected. The apparent reaction rate is zero order for toluene concentration and first order for hydrogen concentration in the liquid phase. The kinetic model is obtained. The kinetic model fits the experimental data very well. The apparent activation energy of the hydrogen absorption reaction of MlNi_5-toluene slurry system is 41.01 kJ·mol^(-1).展开更多
The great potential of gold catalysts for chemical conversions in both industrial and environmental concerns has attracted increasing interest in many fields of research.Gold nanoparticles supported by metal oxides wi...The great potential of gold catalysts for chemical conversions in both industrial and environmental concerns has attracted increasing interest in many fields of research.Gold nanoparticles supported by metal oxides with high surface area have been recognized as highly efficient and effective green heterogeneous catalyst even at room temperature under normal reaction conditions,in gas and liquid phase reactions.In the present review,we discuss the recent development of heterogeneous,supported monometallic gold catalysts for organic transformations emphasizing mainly liquid phase hydrogenation reactions.Discussions on the catalytic synthesis procedures and the promoting effect of other noble metals are omitted since they are already worked out.Applications of heterogeneous,supported monometallic catalysts for chemoselective hydrogenations in liquid phase are studied including potential articles during the period 2000–2013.展开更多
The activation of HCl by cationic Au in the presence of C2H2 is important for the construction of active Au sites and in acetylene hydrochlorination.Here,we report a strategy for activating HCl by the Au-based support...The activation of HCl by cationic Au in the presence of C2H2 is important for the construction of active Au sites and in acetylene hydrochlorination.Here,we report a strategy for activating HCl by the Au-based supported ionic liquid phase(Au–SILP)technology with the[N(CN)2^–]anion.This strategy enables HCl to accept electrons from[N(CN)2^–]anions in Au–[N(CN)2^–]complexes rather than from pure[Bmim][N(CN)2],leading to notable improvement in both the reaction path and the stability of the catalyst without changing the reaction triggered by acetylene adsorption.Furthermore,the induction period of the Au–SILP catalyst was shown to be absent in the reaction process due to the high Au(III)content in the Au(Ⅲ)/Au(Ⅰ)site and the high substrate diffusion rate in the ionic liquid layer.This work provides a facile method to improve the stability of Au-based catalysts for acetylene hydrochlorination.展开更多
Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and su...Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3.展开更多
Au/FeOx-TiO2,prepared by deposition-precipitation method,is an efficient and stable catalyst for the liquid phase selective hydrogenation of phthalic anhydride to phthalide under mild reaction conditions.
For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified ...For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified well by liquid phase catalytic oxidation (LCO), and the sulfur resource could also be recovered. The absorption solution was prepared by FeCl3 and sulfosalicylic acid. Under the experimental conditions, the conversion of H2S to S could be maintained above 94% at 60 ℃. In order to enhance the economical efficiency of LCO method, the absorption solution was modified by doping Ce, and a series of experiments were designed to investigate its performance. The results showed that the conversion of H2S had no obvious improvement, but above 98% conversion could be gained at 60 ℃, and the H2S conversion rate was enhanced. The optimum addition quality of Ce(NO3)3 was 0.08 g to 50 ml Fe3+ solution.展开更多
We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacet...We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacetylene and superior stability under mild conditions. Supported Pd catalysts are characterized by means of high resolution transmission electron microscopy(HRTEM), Raman, X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and H2 temperature-programmed reduction(H2-TPR).The results clearly show that formation of the strong metal-support interaction(SMSI) between Pd nanoclusters and the defective graphene shell helpfully modifies the selectivity and stability of the Pd-based catalysts.展开更多
Two kinds of nickel nanoparticles (NPs) well-dispersed in aqueous phase have been conveniently prepared by reducing nickel(II) salt with hydrazine in the presence of amino group (-NH2) functionalized ionic liquids:1-(...Two kinds of nickel nanoparticles (NPs) well-dispersed in aqueous phase have been conveniently prepared by reducing nickel(II) salt with hydrazine in the presence of amino group (-NH2) functionalized ionic liquids:1-(3-aminopropyl)-2,3-dimethylimidazolium bromide ([AMMIM][Br]) and 1-(3-aminopropyl)-2,3-dimethylimidazolium acetate ([AMMIM][AcO]).The Ni(0) particles are composed of smaller ones which assemble in a blackberry-like shape.The Ni nanoparticles stabilized with [AMMIM][AcO] are much larger than those stabilized with [AMMIM][Br],and the former unexpectedly give much higher activity in the selective hydrogenation of citral and nitrobenzene (NB) in aqueous phase.The Ni(0) nanocatalysts dispersed in aqueous phase are stable enough to be reused at least five times without significant loss of catalytic activity and selectivity during the catalytic recycles.展开更多
Instead of praises from colleagues,the claim of observation of metallic hydrogen at 495 GPa by Dias and Silvera met much skepticism,and grew into a public debate at the International Conference on High-Pressure Scienc...Instead of praises from colleagues,the claim of observation of metallic hydrogen at 495 GPa by Dias and Silvera met much skepticism,and grew into a public debate at the International Conference on High-Pressure Science and Technology,AIRAPT26.We briefly review this debate,and extend the topic to show that this disputation could be an opportunity to benefit the whole high pressure community.展开更多
The liquid-phase furfural (FAL) hydrogenation to furfuryl alcohol (FOL) and tetrahydrofurfuryl alcohol (THFOL) was investigated using sulfonate group (-SO3H) grafted activated carbon (AC) supported Ni cataly...The liquid-phase furfural (FAL) hydrogenation to furfuryl alcohol (FOL) and tetrahydrofurfuryl alcohol (THFOL) was investigated using sulfonate group (-SO3H) grafted activated carbon (AC) supported Ni catalyst, which was prepared and activated simultaneously by liquid phase reduction method. This functionalized nickel catalyst demonstrated an enhanced catalytic performance for selective hydrogenation of FAL, in which almost 100% FOL (〈80℃) and THFOL (〉100℃) selectivity with complete conversion was obtained, respectively. More importantly, the conversion of transfer hydrogenation of FAL to FOL also can reach almost 100% under optimal conditions (140℃, 4.0h). The effect of -SO3H was evaluated and systematically analyzed by the combination of reaction performance and physico-chemical characterizations. Cycling test proved the prepared catalyst could be recycled and reused for several times without noticeably reducing catalytic activity of hvdrogenation.展开更多
Single atom catalysts(SACs)offer exceptional atom efficiency,activity,and selectivity for many catalytic systems.In recent years,SACs have demonstrated great potential in liquid phase selective hydrogenation.In this r...Single atom catalysts(SACs)offer exceptional atom efficiency,activity,and selectivity for many catalytic systems.In recent years,SACs have demonstrated great potential in liquid phase selective hydrogenation.In this review,we discuss the critical challenge of selective hydrogenation reactions.Meanwhile,we highlight recent achievements in the design and construction of SACs,as well as their application in liquid reactions.Finally,the current issues and future opportunities for development in the field of SACs are given.展开更多
文摘The kinetics of liquid-phase hydrogenation of toluene catalyzed by MlNi_5 was studied by investigating the influences of the reaction temperature and pressure on the mass transfer-reaction processes inside the slurry. The results show that the reaction rate accelerates when the reaction temperature increases, and reaches its maximum at about 490 K, but if temperature is higher than 510 K, the reaction rate decreases rapidly. The whole reaction process is controlled by the reaction at the surface of the catalyst particles. The mass transfer resistance at gas-liquid interface and that from the bulk liquid phase to the surface of the catalyst particle can be neglected. The apparent reaction rate is zero order for toluene concentration and first order for hydrogen concentration in the liquid phase. The kinetic model is obtained. The kinetic model fits the experimental data very well. The apparent activation energy of the hydrogen absorption reaction of MlNi_5-toluene slurry system is 41.01 kJ·mol^(-1).
基金Universiti Kebangsaan Malaysia for the financial support
文摘The great potential of gold catalysts for chemical conversions in both industrial and environmental concerns has attracted increasing interest in many fields of research.Gold nanoparticles supported by metal oxides with high surface area have been recognized as highly efficient and effective green heterogeneous catalyst even at room temperature under normal reaction conditions,in gas and liquid phase reactions.In the present review,we discuss the recent development of heterogeneous,supported monometallic gold catalysts for organic transformations emphasizing mainly liquid phase hydrogenation reactions.Discussions on the catalytic synthesis procedures and the promoting effect of other noble metals are omitted since they are already worked out.Applications of heterogeneous,supported monometallic catalysts for chemoselective hydrogenations in liquid phase are studied including potential articles during the period 2000–2013.
文摘The activation of HCl by cationic Au in the presence of C2H2 is important for the construction of active Au sites and in acetylene hydrochlorination.Here,we report a strategy for activating HCl by the Au-based supported ionic liquid phase(Au–SILP)technology with the[N(CN)2^–]anion.This strategy enables HCl to accept electrons from[N(CN)2^–]anions in Au–[N(CN)2^–]complexes rather than from pure[Bmim][N(CN)2],leading to notable improvement in both the reaction path and the stability of the catalyst without changing the reaction triggered by acetylene adsorption.Furthermore,the induction period of the Au–SILP catalyst was shown to be absent in the reaction process due to the high Au(III)content in the Au(Ⅲ)/Au(Ⅰ)site and the high substrate diffusion rate in the ionic liquid layer.This work provides a facile method to improve the stability of Au-based catalysts for acetylene hydrochlorination.
基金Project(2008ZX07105-002) supported by the Erhai Lake Project of National Science and Technology Major Project in the 11th Five years Plan of China
文摘Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3.
基金support provided by Zhejiang Provincial Natural Science Foundation of China(No.Y405108)the Department of Education of Zhejiang Province of China(No.20051409)
文摘Au/FeOx-TiO2,prepared by deposition-precipitation method,is an efficient and stable catalyst for the liquid phase selective hydrogenation of phthalic anhydride to phthalide under mild reaction conditions.
基金the Natural Science Foundation of Yunnan Province (2001E0011Q)the Science Foundation of The Education Department of Yunnan Province (0142111 and 07Z11402)
文摘For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified well by liquid phase catalytic oxidation (LCO), and the sulfur resource could also be recovered. The absorption solution was prepared by FeCl3 and sulfosalicylic acid. Under the experimental conditions, the conversion of H2S to S could be maintained above 94% at 60 ℃. In order to enhance the economical efficiency of LCO method, the absorption solution was modified by doping Ce, and a series of experiments were designed to investigate its performance. The results showed that the conversion of H2S had no obvious improvement, but above 98% conversion could be gained at 60 ℃, and the H2S conversion rate was enhanced. The optimum addition quality of Ce(NO3)3 was 0.08 g to 50 ml Fe3+ solution.
基金supported by the Ministry of Science and Technology (2016YFA0204100)the National Natural Science Foundation of China (21573254, 21703261 and 91545110)+2 种基金the Youth Innovation Promotion Association (CAS), and the Sinopec China and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09030103)the Chongqing Research Program of Basic Research and Frontier Technology (cstc2016jcyjA0432)Scientific and Technological Research Program of Chongqing Municipal Education Commission (KJ1600328)
文摘We report a nanocarbon material with nanodiamond(ND) core and graphene shell(ND@G) as a support for Pd nanocatalysts. The designed catalyst performed good selectivity of styrene(85.2%) at full conversion of phenylacetylene and superior stability under mild conditions. Supported Pd catalysts are characterized by means of high resolution transmission electron microscopy(HRTEM), Raman, X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and H2 temperature-programmed reduction(H2-TPR).The results clearly show that formation of the strong metal-support interaction(SMSI) between Pd nanoclusters and the defective graphene shell helpfully modifies the selectivity and stability of the Pd-based catalysts.
基金supported by the National Natural Science Foundation of China (20773037)East China University of Science and Technology (YJ0142136)the Commission of Science and Technology of Shanghai Municipality (07PJ14023)
文摘Two kinds of nickel nanoparticles (NPs) well-dispersed in aqueous phase have been conveniently prepared by reducing nickel(II) salt with hydrazine in the presence of amino group (-NH2) functionalized ionic liquids:1-(3-aminopropyl)-2,3-dimethylimidazolium bromide ([AMMIM][Br]) and 1-(3-aminopropyl)-2,3-dimethylimidazolium acetate ([AMMIM][AcO]).The Ni(0) particles are composed of smaller ones which assemble in a blackberry-like shape.The Ni nanoparticles stabilized with [AMMIM][AcO] are much larger than those stabilized with [AMMIM][Br],and the former unexpectedly give much higher activity in the selective hydrogenation of citral and nitrobenzene (NB) in aqueous phase.The Ni(0) nanocatalysts dispersed in aqueous phase are stable enough to be reused at least five times without significant loss of catalytic activity and selectivity during the catalytic recycles.
基金The author acknowledges support from the National Natural Science Foundation of China under Grant Nos.11672274 and 11274281the NSAF under Grant No.U1730248.
文摘Instead of praises from colleagues,the claim of observation of metallic hydrogen at 495 GPa by Dias and Silvera met much skepticism,and grew into a public debate at the International Conference on High-Pressure Science and Technology,AIRAPT26.We briefly review this debate,and extend the topic to show that this disputation could be an opportunity to benefit the whole high pressure community.
基金the National Natural Science Foundation of China (Nos. 51502297, 51372248, and 51432009)Instrument Developing Project of the Chinese Academy of Sciences (No. yz201421)
文摘The liquid-phase furfural (FAL) hydrogenation to furfuryl alcohol (FOL) and tetrahydrofurfuryl alcohol (THFOL) was investigated using sulfonate group (-SO3H) grafted activated carbon (AC) supported Ni catalyst, which was prepared and activated simultaneously by liquid phase reduction method. This functionalized nickel catalyst demonstrated an enhanced catalytic performance for selective hydrogenation of FAL, in which almost 100% FOL (〈80℃) and THFOL (〉100℃) selectivity with complete conversion was obtained, respectively. More importantly, the conversion of transfer hydrogenation of FAL to FOL also can reach almost 100% under optimal conditions (140℃, 4.0h). The effect of -SO3H was evaluated and systematically analyzed by the combination of reaction performance and physico-chemical characterizations. Cycling test proved the prepared catalyst could be recycled and reused for several times without noticeably reducing catalytic activity of hvdrogenation.
文摘Single atom catalysts(SACs)offer exceptional atom efficiency,activity,and selectivity for many catalytic systems.In recent years,SACs have demonstrated great potential in liquid phase selective hydrogenation.In this review,we discuss the critical challenge of selective hydrogenation reactions.Meanwhile,we highlight recent achievements in the design and construction of SACs,as well as their application in liquid reactions.Finally,the current issues and future opportunities for development in the field of SACs are given.