Pd-based catalysts have been extensively studied in the catalytic oxidation of methane,but their longterm stability and water resistance are unsatisfactory as the active sites are susceptible to water toxicity.The add...Pd-based catalysts have been extensively studied in the catalytic oxidation of methane,but their longterm stability and water resistance are unsatisfactory as the active sites are susceptible to water toxicity.The addition of Pt to Pd-based catalysts is found to be the most effective and promising method.However,distinct states of existence of Pt can affect the catalytic performance to different degrees,even negatively.Therefore,the impact mechanism of Pt on Pd-based catalysts needs to be further understood.In this work,A-site defective La_(0.9)AlO_(x)perovskite was used as a support,and the state of Pt in catalysts was regulated by adjusting the introducing sequence of Pd and Pt,It is found that only when Pt is introduced preferentially,the activity and water resistance of the bimetal can be improved.Combining a series of characterization results of the fresh catalysts,reduced catalysts,and the samples after reduction and use,it is found that the higher Pt^(2+)content in the catalyst is the main reason for promoting bimetallic properties,while more Pt0has an inhibitory effect.This work provides a new understanding of the promotion effect of Pt on Pd-Pt bimetal in the catalytic oxidation reaction of methane.展开更多
The one-step hydrotreatment of rubber seed oil to produce hydrocarbon fuels has been carried out via supported Pd-catalyst,and analyzed emphatically some elements affected catalytic cracking process,for example,temper...The one-step hydrotreatment of rubber seed oil to produce hydrocarbon fuels has been carried out via supported Pd-catalyst,and analyzed emphatically some elements affected catalytic cracking process,for example,temperature,hydrogen partial pressure and dosage of catalyst,etc.Through experimental research,the author found out the appropriate catalytic cracking conditions as follows:310℃ of reaction temperature,2 MPa of hydrogen partial pressure,15 of the ratio of oil to catalyst(m(oil)/m(catalyst)),100 r/min of stirring speed.Under these conditions,effective component of hydrocarbon fuels in the converted oil accounts for 99.49%,and the proportion of C_(8)-C_(16) can reach as high as 79.61%.The converted oil was similar to petroleum-based oil in chemical composition,and can be used for future the aviation biofuels development as the source of raw material because it contains a large amount of hydrocarbon in the range of C_(8)-C_(16).展开更多
基金Project supported by the National Key Research and Development Program(2022YFB3504200)National Natrual Science Foundation of China(22376061,21922602,22076047,U21A20326)+1 种基金Shanghai Science and Technology Innovation Action Plan(20dz1204200)Fundamental Re search Funds for the Central Universities。
文摘Pd-based catalysts have been extensively studied in the catalytic oxidation of methane,but their longterm stability and water resistance are unsatisfactory as the active sites are susceptible to water toxicity.The addition of Pt to Pd-based catalysts is found to be the most effective and promising method.However,distinct states of existence of Pt can affect the catalytic performance to different degrees,even negatively.Therefore,the impact mechanism of Pt on Pd-based catalysts needs to be further understood.In this work,A-site defective La_(0.9)AlO_(x)perovskite was used as a support,and the state of Pt in catalysts was regulated by adjusting the introducing sequence of Pd and Pt,It is found that only when Pt is introduced preferentially,the activity and water resistance of the bimetal can be improved.Combining a series of characterization results of the fresh catalysts,reduced catalysts,and the samples after reduction and use,it is found that the higher Pt^(2+)content in the catalyst is the main reason for promoting bimetallic properties,while more Pt0has an inhibitory effect.This work provides a new understanding of the promotion effect of Pt on Pd-Pt bimetal in the catalytic oxidation reaction of methane.
基金This work was supported by the National Natural Science Foundation of China(No.21266032)International S&T Cooperation Program of China(No.2015DFA60120).
文摘The one-step hydrotreatment of rubber seed oil to produce hydrocarbon fuels has been carried out via supported Pd-catalyst,and analyzed emphatically some elements affected catalytic cracking process,for example,temperature,hydrogen partial pressure and dosage of catalyst,etc.Through experimental research,the author found out the appropriate catalytic cracking conditions as follows:310℃ of reaction temperature,2 MPa of hydrogen partial pressure,15 of the ratio of oil to catalyst(m(oil)/m(catalyst)),100 r/min of stirring speed.Under these conditions,effective component of hydrocarbon fuels in the converted oil accounts for 99.49%,and the proportion of C_(8)-C_(16) can reach as high as 79.61%.The converted oil was similar to petroleum-based oil in chemical composition,and can be used for future the aviation biofuels development as the source of raw material because it contains a large amount of hydrocarbon in the range of C_(8)-C_(16).