With increasing amount of unconventional natural gas,the production of ethane,propane and other low alkanes continues to increase.In our previous works,a partially decoupled process(PDP) was proposed for conversion of...With increasing amount of unconventional natural gas,the production of ethane,propane and other low alkanes continues to increase.In our previous works,a partially decoupled process(PDP) was proposed for conversion of ethane based on numerical simulations,which showed higher acetylene and ethylene selectivities than the original partial oxidation process.In the current work,the PDP of ethane for producing acetylene and ethylene was studied experimentally to verify the PDP concept.In the PDP of ethane,coke-oven gas or other cheap gas combusts with stoichiometric oxygen as heat carrier,and ethane is mixed with the heat carrier and undergoes pyrolysis at high temperatures.The jet-in-cross-flow(JICF) reactor was designed and manufactured to realize the PDP.A positioning device of 0.1 mm accuracy and a mass spectrometer were used to measure the spatial profiles of the species concentrations.The maximum combined yield(52.7%) of acetylene and ethylene was obtained even at the condition of heat loss,confirming that the PDP of ethane was advantageous over the partial oxidation process and at least comparable to the steam cracking process.展开更多
In our previous work,a partially decoupled process(PDP)was proposed for efficient conversion of ethane to increase the ethylene yield and a new structural reactor called forward-impinging-back reactor(FIB)was proposed...In our previous work,a partially decoupled process(PDP)was proposed for efficient conversion of ethane to increase the ethylene yield and a new structural reactor called forward-impinging-back reactor(FIB)was proposed for scale-up.In this work,the influence of changing the composition and temperature of the heat carrier was investigated by simulations with detailed chemistry to further increase of the C_(2)(C_(2)H_(2)+C_(2)H_(4))yield in the PDP of ethane.At ideal mixing conditions,the C_(2) yield is 75.3%without steam addition and it is 82.9%at steam addition ratio of β=1.4.In comparison,the C_(2) yield in an FIB reactor is 62.4%without steam addition and it increases to 78.5%with steam addition(β=1.4).The requirement of high mixing efficiency is diminished by steam addition,which is favorable for reactor scale-up.展开更多
Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is...Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods.In this study,we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency(PCE).The liquid crystalline elastomers doped with semiconductor bismuth compounds(Bi-LCE)used in this work exhibited large photothermal actuation with over 35%shrinkage in 5 s at high PCE state,which demonstrated little deformation at low PCE state.Furthermore,the material was capable of being reprogrammed up to 10 times,with only 20 min required for one PCE reversible switch.Based on this switchable PCE effect,the same Bi-LCE film displayed various shape changes through different programmable pattern.Additionally,a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter,cross-section configuration,and surface morphology,which was crucial for microfluidics field.Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics.展开更多
文摘With increasing amount of unconventional natural gas,the production of ethane,propane and other low alkanes continues to increase.In our previous works,a partially decoupled process(PDP) was proposed for conversion of ethane based on numerical simulations,which showed higher acetylene and ethylene selectivities than the original partial oxidation process.In the current work,the PDP of ethane for producing acetylene and ethylene was studied experimentally to verify the PDP concept.In the PDP of ethane,coke-oven gas or other cheap gas combusts with stoichiometric oxygen as heat carrier,and ethane is mixed with the heat carrier and undergoes pyrolysis at high temperatures.The jet-in-cross-flow(JICF) reactor was designed and manufactured to realize the PDP.A positioning device of 0.1 mm accuracy and a mass spectrometer were used to measure the spatial profiles of the species concentrations.The maximum combined yield(52.7%) of acetylene and ethylene was obtained even at the condition of heat loss,confirming that the PDP of ethane was advantageous over the partial oxidation process and at least comparable to the steam cracking process.
基金supported by the National Natural Science Foundation of China(21276135)by Project of Chinese Ministry of Education(113004A).
文摘In our previous work,a partially decoupled process(PDP)was proposed for efficient conversion of ethane to increase the ethylene yield and a new structural reactor called forward-impinging-back reactor(FIB)was proposed for scale-up.In this work,the influence of changing the composition and temperature of the heat carrier was investigated by simulations with detailed chemistry to further increase of the C_(2)(C_(2)H_(2)+C_(2)H_(4))yield in the PDP of ethane.At ideal mixing conditions,the C_(2) yield is 75.3%without steam addition and it is 82.9%at steam addition ratio of β=1.4.In comparison,the C_(2) yield in an FIB reactor is 62.4%without steam addition and it increases to 78.5%with steam addition(β=1.4).The requirement of high mixing efficiency is diminished by steam addition,which is favorable for reactor scale-up.
基金supported by the National Natural Science Foundation of China(62075064)the Key R&D Program of Guangzhou(202007020003)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2021B1515020095,2021A1515110919)the Fundamental Research Funds for the Central Universities(2022ZYGXZR003).
文摘Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions,which is flourishing in soft robotics.However,the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods.In this study,we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency(PCE).The liquid crystalline elastomers doped with semiconductor bismuth compounds(Bi-LCE)used in this work exhibited large photothermal actuation with over 35%shrinkage in 5 s at high PCE state,which demonstrated little deformation at low PCE state.Furthermore,the material was capable of being reprogrammed up to 10 times,with only 20 min required for one PCE reversible switch.Based on this switchable PCE effect,the same Bi-LCE film displayed various shape changes through different programmable pattern.Additionally,a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter,cross-section configuration,and surface morphology,which was crucial for microfluidics field.Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics.
