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First, the specific components of each catalyst combination shall be listed according to Annex I , A series of parallel controlled experiments were selected according to the principle of single variable , Comparative analysis of experimental data ！

（1）Co Load capacity

Parallel control experimental group ：A1,A2,A4,A6

Loading ratio 200mg：200mg

Ethanol concentration 1.68ml/min

①Co Load capacity —— Ethanol conversion

At a temperature of 275℃ to 325℃ Between time ,2wt% Co The load increased the ethanol conversion significantly ; When the temperature is less than 250 Degrees Celsius or greater 350℃ when ,5wt% Co The increase of load on ethanol conversion is more significant .

Sum up ,Co The increase of load is beneficial to the overall improvement of ethanol conversion , but Co Excessive load may lead to poor conversion efficiency of ethanol in a certain medium temperature range .

②Co Load capacity ——C4 Olefin selectivity

stay 250℃ to 350℃ Within the reaction temperature range , There is one. Co Optimum load , bring C4 Olefin selectivity is optimal . According to the experimental data ,Co The optimum load of is 1wt% In the neighborhood of .Co The load exceeds or falls below the optimum load , Will make C4 Decrease in olefin selectivity .

Sum up ,Co There is an actual optimal value of the load （ near 1wt%）, bring C4 Olefin selectivity is maximized .

（2）Co/SiO2 and HAP Loading ratio

Parallel control experimental group ：A1,A12,A13,A14

Co Load capacity 1wt%

Ethanol concentration 1.68ml/min

①Co/SiO2 and HAP Loading ratio —— Ethanol conversion

When the total charge mass is the same ,Co/SiO2 and HAP Loading ratio The smaller the ratio of , The more significant the improvement of ethanol conversion ; When Co/SiO2 and HAP Loading ratio When the ratio is the same , The greater the total mass of the charge , The ethanol conversion rate increased significantly in the medium temperature range , However, the improvement effect in the high-temperature range is not as good as the catalyst combination with small total charge mass .

Sum up , smaller Co/SiO2 and HAP The loading ratio can significantly improve the conversion of ethanol . For the medium temperature range , The combination of catalyst can greatly improve the total conversion of ethanol ; For high temperature range , The catalyst combination with smaller total charge mass has more advantages .

②Co/SiO2 and HAP Loading ratio ——C4 Olefin selectivity

When the total charge mass is the same ,Co/SiO2 and HAP Loading ratio There is an optimal ratio , bring C4 The improvement of olefin selectivity is optimal , It can be seen from the experimental data that the optimum ratio is 1：1 In the neighborhood of ; When Co/SiO2 and HAP Loading ratio When the ratio is the same , The greater the total mass of the charge ,C4 The improvement of olefin selectivity is very significant .

Sum up , about C4 The most important factor affecting the selectivity of olefins is Co/SiO2 and HAP The total mass of the charge . The greater the total mass of the charge ,C4 The greater the olefin selectivity . also Co/SiO2 and HAP The loading ratio may be close to 1： 1 The best ratio , bring C4 Olefin selectivity is maximized .

（3） Ethanol concentration

Parallel control experimental group ：A7,A8,A9

Co Load capacity 1wt%

Loading ratio 50mg：50mg

① Ethanol concentration —— Ethanol conversion

According to the principle of chemical equilibrium , The increase of reactant concentration will make the equilibrium move forward , But the conversion of reactants will decrease , The results of the experiment are consistent with them , The correctness of the principle of chemical equilibrium is verified . That is, when the ethanol concentration increases , The conversion rate of ethanol decreased significantly .

Sum up , The conversion rate decreased significantly with the increase of ethanol concentration .

② Ethanol concentration ——C4 Olefin selectivity

It can be seen from the experimental data that , High concentrations of ethanol will increase C4 Selectivity of olefins . It is reasonable to guess that the increase of ethanol may inhibit the occurrence of side effects , The proportion probability of main reaction increases , Thus making C4 Increased selectivity of olefins .

Sum up , High concentration of ethanol can significantly improve C4 Selectivity of olefins .

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