Study On The Catalytic Degradation Of Pyrolysis Liquid Products Of Pine By Diatomite Complex

Effective degradation of biomass tar is the key link of biomass pyrolysis gasification technology,and the use of catalytic technology to degrade biomass pyrolysis tar is one of the current research hotspots in biomass pyrolysis gasification.Choosing a cheap and efficient catalyst is of great value to reduce the cost of catalysis.Diatomite has a well-developed pore structure,which results in abundant active sites and strong adsorption characteristics.In this paper,the use of diatomite as a catalyst for the catalytic pyrolysis of pine wood,and the liquid phase product of pine pyrolysis as the research object of catalytic degradation,to explore the degradation of pine wood pyrolysis liquid product by diatomite?DE?composite law.Experimental study on the degradation characteristics of pine pyrolysis liquid products under three composite catalysts of diatomite,diatomite-bentonite and diatomite-bentonite-Fe,hereinafter referred to as DE,DE/B,DE/B?Fe?.In order to get the degradation law and characteristics of diatomite compound to biomass pyrolysis liquid products.The research results are as follows:?1?In order to optimize the shape of the diatomite?DE?test material,three materials with different channels were made,which were denoted as DE-5,DE-3 and DE-1.The pyrolysis test of pine wood pellets was carried out on a self-made pyrolysis reaction platform.The test results are as follows:The addition of DE material has a significant degradation effect on the treatment of liquid phase products in the pyrolysis volatiles.The liquid phase yield after adding the material DE decreased by 13.01%compared with None.But different shapes of DE materials have different treatment effects on pyrolysis volatiles.The effect of pyrolysis volatiles treatment is as follows:DE-3>DE-5>DE-1.At 850°C,the yield of DE-3 pyrolysis liquid reached a minimum of 20.87%,reduced by 3.76%and 5.11%compared to DE-5 and DE-1.?2?In the test,the strength of diatomite?DE?was found to be weak.After high-temperature pyrolysis tests,crushing often occurred and affected its use.In response to this,adding diatomite-bentonite composite material on the basis of the material DE to add bentonite,denoted as B/DE,and explore its characteristics and impact on pyrolysis volatiles.In the test,it is found that the addition of bentonite is beneficial to the increase of the strength of the DE material,and the strength increases with the increase of the proportion of bentonite added.Through the pyrolysis test,it was found that the addition of bentonite did not inhibit the catalytic degradation of diatomite on the pyrolysis liquid phase products.?3?Add Fe₂O₃ powder on the basis of material 4-B/DE-3.Pyrolysis test on pine sawdust particles found,the addition of Fe₂O₃ powder promotes the catalytic cracking of pyrolysis oil,resulting in a decrease in the liquid phase yield after pyrolysis.The effect is best at 800°C.At this time,the liquid phase yield is 18.96%,which is 3.3%and 2.61%lower than DE-3 and 4-B/DE-3.