Preparation Of Biopolymer Carbon Aerogel And Its Catalytic Performance For AP Decomposition

Ammonium perchlorate(AP)is the most common oxidant in the composite solid propellant of solid fuel rockets,accounting for 60%-90%of the total propellant.The performance of composite solid propellant,especially the burning rate,depends to a large extent on the reaction rate,activation energy and pyrolysis temperature of AP.Adding a combustion catalyst is an effective way to increase the combustion rate of the propellant,which can reduce the pyrolysis peak temperature and activation energy of AP,thereby improving the combustion performance of the AP-containing propellant.Commonly used combustion catalysts include simple metal elements and metal oxides,which generally have shortcomings such as small specific surface area and easy agglomeration.Therefore,this paper proposes to develop a new type of combustion catalyst-carbon aerogel to study its catalytic effect on the thermal decomposition of AP.The main work is as follows:(1)Using sodium alginate as raw material,the sodium alginate-Cu new biomass carbon aerogel is prepared by cross-linking method,freeze-drying method and one-step carbonization method,using XRD,FI-IR,SEM,TEM,XPS and BET characterizes its structure and morphology.The results show that the prepared carbon aerogel has a layered porous structure,a large specific surface area,and can effectively disperse metal element and metal oxides.The effect of the prepared catalyst on the thermal decomposition performance of AP was studied using differential thermal analysis technology.The results show that under the condition of 10K/min heating rate,the prepared carbon aerogel reduces the peak temperature of AP pyrolysis by 94?,and the apparent activation energy of pyrolysis is reduced by 45.7 k J/mol,and its mechanism of action is discussed.(2)Using sodium alginate as the raw material,the sodium alginate-Co new biomass carbon aerogel was prepared by cross-linking method,freeze-drying method and one-step carbonization method.The effect of different carbonization temperature and catalyst content on carbon aerogel was studied.The morphology,specific surface area and influence on the catalytic performance of AP thermal decomposition.The results show that the catalytic performance of Co-alginate-based carbon aerogel-800 on the thermal decomposition of AP is better than that of Co-alginate-based aerogel-700.When the additive amount is 10 wt%,the catalytic effect is the best,which can reduce the peak temperature of AP's pyrolysis by 121?and reduce the apparent activation energy of pyrolysis by 18.9 k J/mol.(3)Using NaOH and acidified NaClO₂ as solvents,extract natural cellulose from waste palm bamboo leaves,and then mix it with ZIF-67.A new type of Co-brown bamboo-based biomass carbon aerogel was prepared by freeze-drying and one-step carbonization.The structure and morphology characterization results show that the prepared carbon aerogel has a 3D network structure,and ZIF-67 is uniformly distributed in the cellulose after carbonization,showing a rough and porous polyhedral shape.The DTA test method was used to study the effect of Co-brown bamboo-based biomass carbon aerogel on the catalytic performance of AP thermal decomposition.The results show that the addition of 5 wt%Co-brown bamboo-based biomass carbon aerogel can reduce the pyrolysis peak temperature of AP by 115?and the apparent activation energy of pyrolysis by 124.8 k J/mol.The above research results show that the three biomass carbon aerogel catalysts prepared have good catalytic effects on the thermal decomposition of AP,and they are expected to be used as combustion catalysts in AP-containing composite solid rocket propellants and have good application prospects.