Synthesis Of Microporous Carbon Spheres And Boron Nitride And Their Applications In The Dehydrogenation Of Propane

The rapid development of polypropylene,polyacrylonitrile,acrylic aldehyde and acrylic acid has greatly promoted the rapid growth of the global demand for propylene.The efficient conversion of propylene from low carbon alkane can not only accelerate the development and utilization of fuel gas,but also reduce the excessive dependence of chemical industry on petroleum resources.As a traditional non-metallic catalyst,carbon material has important application value in catalysis field because of its unique composition and structure,high specific surface area,well-organized pore size distribution and high thermodynamic stability,which is the best substitute for metal catalyst.Numerous literature shows that,the non-metal catalyst carbon catalyst,the quincarbonyl C=O on the O^2-and carbon surface of oxygen species is the active site of alkanes dehydrogenation to prepare olefins,while the electrophilic oxygen species O^2-and O₂^2-are the source of the excessive oxidation of alkanes.In this paper,the microporous carbon materials and nonmetallic boron nitride materials were modified and applied to propane dehydrogenation reaction.?1?With F127 as a template and sodium hydroxide as the catalyst,the microporous carbon spheres were obtained by the polymerization of phenol and formaldehyde under the condition of low temperature and hydrothermal conditions.The micropore carbon was modified with three different phosphorus sources.In the modified carbon catalyst,the microporous carbon with the modification of triethyl phosphate has the best catalytic active propane conversion rate of 32%,propylene selection is 87%,and the catalytic activity of micro-pore carbon modified by phosphoric acid has decreased compared with that of micro-pore carbon.?2?Hexagonal boron nitride?h-BN?is synthesized by means of high-temperature cracking using melamine and boric acid as raw materials.The synthesized materials are mesoporous materials,and the different roasting temperature causes the material to have unordered porous block and lamellar structure.The specific surface area can be up to 210 m²/g with a minimum of 42 m²/g.When h-BN was used for propane oxidation dehydrogenation,it showed good catalytic activity and stability.In the reaction time of 7h,the highest yield of propylene was27%.When the conversion rate of propane was 25%,the selectivity of propylene was77%.This provides a basis for propane oxidation dehydrogenation.?3?The introduction of carbon into the skeleton of boron nitride can improve its catalytic activity.The introduction of carbon into the skeleton of boron nitride can improve its catalytic activity.This kind of ternary material shows good catalytic synergism for propane oxidation dehydrogenation.In the 7h reaction time,the propylene has the highest yield of 31%,and the rate of conversion of propane is up to55%,but it's only 60%selectivity.It means that the mixture of carbon is capable of synergy with boron boron,increasing its ability to dehydrohydrogen from propane.