Carbon catalysts from pine cones - Synthesis and testing of their activities

The work presents research on the synthesis of carbon catalysts from pine cones and their application in the oxidation of alpha-pinene. The preparation of carbon catalysts involved chemical activation with an aqueous potassium hydroxide solution and carbonization of the obtained precursor. The pine cones carbonization was performed for 1h at the temperatures range from 700 degrees to 1000 degrees C in an inert gas atmosphere (N-2). Characterizations of the activated carbons were performed with the following instrumental analyses: XRD, SEM, and XPS. No solvent was used in the oxidation studies, and molecular oxygen was the oxidizing agent. The effects of three parameters - temperature, amount of the carbon catalyst, and reaction time - on the values of conversion of alpha-pinene, as well as the product selectivities, were investigated. It was shown that it is most advantageous to perform the oxidation of alpha-pinene at 100 degrees C for 1h with the PC_850 catalyst (so-named for the temperature of its carbonization process, 850 degrees C), whose content in the reaction mixture is 0.5 wt%. Under these conditions, the conversion of alpha-pinene amounted to 41 mol%. Moreover, the selectivities of the three main products were: alpha-pinene oxide (28 mol%), verbenol (16 mol%), and verbenone (13 mol%). In addition to these products, other valuable compounds, such as campholenic aldehyde, pinocarveol, myrtenal, myrtenol, carveol, carvone, and pinanediol were also produced.

Automated summary

This work presents the synthesis of carbon catalysts from pine cones and their application in the oxidation of alpha-pinene. The study investigates the effects of temperature, carbon catalyst amount, and reaction time on the conversion and selectivities of alpha-pinene. The results show that under specific conditions, the oxidation of alpha-pinene using the PC_850 catalyst can achieve high conversion and selectivity to desired products.