Sulfated/Zr-containing mesoporous carbons: A promising nanostructured catalytic material

Abstract

In this work, we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia (SZr-SMC). The process of assembling P123, starch, zirconia, and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. SZr-SMC has a surface area of approximately 1300 m2/g, and a total pore volume of 0.94 cm3/g, composed mainly of mesoporous with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Ammonia thermodesorption studies indicated that, SZr-SMC retains 2.49 mmol/g of NH3 at very high temperature, exhibiting a strong acidity. According to the data collected by infrared spectroscopy (FTIR), of pyridine desorbed at various temperatures, the total number of acidic sites was 2.36 mmol/g, and the distribution in weak- medium, strong, and super acidic sites was determined. The activity in the methylation of aniline and isopropanol dehydration indicated that the acid sites are strong, and have not redox properties. A new and promising catalytic material based on mesoporous carbons modified with sulfated Zr is developed, which opens a wide range of acid-catalyzed reactions applied to industrial and medical processes.