Characterization and Performance Test of Sulfonated Activated Carbon as a Catalyst in the Levulinic Acid Production Process from Cellulose

The production levulinic acid from cellulose was investigated using active carbonas catalyst. This research conducted the characterize of activated carbon, sulfonated activatedcarbon, and nickel impregnation into sulfonated active carbon. The results showed that theacidity of the active carbon catalyst is 1233.046 μmol/g, while the Ni/sulfonated activatedcarbon had the highest catalyst acidity of 6106.512 μmol/g. In addition, the highest acidity ofthe sulfonated activated carbon catalyst was obtained at a sulfonation temperature variable of150℃ and a H2SO4 concentration of 10 N is 5108.332 μmol/g. At a sulfonation temperaturethat is too high, degradation of the -OH functional group occurs and can damage the porestructure of the active carbon. The results of FTIR analysis show that in the sulfonated activatedcarbon catalyst, the S-O, S=O, and C-S groups appear at wavelengths of 748-883 cm-1, 1148cm-1, and around 600 cm-1 respectively, which proves that the sulfonic acid group successfullyattached to the surface of the sulfonated carbon catalyst. Meanwhile in Ni/sulfonated activecarbon, the Ni2+ peak appears at a wavelength of 473 cm-1. XRD patterns of the three variables,indicating that sulfonation does not affect the carbon microstructure. The appearance of a newpeak at 43° indicates the presence of NiO species in Ni/sulfonated active carbon and the sharperpeaks in Ni/sulfonated active carbon indicate that there has been a change in the amorphousarea to crystalline, which proves that Ni metal is not only attached to the surface but has enteredthe active carbon structure. Catalyst performance test show that hydrothermal cellulose withoutcatalyst produces a cellulose conversion of 12% while active carbon catalyst produces acellulose conversion of 20%. The results of the catalyst performance test also show thathydrothermal cellulose using sulfonated activated carbon produces a conversion of 30% due tothe presence of -COOH, -OH, and -SO3H functional groups which have the power to adsorbcellulose so that it is efficient for the cellulose hydrolysis reaction. The highest celluloseconversion of 42% was achieved when using Ni/ sulfonated active carbon due to the presenceof Ni which bound to the sulfonate groups enhanced the acidity and catalytic activity.