**3.4 Pyrolysis of α-cellulose (bio-oil)**

Pyrolysis of α-cellulose in the form of a white powder produces a liquid product that has physical characteristics, dark brown, thick and has a strong odor. In addition, the oil resulting from α-cellulose pyrolysis can easily change color when left to stand at room temperature and open conditions. This change is possible due to the oxidation process. Experiment of [5] explained that bio-oil obtained from biomass pyrolysis is a multi-component mixture that has high acidity, high water content and is unstable in storage. The instability characteristic of the pyrolysis bio-oil is indicated by the easy color change of the α-cellulose pyrolysis bio-oil.

The liquid product resulting from α-cellulose pyrolysis was analyzed by GC–MS to determine the approximate compounds contained in the liquid product using data detected by MS after the liquid components were separated by the GC method. In addition, analysis of the content of the liquid product from α-cellulose pyrolysis by GC–MS is useful for knowing the main components of the liquid product from α-cellulose pyrolysis itself using area data from GC results. The results of the analysis of the liquid product content of α-cellulose pyrolysis are used as a reference in assessing the success of the hydrotreating process using a catalyst that has been synthesized. The conversion value of α-cellulose pyrolysis in this study was around 40–50% and the results of α-cellulose pyrolysis are shown in **Table 7**.

**Table 7** shows that the liquid product resulting from α-cellulose is pyrolyzed containing furan, ketone, aldehyde, and carboxylic acid group compounds. Based on regional data, the five main components of the liquid product resulting from α-cellulose pyrolysis are 2-furancarboxaldehyde (21.21%), 1-hydroxy-2-propanone (20.96%), formic acid (9.15%), acetic acid (7.66%) and ethanal (7.27%). These results are the same as those of researchers [5] in their research report where the


#### **Table 7.**

*Analysis results of the main product of a-cellulose by GC–MS.*

liquid products from the hydrolyzed α-cellulose contained the main components in the form of furan compounds, ketones, carboxylic acids and aldehydes.
