The reliance on fossil fuels contributes significantly to CO 2 emissions, leading to environmental degradation and energy insecurity. Renewable energy sources, such as microalgal and cyanobacterial biomass, offer a sustainable alternative. This study investigates the ex-situ catalytic pyrolysis of Spirulina (Arthrospira) platensis (SP) using a fixed-bed reactor to evaluate the effects of activated carbon (AC), ginger ( Zingiber officinale , ZO), and NaOH as catalysts on product distribution and bio-oil properties. The resulting bio-oil was characterized based on density, viscosity, gross calorific value (GCV), functional groups, and compound composition. The catalytic mixture of the ACZO:NaOH(3:1) ratio yielded the highest bio-oil production (13.2%), with the highest hydrocarbon content of 91.98%, while also exhibiting the highest density (1032 kg/m 3 ) and viscosity (9.755 × 10 −5 m 2 /s). In contrast, the ACZO:NaOH (1:3) ratio produced the highest GCV bio-oil (37.547 MJ/kg) and the highest gas yield (64.25%). FTIR analysis revealed that bio-oil from the 1:3 ratio contained fewer O H functional groups, indicating a lower oxygenate content and supporting the higher GCV findings. These results highlight the potential of combining AC, ZO, and NaOH to optimize bio-oil quality and gas production from SP pyrolysis, offering valuable insights for future biomass-to-energy conversion processes. • Zingiber officinale (ZO) and NaOH act as effective hydrogen donors in pyrolysis. • The combined ACZO:NaOH enhances hydrodeoxygenation (HDO) reactions. • ACZO:NaOH(1:3) yields the highest bio-oil GCV with reduced O H band. • Bio-oil density and viscosity are influenced by N- and S-substituted aromatics. • NaOH promotes cracking and decarboxylation, forming more hydrocarbon species.
Sukarni et al. (Fri,) studied this question.