Effect of Grain Size, Temperature and Catalyst Amount on Pyrolysis Products of Spirulina Platensis Residue (SPR)

Abstract

Spirulina platensis microalgae is one of the feedstocks used in the production of the third generation of biofuel. The extraction of its lipid for biodiesel leaves behind a residue, which can be treated by pyrolysis to create certain other value-added products. This paper discusses the effects of Spirulina platensis residue (SPR) with respect to grain size (0.105, 0.149 and 0.177 mm), temperature (300 to 600°C) and amount of catalyst (0, 10, 20 and 40 wt.%) on the characteristics of products (bio-oil, water phase, char and gas) obtained from pyrolysis in a fixed-bed reactor. The results of the study show that the higher the pyrolysis temperature, the higher the conversion. For the bio-oil product, the optimum temperature is 500°C, which produces a peak yield of 35.99 wt.%. The larger the grain size, the lower the bio-oil yield, gas water and gas, for all of the tested temperatures (300–600°C). The amount of catalyst and the pyrolysis temperature greatly influence the quality of bio-oil products, grouping them into the fractions of LPG (C ? 4), gasoline (C5–C11), biodiesel (C12–C18) and heavy naphtha (C ? 19). The tendency for LPG-Gasoline formation at optimum conditions, considering the use of a 10 wt.% catalyst at a temperature of 400–500°C, was reported.

Keywords

• Alumina silica
• Bio-oil pyrolysis
• Fixed-bed
• Spirulina platensis residue