Analytical study on pyrolyzed products of Desmodesmus sp.cultivated in BG11

Pyrolysis-Gas Chromatography-Mass Spectrometry(Py-GC/MS)was adopted to determine the changes in component of BG11-cultivated Desmodesmus sp.(BG11/8-10)pyrolyzed products at different temperatures(300℃-800℃).The results of analysis on a series of total ions chromatogram(TIC)showed that pyrolyzed products of BG11/8-10 at different temperature mainly included aliphatic hydrocarbons,nitrogen compounds,aromatic hydrocarbons,fatty acids,ketones,alcohols,aldehydes and furan compounds.Compared to the bio-oil(42.36%)generated by pyrolysis at 700℃,the relative content of bio-oil generated at 800℃was the highest up to 56.96%.However,higher temperature could easily cause the generation of large quantities of such pollutants as nitrogen compounds and polycyclic aromatic hydrocarbons(PAHs).Therefore,based on lower pollutant discharge and higher bio-oil yield,the optimal pyrolysis temperature of BG11/8-10 was around 700℃.

Thermal cracking products and bio-oil production from microalgae Desmodesmus sp.

Qualitative and quantitative analyses of thermal cracking products from Desmodesmus sp.were performed based on pyrolysis-gas chromatography-mass spectrometry(Py-GC/MS)at different temperature regimes(350℃-750℃).After further analysis of a series of total ions chromatogram(TIC)and summarized,thermal cracking products of Desmodesmus sp.at different temperature regimes can be obtained,which mainly comprised of aliphatic hydrocarbons,nitrogen compounds,aromatic hydrocarbons,fatty acids,ketones,alcohols,aldehydes and furan compounds.Compared to bio-oil production at 650℃(32.07%),Desmodesmus sp.pyrolyzed at 750℃could produce the highest bio-oil content of 42.25%.However,higher temperature could lead to the formation of contaminants(nitrogen compounds and PAHs)more easily.Therefore,considering the higher content of bio-oil conversion and less pollutants generation,the optimum temperature for Desmodesmus sp.thermal cracking conversion was about 650℃.