Extracting phycocyanin from spirulina and hydrothermal liquefaction of its residues to produce bio-crude oil

Extraction;Purification;Spirulina;Phycocyanin;Bio-crude oil;Hydrothermal liquefaction

Guan, Shaochen ; Schideman, Lance Charles, ; ,Martins, Marcio Arêdes ; Zhang ; Yuanhui

关键词: Extraction;    Purification;    Spirulina;    Phycocyanin;    Bio-crude oil;    Hydrothermal liquefaction;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/92665/GUAN-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Microalgae is a promising biofuel source with high photosynthetic efficiency, and it often contains high-value substances for nutritional, pharmaceutical and medical applications. In order to improve the economic viability of the spirulina utilization, this study investigated a cost competitive biotechnological process for C-phycocyanin (C-PC) extraction from spirulina platensis.The residual biomass after C-PC extraction was converted into bio-crude oil via hydrothermal liquefaction (HTL). The HTL bio-crude oil obtained from the original spirulina feedstock and the residual after the C-PC extraction were compared.A rapid and efficient process for extraction and purification of food-level C-PC from spirulina platensis was developed in this study. The process conditions include: 1) freeze the spirulina 3 hours to extract the crude protein; 2) add 80 g/L (w/v) activated carbon to the crude extract; 3) use a vacuum filter with a 0.22 μm pore size membrane to collect the extract; and 4) freeze dry the extract to get the C-PC powder. The yield of the C-PC production is 27% and the cost (exclude labor) for entire process is $26.1/kg. After C-PC extraction, there is still 63% dry biomass left which was used for conversion into bio-crude oil via HTL.The HTL bio-oil products distribution as well as their composition, reaction pathways and energy recovery via HTL were investigated. HTL was conducted at temperatures range from 260˚C to 300˚C at 0.7 MPa N2 initial pressures. The highest bio-crude oil yield of 38 % (based on dry volatile matter) was obtained at 300˚C. The highest higher heating value is 37.1 MJ/kg occurred at 300°C reaction temperature. Elemental analysis revealed that the decarboxylation and denitrification may be dominant from 260˚C to 300°C following repolymerization governing at higher temperature; TG analysis showed that approximately 75.4 % distilled bio-crude products were in the range of 200-550°C. These distillates can be further upgraded for transportation fuels.