Study on Biosorption of Heavy Metal Contaminated Wastewaters Integrated with Hydrothermal Liquefaction to Generate Biofuel

Document Type


Degree Name

Master of Science (MS)



Date of Award

Summer 2023


Industrial establishments released effluents possess heavy metals and these pose serious risks to the environment and society. To add more to this issue, drastic use of fossil fuels in the modern world would need to be addressed due to its environmental impacts and non-renewable nature. Governing and utilizing nonrenewable sources has become vital for most countries that pledged to scale down greenhouse gas emissions. Substituting biomass with fossil fuel resources to adhere to the sustainable development programs has been practiced for years now and is also widely accepted. Microalgae can thrive in industrial waste and other harmful environments. Its fast-growing nature and its ability to efficiently bind metal ions with the functional groups on the surface of their cell wall enables microalgae to be an ideal medium for cleaning up wastewater containing metals via biosorption. This study focused on biosorption of heavy metal rich wastewater using chlorella followed by hydrothermal liquefaction (HTL) process for biofuel production to provide a way to solve both environmental and energy issues in one shot. Three different brands of chlorella were used to investigate their biosorption capacities and kinetics toward Cu/Ni contaminated wastewater and to produce bio-oil via HTL. Starwest showed better results than the other two chlorella brands both for biosorption of Cu and or Ni and bio-oil production. A maximum bio-oil yield of 35.16wt% was obtained from the HTL of 0.5ppm Cu contaminated Starwest chlorella in 250-0-Air condition. Starwest also showed the highest weight change in the boiling point range of 200-300°C. Higher the metal concentration used in biosorption of Cu, higher the percentage of N heterocyclic compounds found in GCMS analysis of bio-oil.


Ben Jang

Subject Categories

Chemistry | Physical Sciences and Mathematics