Extracting Biofuels from Spent Coffee Grounds and Waste Pine Needles

Friday, February 17, 2017
Exhibit Hall (Hynes Convention Center)
Sneha Sharma, Holmdel High School, HOLMDEL, NJ
Each year, 33 million Christmas trees and 29,000 tons of spent coffee grounds (SCG) are disposed of. Yet, these waste products have the potential to fill an urgent global need: a need for alternative fuel sources. This research evaluates the viability and efficacy of extracting biofuels from spent coffee grounds (SCG) and waste pine needles (WPN). Extraction was conducted with a Soxhlet extractor over 20 trials; each run was 2 hours long. The 20 trials were grouped based on pairing of solvent and source: 5 trials with SCG and isopropanol, 5 trials with SCG and hexane, 5 trials with WPN and isopropanol, 5 trials with WPN and hexane. Following the extraction, the products were distilled, trans-esterified and analyzed. The analysis included calculation of heat of combustion (kJ/g), biofuel yield (%) and density (g/ml) of each resulting biofuel sample. Conclusively, the study determined that: (1) viable biofuels can be successfully extracted from SCG and WPN, (2) Isopropanol is a more effective extracting solvent than hexane, (3) WPNs provide the greatest biofuel yield when extracted with isopropanol.