| Title |
Hydrothermal liquefaction of spent coffee grounds followed by biocatalytic upgradation to produce biofuel: a circular economy approach |
| ID_Doc |
28582 |
| Authors |
Muller, LC; Pearson, J; Louw, J; Marx, S; Karmee, SK |
| Title |
Hydrothermal liquefaction of spent coffee grounds followed by biocatalytic upgradation to produce biofuel: a circular economy approach |
| Year |
2022 |
| Published |
Biofuels-Uk, 13.0, 6 |
| DOI |
10.1080/17597269.2021.1948757 |
| Abstract |
Hydrothermal liquefaction (HTL) of wet spent coffee grounds was performed in a batch reactor for bioenergy production. The effects of spent coffee grounds to water ratio, temperature and reactor volume occupation on product yield were investigated. A maximum 19.1 wt% bio-oil yield with HHV of 38.5 MJ/kg was obtained from wet spent coffee grounds. Subsequently, the bio-oil synthesized via hydrothermal liquefaction was upgraded biocatalytically to bring down the acid value and to convert the bio-oil into a higher quality liquid biofuel. During this process the fatty acids present in the bio-oil were converted into fatty acid methyl esters (biodiesel) using lipase. Novozyme-435 converted similar to 85% of fatty acids in the bio-oil into fatty acid methyl esters at 35 degrees C after 14 h, as determined by H-1 NMR. In addition, FTIR analysis confirmed the presence of fatty acid esters in the product. The acid number of the bio-oil decreased significantly after the enzymatic reaction. The results shows that lipase is an effective biocatalyst for crude bio-oil upgradation. |
| Author Keywords |
Hydrothermal liquefaction; spent coffee grounds; lipase; biorefinery; circular economy |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:000680817600001 |
| WoS Category |
Energy & Fuels |
| Research Area |
Energy & Fuels |
| PDF |
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