Table 2.
Synthesis of levulinic acid from smoked cigarette filters.
| entry | Raw material (weight) | Catalyst (M)a | T (°C) | Time (h) | LA yields | Ref | |
|---|---|---|---|---|---|---|---|
| (%)b | (% filter wt)c | ||||||
| 1 | Washed filter (251.15 mg) | H3PO4 (1.5) | 200 | 2 | 33 | 15.30 | This work |
| 2 | Unwashed filter (251.29 mg) | H3PO4 (1.5) | 200 | 2 | 31 | 14.31 | This work |
| 3 | Filter-paper cellulosed | H3PO4 (0.15) | 200 | 2 | – | 40 | 13 |
| 4 | Paper sludge | H2SO4 (0.47) | 200 | 1 | 26.5 | 15.1 | 14 |
| 5 | Paper sludge | HCl (0.47) | 200 | 1 | 55.1 | 31.4 | 14 |
Procedure as reported in experimental section.
aVolume = 15 mL.
bReferred to theoretical amount of LA (see “Materials and methods” section).
cReferred to the filter weight14. All yield values were obtained based on three replicate experiments (SD ± 2.0).
dThe pretreatment temperature and time were set to 50 °C and 24 h.