The Bio-ethylene Formation by Catalytic Dehydration of Bioethanol for a Pine Sawdust Biorefinery.

MENDIETA CAROLINA; SANTORI GERARDO; FELISSIA FERNANDO; AREA MARIA CRISTINA

Buenos Aires

Congreso; WCCE11 World Congress of Chemical Engineering; 2023

The objective of this work was to evaluate the temperature and catalyst dosage to achieve the highest ethanol conversion and ethylene selectivity using commercial ethanol and 2G bioethanol through commercial catalysts. The stages to produce ethylene are pretreatment, enzymatic hydrolysis, fermentation, and dehydration. The pulp had the following chemical composition: 80.18% Glucans, 7.20% Xylans, 0.29% Galactans, 8.40% Mannans, and 3.67% Lignin [1]. The commercial catalysts used for the dehydration process were ϒ-Al2O3, ZSM-5 zeolites (Si O2 /Al2O3) 23 molar, YCBV-500 (SiO2/Al203) 5.2 molar, and protonated zeolites with a calcination treatment (HZSM-5 and HYCBV-500) at 550ºC, 2h, and 2ºC/min. The catalyst dosages were 400mg, 200 mg, and 100 mg.Results in the dehydration process with commercial ethanol were 98.46% ethanol conversion and 100% ethylene selectivity with ϒ-Al2O3 at 395ºC, 97.05% ethanol conversion and 100% ethylene selectivity with ZSM-5 at 398ºC, 96.62% ethanol, and 100% ethylene selectivity with HZSM-5 at 286ºC and 97.7% conversion to ethanol and 100% ethylene selectivity with HYCBV-500 at 357ºC. For the dehydration of 2G bioethanol, the protonated catalysts (HZSM-5 and HYCBV-500) were selected since they achieved the highest ethanol conversion and ethylene selectivity at lower temperatures (94.58% ethanol conversion and 100% ethylene selectivity at 321ºC with HZSM-5 catalyst and 85.49% conversion and 100% ethylene selectivity at 334ºC with HYCBV-500. Regarding the catalyst dosage (400 mg and 200 mg), the ethanol conversion and the ethylene selectivity were 98.82% and 100% at 310°C, respectively. However, with 100 mg, ethanol conversion and ethylene selectivity decreased (62.66% ethanol conversion and 82.63% ethylene selectivity at 311°C).