Abstract
Acetaldehyde has been historically synthesized from ethanol via oxidation. However, since the 1960s, the cost of feedstock and conversion process has gradually driven manufacturers to prefer the liquid-phase oxidation of ethylene. However, the aggravation of the effects of the climate crisis demands a shift from fossil feedstocks to renewable feedstocks to reduce society’s CO2 footprint. Moreover, sugarcane ethanol production is a more mature process nowadays, delivering a low-cost renewable chemical. Bearing all this in mind, this work analyzes the viability of the production of acetaldehyde via oxidation of sugarcane ethanol. The key idea is to integrate the process into a sugarcane biorefinery to take advantage of the surplus energy of optimized distilleries to provide renewable energy for acetaldehyde production. The oxidation process of ethanol to acetaldehyde in the gas phase was simulated using literature data. Process data for the remaining sections of the sugarcane biorefinery were based on literature data as well. Based on equipment sizing and processing capacity, a cash flow analysis was performed to determine the best operating conditions for acetaldehyde production via ethanol oxidation. Results have shown that the conversion of ethanol to acetaldehyde using this process is competitive and can increase the earnings of the biorefinery. A life cycle assessment was performed as well to compare the carbon intensity of acetaldehyde produced from ethanol to the carbon intensity of acetaldehyde produced via direct oxidation of ethylene, showing a reduction of 85%. Results demonstrate that the oxidation of ethanol represents a renewable alternative with economic potential when integrated into a sugarcane biorefinery.
