Title:
Conversion of Biomass Syngas to Higher Alcohols: from Lab Scale Experiments to Plant Design
Author(s):
Atsonios, K., Christodoulou, C., Liakakou, E., Koytsoumpa, E.I., Heracleous, E., Panopoulos, K.D., Lemonidou, A.A.
Document(s):
Paper
Abstract:
The catalytic conversion of synthesis gas originating from biomass produces ethanol, plus C3-C4 alcohols that could be used directly as fuels or as fuel additives for octane or cetane enhancement. The reaction has been studied over a wide range of catalytic materials, but has been limited up-to-date by low yields and poor catalyst selectivity. Of paramount importance for the efficient production of higher alcohols from biomass is the effective coupling of the biomass gasification and gas cleaning parts with the subsequent biosyngas synthesis to alcohols. The present paper presents first attempts for analytical process modeling of high pressure gasification and synthesis from biomass of diverse feedstock for synthesizing 2nd generation fuels and chemicals, such as higher alcohols, performed with ASPENplusTM software. In a first step of the work, a thermodynamic study was conducted with the objective to determine the thermodynamic limitations of the processes and to select the schemes / operating conditions that favor the formation of higher alcohols. The results showed that the hydrogenation of CO to higher alcohols is favoured by high pressures, low temperatures and low H2/CO ratio. The same trend was observed in CO hydrogenation over a synthesized K-promoted CuZnAl catalyst, at experiments performed on a high-pressure small scale bench test unit. At a second step, the process was simulated with the basis of the experimental results of the Cu45/Zn45/Al10-K0.5 catalyst at 300°C and 40bar. At these conditions, the material exhibits satisfactory selectivity and good once-through higher alcohols yield equal to 36 g C2+alcohols/kgcat/h. The analysis includes an investigation of gas cleaning pathways and their effect on total process efficiency. Moreover, the effect of methanol separation and recycling to the synthesis reactor on the higher alcohols yield was addressed.
Keywords:
biomass gasification, catalyst, ASPEN Plus, Eurobioref, higher alcohols synthesis
Topic:
R&D on Processes for Solid, Liquid and Gaseous Fuels from Biomass
Subtopic:
Biofuel production from synthesis gas
Event:
20th European Biomass Conference and Exhibition
Session:
3DV.1.68
Pages:
1705 - 1708
ISBN:
978-88-89407-54-7
Paper DOI:
10.5071/20thEUBCE2012-3DV.1.68
Price:
FREE
