Paper details

Title:

Production of a H₂ Rich Gas from Biodiesel Derived Glycerol by Catalytic Steam Reforming as a Solution to Improve Biodiesel Economy

Author(s):

Remón, J., Jarauta, C., Ruiz, J., Oliva, M., Garcia, L.

Document(s):

Abstract:

In the present work the catalytic steam reforming of biodiesel-derived glycerol has been studied as a possible solution to valorise this by-product towards a hydrogen rich gas. Specifically, the influence of the pH used in the purification step (5-7) has been studied aiming to select the best refining conditions for the posterior upgrading by catalytic steam reforming. Once the purification optimised, the steam reforming operating conditions: temperature (400-700 ºC), glycerol concentration (10-50 wt.%) and the W/mglycerol ratio (3-17 g catalyst min/ g glycerol) of this purified glycerol have been studied using a two level-three factor design of experiment with statistical analysis of the results. From the refining experiments, it was found that the pH had a significant influence during the purification step when acetic acid was used. The best refining results in terms of purity (85.25 . 0.79 wt.% of glycerol) and phase separation speed were achieved when a pH of 6 was used. From the reforming results, it was found that all the variables had a statistically significant influence on the reforming step. Depending on the operating conditions, the carbon conversion to gas, liquid and solid varied from 3 to 100%, 0 to 10% and 0-94%, respectively. These operating variables also had a significant influence on the composition of the gas phase. The gas phase was made up of a mixture of H2 (65-95 vol.%), CO2 (2-29 vol.%), CO (0-18 vol.%) and CH4 (0-5 vol.%). As a result of the optimization process, a possible optimum was found at a temperature of around 680 ºC, feeding a glycerol solution of a 37 wt.%. These operating conditions provide a carbon conversion to gas of a 95% and a gas with the following composition: 67 vol.% H2, 22 vol.% CO2, 11 vol.% CO and 1 vol.% CH4, minimizing the temperature and maximizing the amount of glycerol in the feed.

Keywords:

biodiesel, catalytic conversion, hydrogen

Topic:

Biomass Conversion Technologies for Intermediates, Liquid and Gaseous Fuels, Chemicals and Materials

Subtopic:

Biorefineries and chemicals production

Event:

22nd European Biomass Conference and Exhibition

Session:

3BV.3.26

Pages:

1086 - 1092

ISBN:

978-88-89407-52-3

Paper DOI:

10.5071/22ndEUBCE2014-3BV.3.26

Price:

FREE