Call: +34 974 239 320
Email: dalvira@unizar.es
Address: Escuela Politécnica Superior, Crta de Cuarte, s/n. E-22071 Huesca – Spain
ABOUT ME
Research Interests
- Producing biomass-derived chars by pyrolysis of agricultural wastes.
- Developing advanced carbon materials for thermal, catalytic and electrochemical applications.
- Activation and doping of engineered carbons as anodes for sodium-ion batteries.
Projects
- MEDWASTE —Mediterranean Agricultural Wastes: Environmentally Sustainable Resource for an Innovative Renewable Energy Technology (PCIN-2017-048)
- BIOCARB-ion —Engineered biochar-derived carbons as anodes for sodium- and potassium-ion batteries (PID2019-107737RB-I00)
PUBLICATIONS
2021
Manyà, Joan Josep; Alvira, Darío; Videgain, María; Duman, Gozde; Yanik, Jale
Assessing the Importance of Pyrolysis Process Conditions and Feedstock Type on the Combustion Performance of Agricultural-Residue-Derived Chars Journal Article
In: Energy & Fuels, 2021.
@article{Manya2021,
title = {Assessing the Importance of Pyrolysis Process Conditions and Feedstock Type on the Combustion Performance of Agricultural-Residue-Derived Chars},
author = {Joan Josep Manyà and Darío Alvira and María Videgain and Gozde Duman and Jale Yanik},
url = {https://dx.doi.org/10.1021/acs.energyfuels.0c04180},
doi = {10.1021/acs.energyfuels.0c04180},
year = {2021},
date = {2021-01-01},
journal = {Energy & Fuels},
publisher = {American Chemical Society},
abstract = {The combustion performance of chars derived from vine shoots, wheat straw, and corn stover was investigated to assess the influence of both the biomass precursor and pyrolysis operating conditions. Chars were produced through slow pyrolysis at different peak temperatures (350 and 500 °C), pressures (0.1 and 0.5 MPa), and residence times of the vapor phase (50 and 150 s). From the thermogravimetric curves obtained under air, the combustion performance index (S) was calculated for each char. Apparent kinetics were also estimated using the Coats−Redfern method and assuming an F3/2 reaction model. Results show that the combustion patterns of chars were more influenced by the type of feedstock than by the pyrolysis conditions. Corn stover appeared to be the most interesting feedstock in order to produce chars with tuned reactivity. Results from partial least-squares (PLS) regression revealed that the most important factors affecting S were the contents of potassium (negative effect) and cellulose (positive effect) in the original biomass.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The combustion performance of chars derived from vine shoots, wheat straw, and corn stover was investigated to assess the influence of both the biomass precursor and pyrolysis operating conditions. Chars were produced through slow pyrolysis at different peak temperatures (350 and 500 °C), pressures (0.1 and 0.5 MPa), and residence times of the vapor phase (50 and 150 s). From the thermogravimetric curves obtained under air, the combustion performance index (S) was calculated for each char. Apparent kinetics were also estimated using the Coats−Redfern method and assuming an F3/2 reaction model. Results show that the combustion patterns of chars were more influenced by the type of feedstock than by the pyrolysis conditions. Corn stover appeared to be the most interesting feedstock in order to produce chars with tuned reactivity. Results from partial least-squares (PLS) regression revealed that the most important factors affecting S were the contents of potassium (negative effect) and cellulose (positive effect) in the original biomass.
2019
Stasi, Christian Di; Alvira, Darío; Greco, Gianluca; González, Belén; Manyà, Joan Josep
Physically activated wheat straw-derived biochar for biomass pyrolysis vapors upgrading with high resistance against coke deactivation Journal Article
In: Fuel, vol. 255, pp. 115807, 2019, ISSN: 00162361.
@article{DiStasi2019,
title = {Physically activated wheat straw-derived biochar for biomass pyrolysis vapors upgrading with high resistance against coke deactivation},
author = {Christian Di Stasi and Darío Alvira and Gianluca Greco and Belén González and Joan Josep Manyà},
doi = {10.1016/j.fuel.2019.115807},
issn = {00162361},
year = {2019},
date = {2019-11-01},
journal = {Fuel},
volume = {255},
pages = {115807},
publisher = {Elsevier Ltd},
abstract = {Wheat straw-derived biochars (produced through slow pyrolysis at 500 °C and 0.1 MPa) were physically (with CO2) and chemically (with K2CO3) activated to assess their performance as renewable and low-cost catalysts for biomass pyrolysis vapors upgrading. Preliminary cracking experiments, which were carried out at 700 °C using a mixture of four representative model compounds, revealed a clear correlation between the volume of micropores of the catalyst and the total gas production, suggesting that physical activation up to a degree of burn-off of 40% was the most interesting activation route. Next, steam reforming experiments were conducted using the most microporous material to analyze the effect of both the bed temperature and gas hourly space velocity (GHSV) on the total gas production. The results showed a strong dependence between the bed temperature and the total gas production, with the best result obtained at the highest temperature (750 °C). On the other hand, the change in GHSV led to minor changes in the total gas yield, with a maximum achieved at 14500 h−1. Under the best operating conditions deduced in the previous stages, the addition of CO2 into the feed gas stream (partial pressure of 20 kPa) resulted in a total gas production of 98% with a H2/CO molar ratio of 2.16. This good result, which was also observed during the upgrading of the aqueous phase of a real biomass pyrolysis oil, was ascribed to the relatively high coke gasification rate, which refresh the active surface area preventing deactivation by coke deposition.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wheat straw-derived biochars (produced through slow pyrolysis at 500 °C and 0.1 MPa) were physically (with CO2) and chemically (with K2CO3) activated to assess their performance as renewable and low-cost catalysts for biomass pyrolysis vapors upgrading. Preliminary cracking experiments, which were carried out at 700 °C using a mixture of four representative model compounds, revealed a clear correlation between the volume of micropores of the catalyst and the total gas production, suggesting that physical activation up to a degree of burn-off of 40% was the most interesting activation route. Next, steam reforming experiments were conducted using the most microporous material to analyze the effect of both the bed temperature and gas hourly space velocity (GHSV) on the total gas production. The results showed a strong dependence between the bed temperature and the total gas production, with the best result obtained at the highest temperature (750 °C). On the other hand, the change in GHSV led to minor changes in the total gas yield, with a maximum achieved at 14500 h−1. Under the best operating conditions deduced in the previous stages, the addition of CO2 into the feed gas stream (partial pressure of 20 kPa) resulted in a total gas production of 98% with a H2/CO molar ratio of 2.16. This good result, which was also observed during the upgrading of the aqueous phase of a real biomass pyrolysis oil, was ascribed to the relatively high coke gasification rate, which refresh the active surface area preventing deactivation by coke deposition.
2016
Manyà, Joan Josep; Alvira, Darío; Azuara, Manuel; Bernin, Diana; Hedin, Niklas
Effects of Pressure and the Addition of a Rejected Material from Municipal Waste Composting on the Pyrolysis of Two-Phase Olive Mill Waste Journal Article
In: Energy and Fuels, vol. 30, no. 10, pp. 8055–8064, 2016, ISSN: 15205029.
@article{Manya2016,
title = {Effects of Pressure and the Addition of a Rejected Material from Municipal Waste Composting on the Pyrolysis of Two-Phase Olive Mill Waste},
author = {Joan Josep Manyà and Darío Alvira and Manuel Azuara and Diana Bernin and Niklas Hedin},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/acs.energyfuels.6b01579},
issn = {15205029},
year = {2016},
date = {2016-10-01},
journal = {Energy and Fuels},
volume = {30},
number = {10},
pages = {8055--8064},
publisher = {American Chemical Society},
abstract = {This work examines the effect of the absolute pressure (0.1 or 1.0 MPa) and the addition of a high-ash rejected material from municipal solid waste (MSW) composting (RC) on the slow pyrolysis of two-phase olive mill waste (OW). The experiments were conducted in a batch pyrolysis system using an initial mass of 750 g of feedstock. Three types of initial materials were tested: the OW alone, a mixture of OW and pure additives (5 wt % K2CO3 and 5 wt % CaO), and a mixture of OW and RC (10 wt %). For the OW without any additive, an increased pressure led to a market increase in the carbonization efficiency (i.e., fixed carbon yield). At atmospheric pressure, the addition of either additives (CaO + K2CO3) or RC led to important changes in the pyrolysis behavior as a result of the catalytic role of the alkali and alkaline earth metals (AAEMs). However, this catalytic effect, which is translated into an enhancement of the decomposition of both the hemicellulose and cellulose fractions, was not observed at 1.0 MPa. The potential stability of all of the produced biochars appeared to be very high, given the results obtained from both proximate and ultimate analyses. This high stability was confirmed by 13C and 1H solid-state nuclear magnetic resonance, which showed that the carbon contained in the biochars was composed mainly or entirely of highly condensed aromatic structures. However, the highest values of stable C (Edinburgh stability tool) and R50,x (recalcitrance index) were obtained for biochars produced from the OW + RC mixtures at any pressure. In summary, the addition of the rejected material from MSW composting appears to be a very cost-effective measure to obtain a potentially high-stable biochar, even at atmospheric pressure.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This work examines the effect of the absolute pressure (0.1 or 1.0 MPa) and the addition of a high-ash rejected material from municipal solid waste (MSW) composting (RC) on the slow pyrolysis of two-phase olive mill waste (OW). The experiments were conducted in a batch pyrolysis system using an initial mass of 750 g of feedstock. Three types of initial materials were tested: the OW alone, a mixture of OW and pure additives (5 wt % K2CO3 and 5 wt % CaO), and a mixture of OW and RC (10 wt %). For the OW without any additive, an increased pressure led to a market increase in the carbonization efficiency (i.e., fixed carbon yield). At atmospheric pressure, the addition of either additives (CaO + K2CO3) or RC led to important changes in the pyrolysis behavior as a result of the catalytic role of the alkali and alkaline earth metals (AAEMs). However, this catalytic effect, which is translated into an enhancement of the decomposition of both the hemicellulose and cellulose fractions, was not observed at 1.0 MPa. The potential stability of all of the produced biochars appeared to be very high, given the results obtained from both proximate and ultimate analyses. This high stability was confirmed by 13C and 1H solid-state nuclear magnetic resonance, which showed that the carbon contained in the biochars was composed mainly or entirely of highly condensed aromatic structures. However, the highest values of stable C (Edinburgh stability tool) and R50,x (recalcitrance index) were obtained for biochars produced from the OW + RC mixtures at any pressure. In summary, the addition of the rejected material from MSW composting appears to be a very cost-effective measure to obtain a potentially high-stable biochar, even at atmospheric pressure.