(504e) Simultaneous Catalytic Conversion of Bio-Oil and Bio-Char for Hydrogen Production

Based on the integrated processes for hydrogen production from biomass, the simultaneous catalytic conversion of bio-oil and bio-char for hydrogen production was investigated in this paper. The potential hydrogen (H₂+CO) yield was increased from 45.70 to 82.19 mmol/g bio-oil with the presence of metals in the bio-char. The effects of metals (K, Ca, Mg, Fe, Zn, and Al) in bio-char on the catalytic conversion of bio-char and bio-oil were also investigated. The catalytic activities of the metals for the conversion of bio-char and bio-oil were followed by the sequence K>Ca>Mg>Fe>Zn>Al. Meanwhile, the alkali and alkaline earth metals (AAEM), including K, Ca, and Mg, were found to play the dominating roles among the metals in bio-char, and the catalytic effect of K was the most obvious. The potential hydrogen yield and tar yields were 143.50 mmol/g bio-oil and 4.96 mg/g bio-oil when adding the metal of 5 wt.% K.

The effects of metals on the biochar and biomass pyrolytic vapor (bio-oil) were investigated. Al had an inhibition on the catalytic activity of biochar, as a result, the soot yield was increased. Naphthalene was the primary tar in reaction temperature was 900 °C, also had a thermal stable in 900 °C. Fe was deactivated by coke and sintering easily.

The integrated process for hydrogen production from biomass was developed

Basing on the gas-solid simultaneous gasification process of the integrated processes of biomass, the effects of metals (K, Ca, Mg, Fe, Zn, and Al) in biochar on the catalytic gasification and catalytic reforming processes were investigated in this paper.

The catalytic reforming of biomass pyrolytic vapor (MPV) over biochar in a fixed bed was investigated. The carbon conversion and potential hydrogen yield of biomass pyrolytic vapor were increased respectively from 68.46% to 86.88% and 42.16% to 82.76% in the presence of biochar. The catalytic reforming activities of different metals were found with the following the sequence: K>Ca>Mg>Fe>Zn>Al. Meanwhile, the alkali and alkaline earth metals (AAEM) like K, Ca, and Mg were found to play the dominating roles in the conversion of MPV, and especially, the catalytic effect of K was the most obvious among the metals in bio-char. The carbon conversion and potential hydrogen yield of pyrolytic vapor were increased by increasing temperature and ratio of steam to pyrolytic vapor.

The effects of metals on the biochar catalytic gasification were also investigated. The catalytic activities of metals on biochar catalytic gasification were in the sequences: K>Ca>Mg>Zn>Fe>Al. AAEM (K, Ca and Mg) and Fe can promote water-gas shift reaction, while Al had an inhibition effect on water-gas shift reaction. The increasing of temperature and steam were benefit for biochar catalytic gasification. When the carbon conversion was more than 90% (S = 20 g/h and T =900 °C), biochar and demineralized biochar need 40 min and 115min respectively.

The effects of metals on the biochar and biomass pyrolytic vapor (bio-oil) simultaneous catalytic conversion were investigated. The potential hydrogen (H₂+CO) yield was increased from 45.70 to 82.19 mmol/g bio-oil with the presence of metals in the biochar. And the tar yield was decreased from 24.88 to 13.84 mg/g bio-oil. The catalytic conversion of biochar and bio-oil were followed by the sequence K>Ca>Mg>Fe>Zn>Al. Meanwhile, the potential of hydrogen and tar yields were 143.50 mmol/g bio-oil and 4.96 mg/g bio-oil when adding the metal of K. The performance of AAEM (K, Ca and Mg) was comparable with Ni in catalytic reforming bio-oil. AAEM can promote water-gas shift and methane reforming reactions, also promote the elimination of soot. Al had an inhibition on the catalytic activity of biochar, as a result, the soot yield was increased. Naphthalene was the primary tar in reaction temperature was 900 °C, also had a thermal stable in 900 °C. Fe was deactivated by coke and sintering easily.