Abstract
Biomass gasification is a promising way to obtain “green energy”, but the gas composition makes it unsuitable for use in traditional technologies (i.e., IC engine). Gas purification over nickel and/or iron catalysts is an attractive alternative. Cellulose-based carbon aerogels (CAGs) have shown suitable physical chemical properties for use as catalyst supports. In this work, nickel and iron catalysts are supported on CAG made from cellulose microfibers. Microfibers were impregnated with (NH4)2SO4 to increase the mass yield. Carbonization was evaluated at different heating rates, maximum temperatures, and dwell times to generate CAGs. Resulting chars were characterized by N2 adsorption, X-ray diffraction (XRD), and Raman spectroscopy. The CAG with better properties (specific surface, pore size, thermal resistance) was impregnated with the metal precursor salt via incipient wetness and treated with H2. Catalysts were characterized by transmission electron microscopy (TEM), XRD, N2 adsorption, and inductively coupled plasma optical emission spectrometry (ICP-OES). Ammonia adsorption was studied over CAG and catalysts to estimate the thermodynamic parameters. The impregnation with ((NH4)2SO4 improves thermal resistance of the char obtained from carbonization. The catalysts exhibit higher adsorption capacity than CAG (without metal), indicating chemical interaction between ammonia and metals. The metal-ammonia interaction is stronger on Fe than on Ni catalyst, which is consistent with reported theoretical calculations.
Highlights
Biomass is an abundant and easy to harvest resource, but faces difficulties associated with distribution logistics
Several authors have reported the use of carbon aerogels (CAG) as catalyst supports for the conversion of organic compounds that can be classified as tar
Ábrahám et al published a study about the acetic acid hydroconversion reaction over Mo/CAGs catalysts; their results show that the reaction pathways and product distributions are controlled by the accessibility of carbon surface, as well as by the amount and shape of Mo particles [51]
Summary
Biomass is an abundant and easy to harvest resource, but faces difficulties associated with distribution logistics (collection, transportation, and distribution). Biomass, especially wood, has lower energy density (2–3 GJ/m3 ) than other common fuels such as ethanol (23 GJ/m3 ). Gasoline (35 GJ/m3 ) [1,2]. One of the most traditional and promising technologies for converting solid biomass into energy, fuels and commodities is gasification [3], but obtaining the desired products can be challenging. Molino et al [4] have reported that Pine sawdust gasification result in Catalysts 2018, 8, 347; doi:10.3390/catal8090347 www.mdpi.com/journal/catalysts. Catalysts 2018, 8, 347 a syngas composition with high content of CO (35–43%) and H2 (21–39%), while CH4 (6–10%) and CO2 (18–20%) appear in lower concentrations. Changing biomass type by α-cellulose the balance is quite different with less CO (6.5–11.2%), H2 (13.5–18.5%), and CH4 (2.2–3.7%) and increasing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
