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Catalytic Conversion of Carbon Dioxide by Metal-Organic Frameworks: an Effective Approach for CO2 Utilization
2023
Tayebi, Leila | Rahimi, Rahmatollah | Akbarzadeh, Ali Reza
Due to the increase in carbon dioxide emission, there is a need for achieving efficient ways to reduce CO2 harmful effects. There are several strategies to mitigate atmospheric CO2 concentration. The catalytic cycloaddition of carbon dioxide with epoxides to provide cyclic carbonates employing metal-organic frameworks is a promising method for this purpose. Herein the application of two porous porphyrinic MOFs (Co-PMOF and Cu-PMOF) as catalysts in CO2 conversion was investigated. These MOFs demonstrated good crystallinity and porosity, providing them with two promising platforms to study CO2 conversion reactions. These heterogeneous porphyrin-based MOFs are catalytically efficient towards the chemical conversion of CO2 under moderate conditions because these MOF matrices contain a high density of active Lewis acidic and basic sites for activating CO2 and epoxide compounds. These MOFs exhibited high catalytic efficiency for the chemical fixation of CO2 at ambient temperature and solvent-free conditions. The reactions formed the proportionate cyclic carbonates in good yields. These products are valuable compounds in a variety of chemical fields.
Показать больше [+] Меньше [-]Estimation and modeling of gas emissions in municipal landfill (Case study: Landfill of Jiroft City)
2017
Ghasemzade, Reza | Pazoki, Maryam
One of the major factors, contributing to the emission of greenhouse gases in the environment is generation of pollutant gases in municipal landfills. As for the design and building of a gas collecting system, it is necessary to properly estimate the amount and type of the landfill emissions. By means of LandGEM model, this study predicts the amount and type of the landfill gases, produced for 30 years (from 2016 to 2045) in Jiroft. Results show that in 2045, 3, 324, 274 tons of waste will be disposed in municipal landfills of Jiroft and the total amount of produced gas, methane, carbon dioxide, and non-methane organic compounds will be 32, 994, 8813, 24,181, and 378.8 tons/year, respectively. Furthermore, the rate of landfill gas emissions from 2016 to 2045 has been achieved. Maximum concentrations of methane, carbon dioxide and non-methane organic compounds in 2045, in 700 meters from landfill, will be 40, 590, 112, 700, and 1765 tons/m3 respectively. Based on the results, obtained from this article, landfill pollutants such as CH4, CO2, and NMOC's can reach up to 15 kilometers from landfill, thus social places should be located farther than 15 kilometers from the landfill site of Jiroft. The results, obtained in this paper, can be used to identify the effect of Jiroft landfill in global emission of greenhouse gases and proper management of the landfill gas not only reduces greenhouse gas emissions, diminishing their effects on public health, but can be also used as a sustainable energy source.
Показать больше [+] Меньше [-]Application of the Triangular Model in quantifying landfill gas emission from municipal solid wastes
2019
Yusuf, R. O. | Adeniran, J. A. | Sonibare, J. A. | Noor, Z. Z.
Municipal solid waste landfills are significant parts of anthropogenic greenhouse gas emissions. The emission of significant amount of landfill gas has generated considerable interest in quantifying such emissions. The chemical composition of the organic constituents and potential amount of landfill gas that can be derived from the waste were determined. The chemical formulae for the rapidly biodegradable waste (RBW) and slowly biodegradable waste (SBW) were determined as C39H62O27N and C36H56O20N, respectively. The triangular method was used to calculate landfill gas obtainable from rapidly biodegradable waste over a 5-year period and for slowly biodegradable waste over a 15-year period. A plot was obtained for a landfill life span of 20 years. The volume of methane and carbon dioxide from RBW were 12.60 m3 and 11.76 m3 respectively while those from SBW were 6.60 m3 and 5.48 m3 respectively at STP. For the initial deposit of 2002 the highest landfill gas emission rate occurred in 2007 at 0.2829 Gg/yr with an average cumulative emission of 0.3142 Gg while for a landfill closed after five years the highest landfill gas emission rate was in 2010 at 1.2804 Gg/yr with an average cumulative emission of 1.5679 Gg while this cumulative emission will start declining by the year 2029.
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