A Biomass-Supported Na2CO3 Sorbent for Flue Gas Desulfurization

• Published in: Environmental science & technology Vol. 37; no. 11; pp. 2596 - 2599
• Main Authors: Shang, Hongshan, Ouyang, Ti, Yang, Fan, Kou, Yuan
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.06.2003
• Subjects: Adsorption; Air Pollutants - chemistry; Air Pollution - prevention & control; Applied sciences; Atmospheric pollution; Biomass; Carbonates - chemistry; Exact sciences and technology; Gases; General processes of purification and dust removal; Incineration; Plant Leaves; Poaceae; Pollution; Prevention and purification methods; Sulfur; Sulfur Dioxide - chemistry; Desulfurization; Dry process; Plant leaf; Sulfur dioxide; Vegetal waste; Straw; Gas solid adsorption; Impregnated material; Upgrading; Waste reuse; Sodium carbonate; Physicochemical purification; Agricultural waste; Adsorbent; Flue gas purification; Breakthrough curve
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es021026o

A novel sorbent for SO2 removal has been investigated. The sorbent is obtained by conventional incipient wetness impregnation of abandoned biomaterials (straw or dried leaves) with an aqueous solution of Na2CO3. A material with the composition 80 wt % Na2CO3/straw shows a desulfurization activity which is both higher and faster than that of the reference sample Na2CO3/γ-Al2O3. The breakthrough and stoichiometric SO2 adsorption efficiencies for 80 wt % Na2CO3/straw reach 48.9% and 80.6%, respectively, at a temperature of 80 °C. The adsorption efficiencies are almost constant in the temperature range 70 to 300 °C. According to IR and XPS analysis the main products observed on the spent sorbent are sulfite below 150 °C and sulfate at 300 °C. The Na2CO3 in 80 wt % Na2CO3/straw can potentially be recycled by the oxidation of the straw with concomitant reduction of the sulfite species to elemental sulfur, making the proposed process CO2 neutral.