Disulfate Ion as an Intermediate to Sulfuric Acid in Acid Rain Formation

Abstract Algae, which contains most of the marine biogenic sulfur (S), is the main producer of dimethylsulfide (DMS). The oxidation products of DMS (methanesulfonic acid (MSA) and non-sea salt sulfates (nss-SO42-)) are important contributors to acid rain acidity (~ 40%) and have great influence on global climate change and acid rain formation. The biogenic S of red algae mainly exists in carrageenan molecules, the polysaccharide extract of red algae. In this work, the carrageenan biogenic S was fixed into biochar aerogel (SCA) synchronically by pyrolysis with the assistance of the unique hydrogel property of carrageenan. During this process, 89% of C and 96% of marine biogenic S are preserved in SCA, efficiently preventing the loss of C and S element. More importantly, the thiophene S structure in SCA framework derived from the marine biogenic S could endow the carbon aerogel superior electrocatalysis activity by regulating the charge density of adjacent C atoms. For instance, thiophene S structure can promote the cleavage and protonation of N2 molecules and efficiently lower the energy barrier of the promote the protonation of N2, thus greatly enhance the activity of electrocatalytic NRR. This study provided a promising avenue for the synchronization fixation of marine biogenic S and C to reduce the the formation of acid rain and carbon dioxide emissions. It also developed a green and sustainable way to synthesize high-performance biochar materials for advanced energy conversion.

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Improved Acid Rain Resistance of High Calcium Fly Ash-sodium Hydroxide Geopolymer Mortar Cured at Ambient Temperature by Incorporating Rice Husk Ash

The Journal of Solid Waste Technology and Management ◽

10.5276/jswtm/2021.324 ◽

2021 ◽

Vol 47 (2) ◽

pp. 324-331

Author(s):

Prinya Chindaprasirt ◽

Kiatsuda Somna

Keyword(s):

Compressive Strength ◽

Sulfuric Acid ◽

Fly Ash ◽

Nitric Acid ◽

Acid Rain ◽

Rice Husk ◽

Rice Husk Ash ◽

Acid Resistance ◽

Portland Cement Concrete ◽

High Calcium

Geopolymer is an aluminosilicate material, synthesized from source materials rich in silica and alumina and alkali solution. This product provides similar strength to Portland cement concrete. Geopolymer exhibits a wide variety of properties and characteristics, including high compressive strength, low shrinkage, acid resistance, fire resistance and low thermal conductivity. In term of acid resistance, acid rain is an important consideration due to global warming. Structures deteriorate as a result of persistence contact with acid rain with of pH less than 5. Thus, this research aims to improve acid resistance of fly ash-NaOH geopolymer mortars by incorporating rice husk ash (RHA). Artificial acid rain solution was prepared by mixing nitric acid and sulfuric acid at the ratio of 70:30 v/v. The geopolymer mortars were immersed in 5% nitric acid, 5% sulfuric acid, and 5% synthetic acid rain solutions for 36 weeks. The evaluations of its resistance to acid solution was investigated with surface corrosion, compressive strength, and microstructure. The results showed that the incorporation of RHA improved the acid rain resistance of geopolymer mortar through pore refinement and increase in strength. The mortar with fly ash to RHA ratio of 90:10 provided the highest compressive strength and good resistance to acid rain.

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Acid rain formation through catalytic transformation of sulfur dioxide over clay dusts: remarkable promotion by a vicinal aluminium site

Catalysis Science & Technology ◽

10.1039/d0cy02069a ◽

2021 ◽

Vol 11 (3) ◽

pp. 785-789

Author(s):

Gang Yang ◽

Lijun Zhou

Keyword(s):

Sulfur Dioxide ◽

Acid Rain ◽

Molecular Oxygen ◽

Molecular Level ◽

Catalytic Transformation ◽

Rain Formation

Mechanisms for catalytic SO2 transformation to H2SO4 over clay dusts have been unraveled at a molecular level. All O atoms in ozone (especially molecular oxygen) are effective oxidants due to remarkable promotion of a vicinal Al3+ site.

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