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The term ‘acid sulfate soils’ (ASS) was coined by the Working Party on Nomenclature and Methods for the first International Symposium on Acid Sulfate Soils (1972, Wageningen) to mean soils that contain, or have the potential to produce, sulfuric acid in quantities that cause significant and long-lasting changes in key soil properties. [22]
Soil acidification is the buildup of hydrogen cations, which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate, which reacts in the soil to release protons.
Sulfuric acid is a very important commodity chemical; a country's sulfuric acid production is a good indicator of its industrial strength. [10] Many methods for its production are known, including the contact process, the wet sulfuric acid process, and the lead chamber process. [11] Sulfuric acid is also a key substance in the chemical industry.
The pH of a natural soil depends on the mineral composition of the parent material of the soil, and the weathering reactions undergone by that parent material. In warm, humid environments, soil acidification occurs over time as the products of weathering are leached by water moving laterally or downwards through the soil.
A mixture of ammonia gas and water vapor is introduced into a reactor that contains a saturated solution of ammonium sulfate and about 2% to 4% of free sulfuric acid at 60 °C. Concentrated sulfuric acid is added to keep the solution acidic, and to retain its level of free acid. The heat of reaction keeps reactor temperature at 60 °C. Dry ...
Phosphogypsum is a by-product from the production of phosphoric acid by treating phosphate ore with sulfuric acid according to the following reaction: . Ca 5 (PO 4) 3 X + 5 H 2 SO 4 + 10 H 2 O → 3 H 3 PO 4 + 5 (CaSO 4 · 2 H 2 O) + HX
The lead chamber process for sulfuric acid production was abandoned, partly because it could not produce sulfur trioxide or concentrated sulfuric acid directly due to corrosion of the lead, and absorption of NO 2 gas. Until this process was made obsolete by the contact process, oleum had to be obtained through indirect methods. Historically ...
Sodium bisulfate, also known as sodium hydrogen sulfate, [a] is the sodium salt of the bisulfate anion, with the molecular formula NaHSO 4.Sodium bisulfate is an acid salt formed by partial neutralization of sulfuric acid by an equivalent of sodium base, typically in the form of either sodium hydroxide (lye) or sodium chloride (table salt).