摘要:
A method for manufacturing high purity sulfuric acid is provided. A mixed solution subsequently undergoes a first preheating step, a second preheating step, a distilling step and an evaporating step to remove peroxide, water, oxygen and insoluble impurities, so as to obtain the first gas containing sulfur trioxide, sulfuric acid and hydrogen oxide. And then, the sulfur trioxide is absorbed by a sulfuric acid solution, thereby forming the high purity sulfuric acid.
摘要:
Spent, acidic solutions comprising cupric chloride and hyrdrochloric acid from the copper etching process are regenerated by a process in which the acid is subjected to distillation with sulfuric acid. In one embodiment, the process comprises (a) providing a spent etchant comprising at least about 10% by weight chloride and at least about 5% dissolved copper; (b) adding at least about 2 moles of sulfuric acid per mole of dissolved copper to the spent etching solution, thereby converting copper chloride into hydrochloric acid and precipitated copper sulfate; (c) distilling the mixture from step (b) to vaporize at least a portion of the hydrochloric acid; (d) condensing at least a portion of the vaporized hydrochloric acid; (e) separating at least a portion of the precipitated copper sulfate from the residual liquid, wherein said residual liquid comprises sulfuric acid; and (f) reusing at least a portion of the residual liquid as a sulfuric acid source in step (b).
摘要:
A process and apparatus for the regeneration of contaminated acid. The process involves cooling the contaminated acid to a lower temperature sufficient to form at least one liquid hydrate of the acid without forming a solid hydrate of the acid, maintaining the contaminated acid at the lower temperature for a time sufficient to form at least one liquid hydrate of the acid and precipitate an amount of the contaminants, separating the precipitated contaminants from the cooled acid, and warming the acid to decompose the liquid hydrate.
摘要:
A process and apparatus for the regeneration of contaminated acid. The process involves cooling the contaminated acid to a lower temperature sufficient to form at least one liquid hydrate of the acid without forming a solid hydrate of the acid, maintaining the contaminated acid at the lower temperature for a time sufficient to form at least one liquid hydrate of the acid and precipitate an amount of the contaminants, separating the precipitated contaminants from the cooled acid, and warming the acid to decompose the liquid hydrate.
摘要:
Method of purification by extraction of at least one substance to be isolated from a liquid medium, comprising an addition to the latter of an organic compound, entrainable by a vapor, which has a molecule with an acidic-basic character in the Lewis sense due to at least one atom of N, O and/or S forming one or more active sites provided with a free electron pair, this pair or these pairs being in resonance with at least one other pair carried by the molecule, this addition being carried out in a quantity sufficient to give rise to a product of an equilibrium reaction between the organic compound and the said at least one substance to be isolated, and sufficient to cause a precipitation of this equilibrium reaction product, a filtration of the precipitate and an entrainment by vapor of the organic compound from the precipitate, with a yield of the substance to be isolated in purified form.