00559naa#a2200193#i#450# EN\\bibl\125574 20260619215131.5 3034-4689 20260601b2026####ek#y0engy0150####ca RU IMPROVING THE PERFORMANCE OF THE VORTEX COLUMN CONCENTRATION OF SULFURIC ACID Journal article Kazan Kazan National Research Technological University 2026 4 с. Journal article local Sabirov I. M. Fazullin R. H. vestniktu.ru