pH Buffers and Controllers

pH buffers maintain stable pH during processing preventing fluctuations critical for dye fixation, enzyme activity, and chemical stability across pH range 2-13. Buffer systems include acetic acid and sodium acetate (pH 3.5-5.5, 5-20 g/L for acid dyeing), phosphate buffers (pH 6-8 for enzyme treatments and neutral dyeing), carbonate and bicarbonate (pH 9-11, soda ash 10-40 g/L for reactive dyeing providing alkalinity for fixation), and proprietary buffer systems (pH 4-11, 2-10 g/L, multifunctional). Acids include acetic acid (pH 2-6, 1-10 mL/L), formic acid (pH 2-4, 0.5-5 mL/L), sulfuric acid (pH 1-3, rarely used), and citric acid (pH 3-6, bio-based, 2-15 g/L). Alkalis include sodium hydroxide (pH 11-14 for mercerization 200-300 g/L), sodium carbonate (pH 9-11, reactive dyeing standard 10-40 g/L), ammonia (pH 9-11, wool dyeing 1-5 mL/L), and sodium bicarbonate (pH 8-9.5, enzyme treatments 5-20 g/L). Applications span reactive dyeing maintaining pH 10.5-11.5, acid dyeing pH 4-6, disperse dyeing pH 4.5-5.5, enzyme treatments pH 7-9, and bleaching pH 10.5-11 with environmental concerns about phosphate eutrophication driving non-phosphorus alternatives.