Catalase for Textile Bleach Cleanup — Hydrogen Peroxide Removal Before Reactive Dyeing
Remove residual H2O2 after hydrogen peroxide bleaching of cotton and linen in a single enzymatic step, protecting dye bath performance and eliminating the need for chemical reducing agents.
Hydrogen peroxide is the dominant bleaching agent in modern cotton and linen processing. After the bleach bath, however, residual H2O2 carried into the dye bath causes shade variation, poor dye fixation, and — in reactive dyeing — irreversible hydrolysis of the chromophore before it bonds to the fiber. The standard chemical remedy, sodium bisulfite or sodium thiosulfate reducing agents, introduces additional chemistry, increases effluent load, and adds a rinsing step. Catalase enzyme for textile bleaching offers a cleaner alternative: the enzyme decomposes residual hydrogen peroxide directly into water and oxygen, leaving no chemical carryover. The reaction is fast, specific, and operates under normal wash-off conditions. Catalase enzyme from Aspergillus niger or Micrococcus lysodeikticus, at activity grades of 50,000–200,000 U/g, fits the pH and temperature window of typical post-bleach rinse baths — pH 6.0–8.0 and 20–50°C. The enzyme is active even at ambient temperatures, which is commercially important because it allows mills to skip the energy cost of heating a reducing-agent bath. Dosage in textile bleach cleanup is typically 50–200 ppm on bath weight, with actual dose set by the residual H2O2 level, liquor ratio, and available contact time before the dye loading step. Mills using catalase enzyme for textile bleaching report more consistent dye uptake, fewer shade variations across lots, and lower rework rates — all directly linked to eliminating the oxidant interference. For technical buyers evaluating catalase enzyme for reactive dyeing preparations, the critical parameters are residual peroxide target (ideally below 2 ppm), treatment time, pH compatibility with the wash bath, and whether powder or liquid format suits the dosing system. Full COA and TDS documentation is available for supplier qualification.
Post-bleach peroxide removal for reactive dyeing
Reactive dyes hydrolyze in the presence of residual H2O2 before bonding to cotton, causing reduced color depth and poor exhaustion. Catalase enzyme added to the wash-off bath at 50–150 ppm on liquor weight, pH 6.5–7.5, and 30–50°C decomposes H2O2 within 10–20 minutes of contact time, allowing the dye bath to load onto a peroxide-free substrate. Results include improved shade consistency and reduced unfixed dye in effluent.
Replacing sodium bisulfite in continuous pad-steam lines
Continuous pad-steam bleaching lines often use sodium bisulfite or sodium thiosulfate as anti-chlor or peroxide scavengers in the wash-off compartments. Catalase enzyme can replace these reducing agents entirely, eliminating sulfite in the effluent, reducing total dissolved solids (TDS), and simplifying the wastewater treatment chemistry. Typical dosing in continuous systems is 100–200 mL/min enzyme solution added to the final wash compartment, with pH maintained at 6.5–8.0.
Batch dyeing kier and overflow machine bleach cleanup
In batch-process kiers and overflow dyeing machines, catalase enzyme is added after the hot peroxide bleach and before draining or dyeing loading. The enzyme treats the residual peroxide in the bath liquor without requiring a separate drain-fill cycle, saving water, energy, and process time. At 20–40°C and pH 6.5–8.0, a 10–20-minute enzyme contact is usually sufficient to reduce H2O2 to below 2 ppm before the reactive or direct dye is loaded.
Linen and bast fiber bleach cleanup
Linen, ramie, and jute bleaching often uses alkaline peroxide at higher temperatures, leaving higher residual H2O2 than cotton processes. After the high-temperature bleach, fabrics are cooled and pH adjusted to 6.5–8.0 before catalase enzyme addition at 100–250 ppm on bath weight. The enzyme acts on free peroxide rapidly, with most decomposition complete within 15–25 minutes at 30–45°C. This step protects the subsequent dyeing or finishing chemistry from oxidant interference.
| Parameter | Value |
| Activity range | 50,000 – 200,000 U/g |
| Optimal pH | 6.0 – 8.0 |
| Optimal temperature | 20°C – 50°C |
| Form | Dark brown powder or liquid |
| Shelf life | 12 months (sealed, cool, dry place) |
| Packaging | 25 kg drums / 25 kg jerricans |
Frequently Asked Questions
How does catalase enzyme replace sodium bisulfite in textile bleach cleanup?
Sodium bisulfite chemically reduces residual H2O2 by consuming it through a reductive reaction, but this adds sulfite to the effluent and can affect pH. Catalase enzyme decomposes H2O2 enzymatically into water and oxygen, leaving no chemical residue and adding no additional TDS to the liquor. Both achieve the goal of peroxide removal before dyeing, but catalase eliminates the sulfite chemistry entirely. For mills targeting lower effluent COD and TDS, catalase enzyme is often the preferred choice. The dosage window for catalase in textile bleach cleanup is typically 50–200 ppm on bath weight, which is practical for both batch and continuous processes.
What residual H2O2 level is acceptable before reactive dyeing?
Most reactive dyeing processes require residual H2O2 below 2 ppm before the dye bath is loaded. At higher peroxide levels, the reactive chromophore hydrolyzes before bonding to the cotton fiber, causing pale shading, poor color fastness, and inconsistent lot-to-lot results. Catalase enzyme treatment at 50–150 ppm on bath weight, pH 6.5–7.5, and 30–50°C typically reduces residual H2O2 to below 2 ppm within 10–20 minutes, providing a reliable cleanup step before dyeing.
What is the correct dosage of catalase enzyme for textile bleaching applications?
Dosage depends on the initial residual H2O2 concentration, bath ratio, temperature, pH, and contact time. A practical starting point for batch processes is 50–150 ppm on liquor weight when residual H2O2 is in the 200–500 ppm range after bleaching. Higher residuals from alkaline peroxide bleach at high temperatures may require 150–250 ppm. For continuous pad-steam lines, the enzyme is metered into the wash compartment based on fabric throughput and measured peroxide in the incoming liquor. Always verify with a peroxide strip test or titration before loading dye.
Does catalase enzyme work at ambient temperature in textile mills?
Yes. Catalase enzyme from Aspergillus niger and Micrococcus lysodeikticus maintains useful activity at 20–30°C, which is commercially important in mills that cannot heat the wash-off bath. The reaction is somewhat faster at 40–50°C, but even at room temperature, catalase enzyme decomposition of H2O2 is substantially complete within 15–30 minutes at a suitable dose and pH of 6.0–8.0. This ambient-temperature activity reduces energy consumption compared to heating a reducing-agent bath.
Get Catalase for Your Textile Line
Tell us your application, peroxide load, and target residual. We'll recommend the right activity grade, send a free 100 g sample with COA, and quote bulk pricing.
Get Quote