Removal of Toxic Dye Pollutants from wastewater
Introduction Application Best Features Technical Data Download Links FAQ’S

 

Introduction


DyeOxy® and DyeSorb® is a two-step process for the removal of all types of dyes including many other pollutants from water or wastewater. The most effective process to attain the efficient degradation of industrial dyes. Dyes are used in various industries as coloring agents. The discharge of these dyes, specifically synthetic dyes in wastewater represent a serious environmental problem and cause public health concerns.

Dyes consist of many toxic materials and causing serious harmful impacts on the environment. Tons of dyes are discharged daily into the environment as aquatic waste. The wastewater from these industries contains very high levels of Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD).

 

 

Applications

Textile Dyeing Industry

Industrial Wastewater

Leather Industry

Plastic Industry

 

 

Best Features

 

  • Capturing and degradation of toxic dyes pollutants
  • Removes excessive concentration of color, BOD, and COD
  • Simple, economical and highly effective
  • Helps to make water cleaner
  • Removal of Organic, Cationic, and Anionic Dyes
  • Advanced Technology

 

 

 

 

Properties of DYEOXY®


Physical Properties
Type Advanced Oxidation
Physical Form Crystalline (Triclinic)
Color White Crystalline Powder
Bulk Density ca. 980 – 1020 kg/m3
Odor None
Dosing Min 10 g/m3
Max 50 g/m3

Properties of DYESORB®


Physical Properties
Type MOF’s Adsorber
Physical Form Solid Granules
Color Black
Particle size 0.5 – 2.0 mm
Bulk Density ca. 620 – 680 kg/m3
Operating Parameters
Flow Direction Down Flow
Freeboard 40%
Regeneration Yes
Minimal Bed Depth US 31.5 inch
SI 80 cm
Optimal Bed Depth US 47 inch
SI 120 cm
Service Velocity US 6 – 12 gpm/ft2
SI 15 – 30 m/h
Backwash Velocity US 10 – 12 gpm/ft2
SI 25 – 30 m/h

 

 

 

Download Links

DyeOxy/DyeSorb Brochure

 

 

 

 

FREQUENTLY ASKED
QUESTIONS

DyeSorb® and DyeOxy® are complementary technologies developed by Watch Water® Germany for the removal and degradation of dyes, color, and organic pollutants from industrial wastewater.

  • DyeSorb® is a Metal-Organic-Framework (MOF)–based adsorber that traps and concentrates colorants and organic molecules.
  • DyeOxy® is a Sulfate-Radical-Based Advanced Oxidation Process (SR-AOP) that chemically decomposes the adsorbed or dissolved pollutants into harmless CO₂ and H₂O.

Used together, they provide a complete “adsorb + oxidize” solution that far outperforms conventional treatments.

Textile, leather, printing, and plastics industries discharge millions of liters of colored wastewater daily. Even at concentrations below 1 mg/L, synthetic dyes can:

  • ☛ Block light penetration and inhibit photosynthesis
  • ☛ Increase BOD and COD dramatically
  • ☛ Cause long-term toxicity to aquatic life and humans

Strict discharge limits now require complete color and COD removal before release or reuse — which DyeSorb® + DyeOxy® achieves efficiently.

Step 1 – Adsorption (DyeSorb®):

  • ☛ Water passes through a fixed bed of DyeSorb® granules (Zinc-based MOF).
  • ☛ The media selectively captures both cationic and anionic dyes as well as organics.
  • ☛ Once saturated, DyeSorb® can be regenerated using oxidizing solution (e.g., Oxydes or DyeOxy®) for reuse.


Step 2 – Oxidation (DyeOxy®):

  • ☛ DyeOxy® releases sulfate (SO₄•–) and hydroxyl (HO•) radicals that attack and decompose organic molecules.
  • ☛ This two-in-one SR-AOP + HR-AOP system oxidizes the dyes into CO₂, water, and sulfates — without harmful by-products.
  • ☛ The process works at natural pH (~7), reducing the need for acid or base adjustment.

Unlike conventional Fenton or chlorine/ozone oxidation systems, DyeOxy®:

  • ☛ Uses sulfate radicals (SO₄•–) with higher oxidation potential and longer half-life
  • ☛ Generates both sulfate and hydroxyl radicals simultaneously
  • ☛ Works with Titansorb-P photocatalyst instead of iron, avoiding sludge generation
  • ☛ Operates effectively at neutral pH
  • ☛ Produces no chlorinated or brominated by-products

In textile wastewater:

  • ☛ Up to 95 % color removal within 120 minutes
  • ☛ COD and BOD substantially reduced
  • ☛ Operates at pH 7, ambient temperature
  • ☛ Minimal sludge or chemical residues

Recommended DyeOxy® dose:

  • ☛ 10 g/m³ (minimum)
  • ☛ 50 g/m³ (maximum, depending on pollution level)

A typical installation includes:

  • ☛ Collection/Equalization tank
  • ☛ Dosing of DyeOxy® powder into the stream or reaction tank
  • ☛ Recirculation with mixing and light exposure (for photo-Fenton effect)
  • ☛ Filtration or settling to remove precipitates
  • ☛ Polishing through DyeSorb® for final color and organics removal

Example: A 10 m³/h system requires a 30 m³ storage tank for optimum reaction time (×3 rule).

SO4•−+HO•+Dyes+Organics→CO2+H2O+SO42−SO₄^{•−} + HO^{•} + Dyes + Organics → CO₂ + H₂O + SO₄^{2−}SO4•−​+HO•+Dyes+Organics→CO2​+H2​O+SO42−​

Property Specification
Type MOF (Zinc-based cationic framework, DyeSorb® / Zincox)
Physical Form Solid granules
Color Black
Particle Size 0.5 – 2.0 mm
Bulk Density 620 – 680 kg/m³
Carbon Content ≥ 34 %
Zinc Content ≥ 66 %
Moisture ≤ 5 %
Adsorption Capacity 60 mg dye / g media
Surface Area ~ 3 000 m²/g
Regeneration Yes – reusable after oxidizer rinse
Property Specification
Type Sulfate Radical–Based Oxidizer (Advanced Oxidation)
Physical Form White crystalline powder
Bulk Density 980 – 1 020 kg/m³
Odor None
Minimum Dose 10 g/m³ wastewater
Maximum Dose 50 g/m³ wastewater
Parameter Recommended Range
Flow Direction Down-Flow
Freeboard 40%
Service Velocity 15 – 30 m/h (6–12 gpm/ft²)
Backwash Velocity 25 – 30 m/h (10–12 gpm/ft²)
pH Range Neutral (5–9)
Bed Depth 80 – 120 cm (31.5–47 in)
Regeneration Yes
  • ☛ Textile & dyeing plants
  • ☛ Paper & pulp mills
  • ☛ Leather tanning
  • ☛ Plastic and pigment manufacturing
  • ☛ Printing and packaging
  • ☛ Food & beverage colorant removal
  • ☛ Municipal wastewater reuse and color control
Conventional Process Limitation DyeSorb® + DyeOxy® Advantage
Flocculation / Alum / Polymer High sludge, poor color removal No sludge, complete degradation
Ion Exchange / Membrane Expensive, clogging, waste concentrate Simple, reusable, low operating cost
Chlorine / Ozone Oxidation Toxic by-products Non-toxic, sulfate radical oxidation
Fenton’s Reaction Requires acid pH and produces sludge Works at pH 7, no sludge

Yes. DyeSorb® can be fully regenerated within 2 hours using Oxydes or DyeOxy® solutions. Approximately 99 % of adsorbed dye can be released, allowing repeated use over years.

  • ☛ Zero toxic by-products
  • ☛ Minimal sludge generation
  • ☛ Low chemical consumption
  • ☛ Operates at neutral pH, saving acid/base costs
  • ☛ Water reuse–ready effluent suitable for discharge or recycling

Both products are manufactured in Mannheim, Germany by Watch Water® GmbH, a global leader in green-chemistry water treatment solutions. The company also produces Titansorb®, Ferrolox®, and SolarOxy® technologies used to enhance oxidation, adsorption, and regeneration performance.

  • ✅ Two-in-one solution for color and COD remova
  • ✅ Works at neutral pH – no pre- or post-neutralization
  • ✅ Reusable adsorbent – lower operational cost
  • ✅ No sludge or secondary pollution
  • ✅ Safe, non-chlorinated oxidation chemistry
  • ✅ Fast reaction and small footprint
  • ✅ Environmentally sustainable and fully Made in Germany