Case studies of dicyandiamide in industrial applications

📌 Core Advantages

✅ Non-polar-polar dual functional group design (Adsorption molecular weight: 150-2000Da)

✅ Adsorption rate increased by 80% (Test data)

✅ Acid and alkali resistant (pH 2-12), high temperature resistant (180℃)

✅ Regeneration efficiency reaches 95% (Reusable for over 50 cycles)

🔬 Full Production Process

❶ Raw Material Pre-treatment (Key Step)

- Mix formaldehyde solution (37% concentration) with dicyandiamide at a molar ratio of 1:1.2

- Stirring temperature controlled at 40-50℃ (error)

- pH value controlled at 8.5±0.3 (adjusted with buffer solution)

❷ Polymerization Reaction (Core Control Point)

- React in a constant temperature water bath (60±1℃) for 6-8 hours

- Rate control: 500rpm for the first 2 hours, 300rpm for the subsequent period

- Solution viscosity monitoring (Target: 120-150cp)

❸ Post-processing

- Centrifugal washing (300rpm×15min×3 times)

- Vacuum drying (60℃×24h)

- Particle size control: 0.3-0.8mm (Passugh 200 mesh sieve)

Basic Formula (kg):

Dicyandiamide 100

Formaldehyde solution 120

Sodium hydroxide 8

Water 800

Upgraded Formula (30% more efficient):

Add 5% quaternary ammonium salt surfactant

Introduce -SiO2 filler

Adopt gradient polymerization process

🌍 Practical Application Scenarios

🍵 Food Processing Case:

A tea factory (processing 500 tons/year) after:

- Tea polyphenol residue reduced to 0.02mg/kg (National standard ≤0.1)

- Adsorption time shortened to 15min (Traditional resin 60min)

- Annual savings on activated carbon procurement: 280,000 yuan

💊 Pharmaceutical Industry Case:

Decolorization of a traditional Chinese medicine ex- Adsorption capacity: 2.3mg/g (Activated carbon 0.8mg/g)

- Color difference value ΔE≤1.5 (National standard ≤3.0)

- Production line retrofitting cycle shortened to 3 days

🧴 Daily Chemicals Application:

Cosmetic decolorization:

- Hue stability improved (Color difference ΔE<0.8)

- Recommended stirring speed: 800-1000rpm

- Regeneration liquid recovery rate 92%

💧 Water Treatment Scenario:

Dyeing wastewater treatment:

- COD removal rate: 98.7% (Compared to activated carbon 92%)

- Effluent color ≤20 (National standard ≤30)

- Operating cost reduced by 0.35 yuan/ton

⚠️ Safety Operation Guidelines

1️⃣ Storage Conditions:

- Sealed and protected from light (refrigeration recommended at 5℃)

- Store isolated from strong oxidants

- Test free formaldehyde content monthly (<0.1%)

2️⃣ Firefighting Measures:

- Extinguishing agent: Dry powder/Carbon dioxide

- Evacuate immediately if smoke concentration >1000ppm

- May explode in fire if temperature >400℃

3️⃣ Waste Liquid Treatment:

- Neutralization treatment (Discharge after pH>11)

- Ion exchange treatment (Heavy metal recovery)

- Incineration treatment (Hazardous waste code 900-214-08)