Here’s a detailed list of green alternatives to commonly used hazardous chemicals, along with explanations of why they are safer:
1. Solvents
- Hazardous chemical: Benzene, toluene, chloroform, carbon tetrachloride
- Green alternative: Water, ethanol, supercritical CO₂, ethyl lactate
- Why: Non-toxic, biodegradable, and less volatile, reducing air and water pollution.
2. Oxidizing Agents
- Hazardous chemical: Chromium(VI) compounds, chlorine gas, permanganates
- Green alternative: Hydrogen peroxide (H₂O₂), oxygen (O₂), enzyme-based oxidants
- Why: Hydrogen peroxide decomposes into water and oxygen, leaving no toxic residues.
3. Reducing Agents
- Hazardous chemical: Sodium borohydride in large excess, lithium aluminum hydride
- Green alternative: Ascorbic acid (Vitamin C), catalytic hydrogenation using H₂
- Why: Safer, generates minimal waste, and often uses water as a medium.
4. Acids & Bases
- Hazardous chemical: Strong mineral acids like concentrated H₂SO₄, HCl; strong bases like NaOH
- Green alternative: Citric acid, acetic acid, sodium bicarbonate
- Why: Weaker acids and bases are less corrosive, safer to handle, and biodegradable.
5. Plastics & Polymers
- Hazardous chemical: Polyvinyl chloride (PVC), polystyrene (styrofoam)
- Green alternative: Polylactic acid (PLA), polyethylene from sugarcane, starch-based polymers
- Why: Biodegradable, renewable, and produce fewer toxic byproducts during degradation.
6. Pesticides & Herbicides
- Hazardous chemical: Organophosphates, DDT
- Green alternative: Neem oil, Bacillus thuringiensis (Bt) bacteria, pyrethrins from flowers
- Why: Natural, biodegradable, and target pests without harming soil, water, or non-target organisms.
7. Soluble Coatings and Paints
- Hazardous chemical: Solvent-based paints (with VOCs – volatile organic compounds)
- Green alternative: Water-based paints, low-VOC paints
- Why: Reduce air pollution and health risks associated with inhalation of toxic fumes.
8. Energy & Reaction Media
- Hazardous chemical: Fossil-fuel-based solvents, energy-intensive heating methods
- Green alternative: Microwave or ultrasonic-assisted reactions, solvent-free conditions
- Why: Reduce energy consumption, emissions, and chemical waste.