I. Food and Beverage Industry

1. Food Additives

• Humectant: Used in bread, cakes, candies, and other foods to prevent moisture loss and extend shelf life (e.g., chocolate coatings, soft candies).

• Sweetener: Provides a mild sweet taste, suitable for low-calorie or sugar-free foods (e.g., chewing gum, jelly).

• Thickener/Stabilizer: Improves the texture of beverages (e.g., fruit juices, sports drinks) and sauces, preventing ingredient separation.

2. Brewing and Fermentation

• Acts as a preservative and flavor enhancer in wine production (e.g., wine, liqueurs); regulates microbial metabolism during fermentation.

3. Pet Food

• Maintains moisture in pet food and improves palatability, commonly used in canned and dry pet food.

II. Cosmetics and Personal Care Industry

1. Core Ingredient in Skincare Products

• Humectant: Widely used in creams, lotions, and facial cleansers to absorb moisture from the air and maintain skin hydration (e.g., glycerin often accounts for 5%-20% of skincare formulations).

• Solvent and Carrier: Dissolves active ingredients (e.g., vitamins, essential oils) and enhances formula stability.

2. Hair Care Products

• Added to shampoos and conditioners to reduce water evaporation from hair and improve dry, frizzy hair (e.g., hair oils, leave-in conditioners).

3. Personal Cleansing Products

• A key ingredient in soaps and body washes, enhancing product moisturization and preventing skin dryness after cleansing (e.g., handmade soaps may contain 10%-15% glycerin).

4. Oral Care

• Humectant and thickener in toothpaste to prevent the paste from drying and hardening, while improving taste.

III. Pharmaceutical and Biomedical Field

1. Pharmaceutical Excipients

• Solvent and Humectant: Used in oral liquids, syrups, and external ointments (e.g., frostbite creams, laxative suppositories) to increase drug solubility and maintain formulation moisture.

• Lubricant: Prevents adhesion during capsule production and improves tablet formability; adjusts hardness and disintegration rate in tablet preparation.

2. Biomedical Applications

• Serves as a cryopreservative for cell storage, preventing ice crystal formation in cells during low-temperature freezing (e.g., preservation of stem cells and blood products).

• Prepares glycerol suppositories to relieve constipation by utilizing its high osmotic pressure to promote intestinal peristalsis.

3. Pharmaceutical Synthesis Intermediate

• Used in the synthesis of antibiotics (e.g., penicillin), vitamins (e.g., vitamin C), and sedatives.

IV. Tobacco and Printing Industry

1. Tobacco Processing

• Acts as a tobacco humectant to prevent tobacco leaves from drying and cracking during storage and processing, improving combustion uniformity (cigarettes typically contain 1%-3% glycerin).

• Used as an adhesive and plasticizer in tobacco sheet production to enhance product flexibility.

2. Printing and Inks

• Humectant and leveling agent in inks to prevent ink from drying and caking during printing, improving image clarity (e.g., offset inks, water-based inks).

V. Chemical and Industrial Fields

1. Polyurethane Industry

• Serves as a polyol raw material in the synthesis of polyurethane foams and elastomers, influencing product hardness and elasticity (e.g., refrigerator insulation, shoe soles).

2. Coatings and Resins

• Humectant and film-forming aid in water-based coatings to prevent rapid drying and cracking (e.g., acrylic resin coatings).

• A key raw material in alkyd resin production, enhancing film gloss and flexibility.

3. Plastics and Rubber

• Plasticizer in plastic processing to reduce polymer melt viscosity and improve processability (e.g., PVC soft products).

• Softener in rubber products to enhance elasticity and delay aging (e.g., tires, rubber hoses).

4. Metal Processing

• Lubricant and rust inhibitor in cutting fluids and grinding fluids to reduce tool wear and protect metal surfaces (e.g., aluminum processing).

VI. Agriculture and Biotechnology

1. Feed Additives

• Acts as a humectant and energy source in livestock and poultry feed, improving feed palatability, especially for aquatic and ruminant feeds.

2. Plant Protection and Aquaculture

• Component of plant antifreeze to lower freezing point and prevent crop frost damage; additive in livestock drinking water to supplement energy.

3. Biofuels and Fermentation

• By-product of biodiesel production, which can be further processed into chemical raw materials such as propylene glycol and epichlorohydrin.

• Carbon source for microbial fermentation (e.g., production of probiotics, enzymes).

VII. Other Special Applications

1. Aerospace

• Component of aircraft hydraulic oils and brake fluids, utilizing its high boiling point and low freezing point (e.g., hydraulic systems in low-temperature environments).

2. Electronics Industry

• Cleaner and welding aid for electronic components, removing surface oil and preventing oxidation.

3. Military and Explosives

• Raw material for nitroglycerin, used in the production of explosives (e.g., dynamite) and propellants (requires special nitration treatment).

Safety and Regulations

• Safety: Glycerol is generally non-toxic to humans (ADI value "not specified," FDA-listed as GRAS), though high concentrations may cause mild skin irritation.

• Environmental Friendliness: Biodegradable and environmentally safe, widely used in green chemicals and sustainable material production.