Product Name: Propane

CAS：74-98-6

Molecular formula：C3H8

Molecular weight：44.1

EINECS：200-827-9

Overview

Propane is a colorless, odorless, flammable gaseous alkane containing 3 carbon atoms. It is heavier than air and often stays at low altitudes. It can form explosive mixtures with air. The explosion limit is 2.4% to 9.5% (volume). It is easily soluble in ether, alcohol, benzene and chloroform, slightly soluble in acetone, and insoluble in water. However, it is easy to form solid hydrates with water at low temperatures, causing blockage of natural gas pipelines. It is easy to liquefy under pressure, with a critical temperature of 96.8℃ and a critical pressure of 4.24MPa. It is chemically inactive, but can undergo halogenation and other reactions. It exists in petroleum pyrolysis gas and natural gas. Industrially, propane can be separated from oilfield gas and cracking gas. It can be used as a raw material for the production of ethylene and propylene or a solvent in the oil refining industry; a mixture of propane, butane and a small amount of ethane can be used as a civilian fuel after liquefaction, namely liquefied petroleum gas.

Propane Properties

Chemical properties

Colorless, odorless, flammable and explosive gas. It is easily liquefied under pressure at room temperature. Boiling point is about -42℃. Solubility (all V/V): 17.8℃, 100 water: 6.5; 16.6℃, 100 anhydrous ethanol: 790, 100 ether: 926; 21.6℃, 100 chloroform: 1299. The vapor pressure at 21℃ is about 1.37MPa.

Chemical reaction The chemical reaction formula for complete combustion of propane in pure oxygen is: 

C3H8+5O2=3CO2+4H2O+2221.5kl/mol From the above formula, we can know that the theoretical oxygen consumption for complete combustion of 1 volume of propane is 5 volumes. When the propane flame burns in the air, the actual oxygen consumption is 3.5 volumes to form a neutral flame, and the flame temperature is 2520℃ (about 580℃ lower than acetylene). The maximum temperature of the oxidizing flame is about 2700℃ (about 600℃ lower than acetylene). The oxygen consumption is higher than acetylene.

Combustion calorific value The combustion calorific value of propane (standard state) is high calorific value: 101266kJ/m3, low calorific value: 93240kJ/m3. The combustion speed of propane is: 2m/s (in pure oxygen), 1.5m/s (in air). The total calorific value is higher than that of acetylene, but the combustion heat per gram molecule is lower than that of acetylene, the flame temperature is lower, and the flame heat is more dispersed.

Uses

1. Alkanes are mainly found in oilfield gas, natural gas, and refinery gas. They are used to make ethylene, propylene, oxygen-containing compounds, and primary nitroalkanes. They may come into contact with them during production or application. They are also commonly used as fuel for barbecues, portable stoves, and motor vehicles.

2. Aerosols; inflators.

3. Used as organic chemical raw materials, solvents, and fuels, etc.

4. Mainly used in petrochemicals, environmental protection, and scientific research, etc.

5. In addition to being used as fuel and refrigerant, they are mainly used as raw materials for cracking ethylene and propylene, as well as for making acrylonitrile, nitropropane, and perchloroethylene; as solvents for deasphalting and desulfurization in refineries, etc.

Production method

1. The crude propane obtained from the propylene distillation tower kettle of the cracking unit is refined by a propane distillation tower to obtain propane with a purity of 90%, which is cooled by the tower kettle and sent to a propane storage tank. The finished propane can also be obtained by separating the catalytic cracking gas.

2. It is obtained by distilling natural gas and absorbing it with oil or freezing it.