Hydrogen sulfide (H2S) is a colorless and highly toxic acid gas. It is the simplest of sulfur hydride. It is an inorganic compound with no obvious odor at high concentration, a strong rotten egg smell at low concentration, and a sulfur smell at very low concentration.

Basic Information

Chinese name ：硫化氢

English name ：Hydrogen sulfide

Chemical formula : H2S

Molecular weight : 34.08

CAS : 7783-06-4

EINECS : 231-977-3

Melting point : -85.5 ℃

Boiling point : -60.4 ℃

Density ：1.54kg /m³

Appearance : Colorless , with rotten rotten egg like smell

UN : 1053

Class： 2.3+2.1

Hydrogen Sulfide Application

Hydrogen sulfide is a colorless gas with the odor of rotten eggs. Despite its toxicity, it has important applications in many fields.

 Industry Field

Metal smelting: Hydrogen sulfide can be used to selectively precipitate metal ions in the refining process of certain metal ores. For example, in the wet smelting of copper, lead, zinc and other metals, hydrogen sulfide is introduced into the solution containing metal ions, which can precipitate specific metals in the form of sulfide and separate them from other impurities, so as to achieve the purpose of purifying metals.

Chemical synthesis: it is an important raw material for the preparation of a variety of sulfides. For example, by reacting hydrogen sulfide with metal oxides or salts, zinc sulfide and cadmium sulfide can be prepared, which are widely used in electronic, optical materials and other fields. Zinc sulfide can be used as a substrate material for phosphors, and cadmium sulfide is often used to make optoelectronic components.

Petrochemical: In petroleum refining, the presence of hydrogen sulfide can be used as an indication of the decomposition of sulfur-containing compounds in crude oil. At the same time, refineries use hydrogen sulfide to react with lye to remove sulfide from oil, reducing the sulfur content of oil and producing clean fuel that meets environmental standards.

Field of Agriculture

Soil improvement: Low concentrations of hydrogen sulfide can regulate soil pH and microbial activity. In some acidic soils, an appropriate amount of hydrogen sulfide can promote the growth and reproduction of beneficial microorganisms in the soil, which help to decompose organic matter in the soil, release more nutrients, improve soil structure and improve soil fertility.

Plant growth regulation: It has been found that low doses of hydrogen sulfide can act as a signaling molecule, affecting the process of plant growth and development. It can promote seed germination, root growth and improve plant tolerance to stress (such as drought, high temperature, heavy metal stress, etc.).

Scientific Research Field

Biomedical research: Hydrogen sulfide has been found to be an endogenous gas signaling molecule, involved in a variety of physiological and pathological processes in the human body. In the cardiovascular system, it can regulate vascular tone and has the effect of vasodilation, which has potential research value for the prevention and treatment of cardiovascular diseases. In the nervous system, hydrogen sulfide may participate in the process of nerve signal transmission and neuroprotection, which provides a new idea for the treatment of nervous system diseases.

Analytical chemistry: Hydrogen sulfide is often used for qualitative analysis in analytical chemistry. The types of metal ions in the solution can be identified by observing the color, shape and other characteristics of sulfide precipitates generated by the reaction of hydrogen sulfide with different metal ions.

Storage and transportation of hydrogen sulfide

As a highly toxic and corrosive gas, the storage and transportation process of hydrogen sulfide needs to strictly follow safety regulations to prevent leakage and other safety accidents.

Storage

Storage environment: 

Hydrogen sulfide should be stored in a cool and well-ventilated special storage room, away from fire and heat source. Warehouse temperature should not exceed 30℃, relative humidity should not exceed 80%. Avoid direct sunlight, which may speed up the breakdown of hydrogen sulfide or trigger other chemical reactions. At the same time, the storage area should be stored separately from oxidant, acid, alkali and other substances, avoid mixed storage.

Storage Device:

Pressure vessels:   Special high-pressure cylinders are usually used to store hydrogen sulfide gas. These cylinders need to have good pressure resistance and are generally made of alloy steel that can resist hydrogen sulfide corrosion. Cylinders must pass strict pressure test and sealing test before use to ensure their safety and reliability.

Low temperature storage tank:   for large-scale storage of hydrogen sulfide, low temperature storage tank can be used. Storage can be greatly increased by cooling hydrogen sulfide below its boiling point (-60.3 ° C) so that it becomes a liquid for storage. Cryogenic tanks need to have good thermal insulation to reduce the incoming heat and maintain the liquid state of hydrogen sulfide. At the same time, the storage tank should be equipped with perfect safety devices, such as safety valves, liquid level meters, thermometers, etc., so as to monitor and control the storage status in real time.

 Transportation

Road transport:

Vehicle requirements: The vehicle for transporting hydrogen sulfide must be a special vehicle with hazardous chemical transportation qualification. The vehicle shall be equipped with fire and explosion-proof devices, such as flame arresters and electrostatic grounding devices, to prevent explosions caused by sparks during transportation. At the same time, the vehicle should be installed with an emergency cut-off device, so that the air source can be quickly cut off in case of emergency such as leakage.

Transport personnel: drivers and escorts must undergo professional training and obtain corresponding qualification certificates. They should be familiar with the nature, hazards and emergency treatment measures of hydrogen sulfide, and strictly abide by traffic rules and hazardous chemical transportation procedures during transportation.

Railway transportation:

Railway tank cars: Specially designed railway tank cars are used to transport hydrogen sulfide. The tank body of the tank truck should meet the relevant standards and have sufficient strength and tightness. In the process of loading and unloading, it should be carried out in strict accordance with the operating rules to ensure that the connection parts are firm and prevent leakage.

Transportation management: The railway department implements strict planning management and safety monitoring for the transportation of hydrogen sulfide. Relevant transportation procedures should be handled before transportation, and real-time tracking should be carried out during transportation to ensure transportation safety.

Marine transportation:

Ship requirements: The ship transporting hydrogen sulfide must be a chemical carrier conforming to the relevant regulations of the International Maritime Organization (IMO). Ships should have good ventilation systems to prevent the accumulation of hydrogen sulfide in the holds. At the same time, the ship should be equipped with perfect fire fighting equipment and leakage emergency treatment equipment.

Handling operations: When loading and unloading hydrogen sulfide, appropriate ports and handling equipment should be selected. In the process of loading and unloading, the flow speed should be strictly controlled to prevent electrostatic accidents caused by excessive flow speed. At the same time, pay close attention to the weather conditions and avoid loading and unloading operations under adverse weather conditions.

Transportation regulation: Marine hydrogen sulfide is subject to strict regulation by relevant international and domestic maritime authorities. During the transportation process, the ship should regularly report the transportation situation to the regulatory authorities to ensure that the whole transportation is under supervision.

Whether storing or transporting hydrogen sulfide, we must attach great importance to safety issues and strictly implement relevant safety standards and operating procedures to ensure the safety of personnel and the environment.