Science and Education in Karakalpakstan issn 2181-9203 Science Magazine chief editor

 
 
 
 
 

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Science and Education in Karakalpakstan. 2023 №2/1 ISSN 2181-9203 
36 
UDC 66.074.371 
METHANE PURIFICATION METHODS FROM HYDROGEN SULFIDE AND 
MERCAPTANS
 
Makhmudov M.J.
1
, Adizov B.Z.
2
, Azimov S.T.
3
, Svaykosov S.O.
4
 
1
Bukhara institute of engineering and technology 
2
Institute of General and Inorganic Chemistry 
3
Karshi engineering economics institute 
4
Karakalpak State University named after Berdakh 
 
Summary:
 The main amount of sulfur-containing compounds from natural gas is removed 
at gas processing plants before being fed into main pipelines to prevent pipe corrosion and produce 
commercial sulfur. The reduction of the sulfur content to the required level is provided by the fine 
desulfurization unit located in the head part of the units. This article presents and analyzes modern 
methods of gas purification from hydrogen sulfide. 
Keywords:
 sulfur content, natural gas, gas purification, sulfur compounds, desulphurization
When RSH mercaptans interact with alkalis in the presence of O
2 
and CO
2
, which are 
always, albeit in small quantities, in gases, di- and polysulfides are formed, which are poorly 
soluble in the absorbent. Carbon sulphide neutral in nature, organic sulfides RSR' (and a number of 
other compounds) dissolve in these absorbents, although their sorption capacity is much less than 
that of RSH. The presence of CO 
2 
in gases above 0.1–0.3% leads to its preferential dissolution, 
significantly reducing the absorption of RSH. Natural gases tend to contain CO
2 
above 0.7%, which 
makes it difficult to use these methods for fine purification. The methods are also inefficient for 
purification from thiophene C
4
H
4
S and its derivatives. 
Of mono- and diethanolamine with various activating additives, such as N-
methylpyrrolidone-2, dipropanolamine, etc., are also widely used to remove acidic sulfurous 
substances. 
Adsorption methods have become widely used. They are based on the selective absorption 
(adsorption) of sulfur compounds by solid sorbents. As a rule, adsorption is carried out at a 
temperature of 20–50°C and elevated pressure, and regeneration (desorption) of a sorbent saturated 
with sulfurous substances is carried out at low pressure and a temperature of 100–350°C. For 
regeneration, any of the inert gases, low-sulfur natural or petroleum gas, water vapor, etc. are 
passed through the adsorbent layer [1-3]. 
In some cases, catalytic reactions proceed simultaneously with adsorption, as a result of 
which sulfurous substances are converted into elemental sulfur, which is recovered during 
regeneration and then used. 
As an adsorbent, activated carbon of the AR-3, SKT-1 and other brands, as well as coal with 
alkali additions, is used. At the same time, along with purification from sulfurous substances, 
benzene and toluene are also extracted from gases, which are then released during regeneration. 
Molecular sieves (zeolites) of the CaA and, especially, NaX grades have become widely 
used as adsorbents for the purification of polysulfurous natural and petroleum gases. Their 
adsorption capacity largely depends on the content of H
2
O, CO
2 
and higher hydrocarbons in gases, 
operating conditions and degree of purification and ranges from 2 to 18% [4]. 
The presence of heavy hydrocarbon vapors in the gas has a significant effect on the capacity 
of zeolites for sulfur compounds. According to the degree of sorption on zeolites, the compounds 
included in the composition of natural gas can be arranged in a row: