JPH07118668A - Method for removing sulfur compound in sulfur-containing gas - Google Patents

Abstract

PURPOSE:To provide a method for removing sulfur compounds in a sulfur- containing gas in which the sulfur compounds such as hydrogen sulfide, mercaptans, sulfides or organosulfur compounds can extremely efficiently be captured and removed at ordinary temperature under ordinary pressure. CONSTITUTION:This method for removing sulfur compounds in a sulfur- containing gas is to add, mix or bring the gas containing at least one of sulfur compounds selected from the group consisting of hydrogen sulfide, mercaptans, sulfides and other organosulfur compounds to, with or into contact with ozone gas, bring the resultant mixed gas into contact with an adsorbent composed of zeolite and capture the sulfur compounds in the adsorbent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fuel gas for fuel cells, natural gas, city gas, LPG, naphtha, various process gases, etc., containing a sulfur compound such as hydrogen sulfide, mercaptans and sulfides, or The present invention relates to a method for removing sulfur compounds in those mixed gases.

[0002]

2. Description of the Related Art A conventional method for removing a sulfur compound in a gas containing a sulfur compound and containing hydrocarbon as a main component is, for example, adding hydrogen to the gas stream to obtain 300
A so-called hydrodesulfurization method is known in which a sulfur compound is modified into hydrogen sulfide by bringing it into contact with a Ni-Mo-based or Co-Mo-based catalyst at a high temperature of not lower than 0 ° C, and this is captured by zinc oxide. This method has problems that a hydrogen-containing gas and equipment for supplying the same are required, a high temperature of 300 to 400 ° C. is required, and handling of the catalyst accompanying the catalytic reaction becomes complicated. is there.

As a desulfurization method for the above-mentioned various sulfur compound-containing gases or a method for removing sulfur-containing odorous and harmful components in these gases, a method using activated carbon or the like as an adsorbent is known. It is effective in removing hydrogen and carbonyl sulfide, but not enough in removing organic sulfur compounds.

For example, in JP-A-61-35821, hydrogen sulfide is removed by an adsorbent in which one or more oxides of Fe, Co, Mn and Mo are supported on a silica-alumina carrier containing zeolite. However, by heating and regenerating this adsorbent in the presence of oxygen, there is disclosed a method for treating a hydrogen sulfide-containing gas in which regeneration is efficiently carried out at a low temperature, but sulfur compounds other than hydrogen sulfide, particularly organic sulfur compounds, are disclosed. It does not describe a method for removing the sulfur compounds that are simultaneously captured.

Further, as a method for removing sulfur compounds from a coal carbonization gas or a gas produced by the reaction of petroleum or coal with steam and / or an oxygen-containing gas, a method of capturing the gas in a hydrous iron oxide at room temperature and Although methods for capturing iron oxides at high temperature are known, these methods can mainly capture hydrogen sulfide, but have a problem that it is difficult to remove the organic sulfur compound.

As a method for removing acidic sulfur compounds such as hydrogen sulfide in the gas produced by the reaction of the above-mentioned petroleum or coal with steam and / or oxygen-containing gas, a solution of alkali such as caustic potash or monoethanolamine, etc. Although a method of absorbing it in a solution of the amine compound is known, it is not suitable as a method for removing an organic sulfur compound such as mercaptans.

According to the present invention, a sulfur compound in a gas containing a sulfur compound such as hydrogen sulfide, mercaptans, sulfides and organic sulfur compounds can be captured very efficiently at room temperature and atmospheric pressure.
It is an object of the present invention to provide a method for removing a sulfur compound in a sulfur-containing gas that can be removed. The present invention relates to fuel gas for fuel cells, natural gas, city gas, LP
G, naphtha, or sulfur gas in gases such as natural gas, petroleum such as LPG and naphtha, various product gases obtained by processing coal, etc. is extremely efficiently trapped under normal temperature and pressure.
It is an object of the present invention to provide a method for removing a sulfur compound in a sulfur-containing gas that can be removed. INDUSTRIAL APPLICABILITY The present invention relates to a fuel cell and purification of a raw material gas used for producing hydrogen or a synthetic raw material gas, purification of a produced gas produced from natural gas, petroleum and coal, deodorization of odorous gas such as city gas, It is an object of the present invention to provide a method for removing a sulfur compound from a sulfur-containing gas, which enables efficient purification, deodorization, and detoxification of the sulfur-containing gas under normal temperature and normal pressure.

[0008]

The present invention relates to hydrogen sulfide,
Ozone gas is added, mixed and contacted with a gas containing at least one sulfur compound selected from the group consisting of mercaptans, sulfides and other organic sulfur compounds, and then the mixed gas is adsorbent made of zeolite. The present invention provides a method for removing a sulfur compound in a sulfur-containing gas, which comprises contacting the adsorbent with the sulfur compound to capture the sulfur compound.

Sulfur compounds captured and removed by the method of the present invention include mercaptans such as hydrogen sulfide, methyl mercaptan and t-butyl mercaptan, sulfides such as dimethyl sulfide, carbon disulfide and carbonyl sulfide, and thiophene. Other organic sulfur compounds are included.

As the gas containing a sulfur compound to be treated by the method of the present invention, for example, fuel gas for fuel cell, natural gas, city gas, LPG, naphtha, or natural gas,
Examples include petroleum such as LPG and naphtha, and various produced gases obtained by treating coal and the like.

The method of the present invention is applied to a fuel cell and purification of a raw material gas used for producing hydrogen or a synthetic raw material gas, purification of a product gas produced from natural gas, petroleum and coal, and an odorous gas such as city gas. It is applied to efficiently carry out deodorization, purification of other gases, deodorization, and detoxification.

As the ozone gas used in the method of the present invention, for example, gaseous ozone generated by a silent discharge device or the like can be used.

The addition, mixing, and contact of ozone gas with the sulfur-containing gas in the method of the present invention are carried out under normal temperature and normal pressure conditions.

In the method of the present invention, the mixed gas obtained by adding, mixing and contacting ozone gas with the sulfur-containing gas and the adsorbent composed of zeolite are contacted with, for example, a packed bed filled with the mixed gas. It is carried out under normal pressure by flowing and contacting at a temperature of 50 ° C. or lower, preferably room temperature.

In the method of the present invention, the amount of ozone gas added to the sulfur-containing gas is 0.1% by volume or more, preferably 3% by volume or more, more preferably 5% by volume or more in the sulfur-containing gas. However, even if the amount added exceeds 5% by volume, the breakthrough time does not increase and the saturation value remains substantially constant. This means that ozone gas
This means that it is not necessary to strictly control the addition amount when adding more than the volume%. Especially the breakthrough time
Under a constant gas flow rate condition, the amount of the sulfur compound in the adsorbent layer outlet gas after the gas starts flowing through the adsorbent layer is
The time required to reach 20% of the concentration in the inlet gas,
There is a correlation with the adsorption rate of sulfur compounds (the amount of sulfur in the sulfur compounds trapped in the adsorbent, expressed as a percentage (%) relative to the weight of the adsorbent), and serves as a measure of the adsorption performance of the adsorbent. It will be.

The zeolite used as the adsorbent of the present invention is not particularly limited as long as it has sufficient trapping performance under the above-mentioned conditions. For example, zeolite A, zeolite X, zeolite Y, zeolite L, Molecular sieve zeolites such as zeolite Q, ZSM-5, chabazite, erionite, offretite, mordenite, ferrierite and clinotylolite are preferred.

[0017]

According to the present invention, firstly, a sulfur compound in a gas containing a sulfur compound such as hydrogen sulfide, mercaptans, sulfides, and organic sulfur compounds can be captured very efficiently at room temperature and atmospheric pressure. Can be removed. According to the present invention, secondly, fuel gas for fuel cell, natural gas, city gas,
Sulfur compounds in gases such as LPG, naphtha, or petroleum such as natural gas, LPG, naphtha, and various product gases obtained by treating coal can be captured and removed extremely efficiently under normal temperature and pressure. . According to the present invention, thirdly, the refining of the raw material gas used for producing the fuel cell and hydrogen or the synthetic raw material gas, the refining of the produced gas produced from natural gas, petroleum and coal, the odor of city gas, etc. Deodorization of gas, purification and deodorization of other sulfur compound-containing gas,
The detoxification can be efficiently performed at room temperature and atmospheric pressure.

[0018]

The present invention will be described in more detail with reference to the following examples and comparative examples.

Example 1 Ozone gas was added to, mixed with, and contacted with nitrogen gas containing 20 ppm of dimethyl sulfide at a concentration of 5% by volume, then a gas flow rate of 50 cm / sec, a gas flow rate of 1130 l / hr, a temperature of 26 ° C. and Pelletized molecular sieve 13X as adsorbent under atmospheric pressure
(Molecular sieve zeolite manufactured by Toyo CCI Co., Ltd.)
The sample was passed through a cylindrical filling container filled with 100 g to carry out a trapping experiment to determine the breakthrough time and the adsorption rate. The results obtained are shown in Table 1. In Table 1, the adsorption rate indicates the weight% when the weight of the adsorbed sulfur compound is converted into the weight of sulfur with respect to the weight of the adsorbent (the same applies hereinafter).

Example 2 The same experiment as in Example 1 was carried out except that spherical molecular sieves 13X (trade name of molecular sieve zeolite manufactured by Toyo CCI Co., Ltd.) were used in place of the pellet-shaped molecular sieves 13X of Example 1. The results obtained are shown in Table 1.

Comparative Example 1 The same experiment as in Example 1 was carried out except that coconut shell activated carbon (manufactured by Takeda Pharmaceutical Co., Ltd.) was used in place of the adsorbent of Example 1. The results are shown in Table 1.

Comparative Example 2 The same experiment as in Example 1 was carried out except that the activated carbon of coal type (manufactured by Takeda Pharmaceutical Co., Ltd.) was used in place of the adsorbent of Example 1. The results obtained are shown in Table 1.

Example 3 The same experiment as in Example 2 was carried out except that nitrogen gas containing 20 ppm of hydrogen sulfide was used instead of dimethyl sulfide. The results obtained are shown in Table 1.

EXAMPLE 4 Nitrogen gas containing 20 ppm of tertiary butyl mercaptan was used instead of dimethyl sulfide,
The same experiment as in Example 2 was performed. The results obtained are shown in Table 1.
Shown in.

Comparative Example 3 The same experiment as in Example 2 was carried out except that oxygen was added instead of ozone gas. The results obtained are shown in Table 1.

Example 5 The same experiment as in Example 1 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Example 6 The same experiment as in Example 2 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Example 7 The same experiment as in Example 3 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Example 8 The same experiment as in Example 4 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Comparative Example 4 The same experiment as in Comparative Example 1 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Comparative Example 5 The same experiment as in Comparative Example 2 was conducted except that the ozone gas concentration was changed as shown in Table 2. The obtained results are shown in Table 2.

Comparative Example 6 Comparative Example 3 except that the oxygen concentration was changed as shown in Table 2.
The same experiment was performed. The obtained results are shown in Table 2.

[0033]

[Table 1]

[0034]

[Table 2]

Claims (1)

[Claims] 1. An ozone gas is added, mixed and contacted with a gas containing at least one sulfur compound selected from the group consisting of hydrogen sulfide, mercaptans, sulfides and other organic sulfur compounds, and then the ozone gas is added. A method for removing a sulfur compound from a sulfur-containing gas, which comprises contacting a mixed gas with an adsorbent made of zeolite so that the sulfur compound is captured by the adsorbent.