JPS60156548A - Collecting agent of carbon monoxide and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a CO collecting agent having excellent CO collecting performance by exchanging Na of ZSM-5 type zeolite wherein alumina per silica by molar ratio is small for Cu ion and heating the zeolite under CO atmosphere. CONSTITUTION:Na of ZSM-5 type zeolite wherein alumina per silica by molar ratio is <=19 is exchanged for Cu ion and thereafter the zeolite is heated at 150-500 deg.C under the CO atmosphere to obtain copper ( I ) type zeolite. The zeolite has more excellent collecting performance for CO than conventional performance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a carbon monoxide scavenger in which zeolite is specially treated.

Carbon monoxide (CO) has recently received renewed attention as a raw material gas in synthetic chemistry. For example, Odium (
Using old 1) as a catalyst, acetic acid is synthesized by reaction with methanol, or ethylene glycol is synthesized by reaction with hydrogen. Furthermore, C can be used as a raw material for the synthesis of oxalic acid, formic acid, etc.
O is used. Acetic acid and silicic acid are already produced on an industrial scale and are used as a CO source by gasifying heavy oil. Separation methods for obtaining CO from a gas containing CO as a raw material for these processes include a cryogenic separation method, a liquid preparation washing method, a CO3ORB method, a metal carbonyl method, and an adsorption separation method.

The cryogenic separation method involves liquefying and separating CO through low-humidity distillation, which requires excessive equipment.If the product CO is of high purity,
It has the disadvantage of low recovery rate. In particular, it is said that the practical application of gas processing in which N2 coexists is extremely difficult because the boiling points of these gases are close to each other. The liquid preparation cleaning method is used in the CO removal process of ammonia synthesis raw material gas purification.
Since complex salts such as CO are formed, high selectivity for CO is achieved. Q k'+ can be done.

However, this method is complicated to operate and has practical problems such as the need for steam to regenerate the absorption liquid. C
The 08ORB method utilizes a reaction in which a coordination compound of copper, aluminum tetrachloride, and toluene forms a chain with CO at room temperature and releases CO at high temperature.It has high CO selectivity and is suitable for recovering high-purity CO. Are suitable. However, this method has the same disadvantage as the liquid preparation cleaning method in that it requires a large amount of steam to regenerate the absorption liquid.

In the metal carbonyl method, a metal such as Ni, Fe, or H is brought into contact with CO in an active state to generate a carbonyl compound, and after the carbonyl compound is separated, it is heated to a temperature higher than its decomposition temperature to separate it into co and the metal.

For example, gaseous nickel carbonyl (Ni(CO),i) at 45-50 °C by contact of the active side with CO
can be obtained. It is necessary to separate Ni (CO) 4 from coexisting components, and separation methods include separating it in a gaseous state using a separation membrane, or liquefying it and extracting it.

The separation membrane needs to be selected depending on the types of coexisting components (fa), but in general, it is not a very complicated process since the separation is from gas molecules smaller than Ni (CO) 4. When (CO) 4 is thermally decomposed at 200° C., it becomes co and Xi in an active state.

Although the co-selectivity of the carbonylation step in this method is high,
The efficiency of the subsequent membrane separation is low, so it cannot necessarily be said to be a preferable method.

Adsorption separation method has been used as a technology to remove CO during hydrogen production, especially in PSA (Pres
A component separation process that does not require heating, called the ser swing absorption method, has already been used in many devices.

For example, CO along with methane and CO2 is extracted from hydrogen streams such as ethylene plant off gas and steelworks coke oven gas.
is removed to produce high-purity hydrogen.

The gases used for these raw materials generally contain impurities.

c contained in small amounts, for example in coke oven gas.

is 7-8v01%. The adsorbent used here is generally ion-exchanged type A zeolite with Ca ions.
Zeolite is called type A and is used in pellet form. This material has an adsorption capacity for CO, but at the same time it adsorbs I20, Co2, CI+4, etc.

When using zeolite 5A to obtain non-adsorbable components such as hydrogen or poorly adsorbable components as products, CO is an impurity and other impurities such as I20, CO2, CI
It can be co-adsorbed onto zeolite 5A together with 4 and the like and discharged outside the system in the regeneration process.

However, when recovering adsorbed CO as a product gas, other adsorbent components, such as N2, CH, CO,
1120 etc. in the adsorbent is not preferable. When CO is desorbed by reducing pressure or heating, simultaneous desorption of these co-adsorbed components occurs, and the recovered CO
This is because it causes a decrease in purity.

Therefore, it is preferable that the CO separation and recovery agent is selected only for CO and has a large capture capacity.

As a zeolite adsorbent with high selectivity for CO, its physical properties and performance are disclosed in US Pat. No. 4,019,879. According to this, copper ('II) ions are exchange introduced into zeolite with a silica to alumina molar ratio (hereinafter referred to as Capan ratio) of 20 to 200, and heated in a CO stream containing water vapor to form a copper (1) type zeolite. I got this, and I decided to use it as Keikisho II! (activated) and used as a CO adsorbent. For example, Cu with a 99% exchange rate to ZSN-5 with a Capan ratio of 46.
ion A was introduced, subjected to reduction treatment with moist CO, then degassed under vacuum at 100°C, and subsequently measured the activated 41co adsorption equilibrium at 300°C.
2wt% CO is obtained in HD. The inventors discovered that CO
As a result of searching for an adsorbent with a larger trapping capacity, it was found that by replacing ZSH-5 type zeolites 1~ with a low Capan ratio with Cu(1) type, it was possible to have superior CO trapping ability that exceeds conventional performance. I found out.

The zeolite that can be used in the present invention is ZSH-5 type zeolite, which can be synthesized, for example, by the method described in Japanese Patent Application No. 57-146,911. It is also possible to use the method described in US Pat. No. 3,702,886.

It is said that the ZSH-5 type zeolite synthesized by these methods can have a Capan ratio of 10 to 100, but in the conventional technology, the Kuipan ratio of synthetic crystals is determined by the blending ratio of raw materials, and the Capan ratio is 15 or less. No synthesis example has been found, and it has been said that a capan ratio of 20 is essentially the lower limit for synthesis.

However, as in the preferred embodiments, for example, by contacting zeolites 1~ with an alkali, Z with a Capan ratio of less than 20 can be obtained.
SH-5 type zeolite was prepared, and after contacting it with a solution containing copper (11) ions to form Cu2+-ZSH-5 type, it was subjected to reduction treatment at 150 to 500°C with a CO gas stream to form Cl''-ZSH- The type 5 has a capan ratio of 2
It has been found that ZSH-5 type CO adsorbent exhibits better performance than ZSH-5 type CO adsorbent.

ZSH-5 type zeolite, which has a relatively high Capan ratio, has a ratio of 1
The same ratio is reduced by contacting with an alkali (e.g. alkali hydroxide) solution of x~50%.

The solution containing copper (II) used in the present invention is, for example, an aqueous solution of copper nitrate, copper acetate, or copper sulfate.

The ZSM-5 type zeolite ion-exchanged with copper(II) was separated, washed with water, dried, and then heated for 15 hours in a carbon monoxide atmosphere.
It is heated at 0 to 500°C to reduce copper (II) and use it as a CO scavenger.

The thus obtained zeolite scavenger with a low Capan ratio has a higher CO capture ability than conventional ones with the same low ratio.

Examples are shown below.

Example 1 (Capan ratio reduction treatment) ZSH-5 type zeolite with a Capan ratio of 20.6 was
0, poured into a 5X NaOH aqueous solution, and maintained at 30°C.

After stirring for 75 hours, it was filtered, and 60° C. pure water was sprinkled on the cake on the Metsche until the pH of the filtrate reached 9.

After drying at 100° C. for 2 hours, component analysis was performed.

The Capan ratio was 12.6. Furthermore, the X-ray diffraction pattern of Cu- due to alpha rays was observed, and the reflection peak intensity was sufficiently large, indicating that the crystal structure was stably maintained.

(Preparation of Cu-ZSH-5 type zeolite) The ZSH-5 type zeolite with a Capan ratio of 12.6 obtained by the above treatment contains Na as a cation.

10 g of this was collected and poured into a 1N copper nitrate aqueous solution, pH was observed while stirring, and pl+ was maintained at 4 with acetic acid. After stirring at 60°C for 2 hours, filter, wash with water, and heat to 100°C.
After drying the cake, compositional analysis was performed.

The CU ion exchange rate of the obtained cake ZSN-5 type zealite was 97% (3% Na + ), and it had a pale blue color.

Next, 100cc of this Cu-ZSH-5 type zeolite
/sin of CO for 6 hours after heating to 3000 °C.
Cooled to air temperature in an O stream. This powder sample was decolorized and had a white color. The reduction of Cu+ to Cu+ by ESR and the maintenance of the crystal structure by the X-ray diffraction pattern (Figure 1) were confirmed.

(Evaluation of co-adsorption performance 1i11i) After vacuum degassing the CO+-ZSH-5 type zeolite at 350°C for 2 hours, it was kept at 30°C and the amount of CO adsorbed was measured. At 30°C, 150 ivol of CO was captured.

Separately, 30% of Cu”, -ZSH-5 type zeolite was added.
C. and relative humidity [180%] for 16 hours, and an increase in weight was observed.

The water content was 11.5wL%. Also, 30℃, 76
COW at 0 m19 was 3.9 wt%.

Example 2 Capan ratio reduction treatment conditions: 5% to 8% Na011 aqueous solution
By contacting at 0°C for 55 hours, the Capan ratio was 20.
．． 6 was changed to 7.2, and C was processed in the same manner as in Example 1.
u”-ZSH-5 type zeolite was obtained. CO absorption WQ was 3
It was 1.08 vaol/<+ at 0°C and 150ml/g.

Comparative example: ZSH-5 type zeolite with different Capan ratio and Cu2”
-1'on was removed and reduced by CO airflow,
A Cu'' type zeolite was prepared. Results of measurement of CO neck ω gave the results shown in the table of the method.

Capan ratio Cu2+ exchange rate CO adsorption amount *25.2
99% 0.42mn+ol/g49.8 97% 0
．． 22 pairs ■l/g* 30 C, 150mm 11g Capan ratio 12.6 (Example 1) 7.2 (Example 2)
It can be seen that the performance is extremely inferior to that of CO.

[Brief explanation of the drawing]

Figure-1 shows Cu+-15H-5 used in the embodiment of the present invention.
The X-ray diffraction pattern of type zeolite is shown. Patent Applicant Toyo Bottatsu Kogyo Co., Ltd. Procedural Amendment No. 1 May 18, 1859 Director of the Patent Office Kazuo Wakasugi 1 Display of Case 1989 Patent Application No. 1203+ 2 Name of Invention Carbon monoxide scavenger and the person making the 6th amendment to the manufacturing method Representative: Higashi Morishima Date of the 4th amendment order: April 4, 1980 (Shipping date: April 24, 1980) 5. Specification subject to amendment 6. Description of contents of amendment 6 Engraving (no change in content) Procedural amendments Commissioner of the Patent Office Gakudono Shiga September 10, 1980 1. Indication of the incident 1982 Patent Application No. 12033 2. Name of the invention Carbon monoxide scavenger and its manufacturing method 3.Relationship with the case of the person who carried out pressure compensation Special 8!1 Applicant Address 1, Oaza Tomi (14!i60, Shinnanyo City, 746 Yamal) Prefecture
Address 4, number of inventions added by 119 due to amendment O specification
Detailed Description of the Invention Column 7, Contents of Amendment 1) Before the Specification The scope of the claims is corrected as shown in the attached sheet. 2) Page 9, line 12 of the specification “150n+mol J at r 150mm 11g 0
．． Corrected to 94111nIO+. 8. Attached sheet with list of attached documents 1 attached sheet [2. Claim 1: A carbon monoxide scavenger with a silica to aluminization ratio of 19 or less and containing copper ions. 2. Copper ion-exchanged ZSH-5 type L olide with a silica to alumina ratio of 19 or less under a carbon monoxide scavenger at 150%
A method for producing a carbon monoxide scavenger, which comprises heating at ~500°C. ” The above amendments have been made by the Commissioner of the Japan Patent Office, Gakudono Shiga, September 12, 1980. 1. Indication of the case: Patent Application No. 12033 of 1982. 2. Name of the invention: carbon monoxide scavenger and its manufacturing method. 3. Amendments are made. Relationship with the Naichi case Patent applicant address: 4560-4 Tomita, Shinnanyo City, Yamaro Prefecture, 746
Number of inventions increased by amendment 0 5, Date of amendment order Voluntary amendment 6, Subject of amendment: t~Zeng Specification Column 7 for detailed explanation of the invention, Contents of amendment

Claims (1)

[Claims] 1. A carbon monoxide scavenger having a silica to alumina ratio of 19 or less and containing copper ions. 2. A copper ion-exchanged ZSH-type zeolite having a silica to alumina ratio of 19 or less Carbon monoxide scavenger under 150
A method for producing a carbon monoxide scavenger characterized by heating at ~500°C