CN-117797858-B - Ni-Fe binary metal coal catalytic gasification catalyst and preparation method and application thereof

Abstract

The invention discloses a Ni-Fe binary metal coal catalytic gasification catalyst and a preparation method and application thereof, and belongs to the field of coal gasification. The invention aims to solve the technical problems that Ni catalyst is easy to sinter and sulfur poisoning under high temperature condition, so that the activity of the Ni catalyst is greatly reduced. The Ni and Fe in the catalyst of the invention are anchored on the HZSM5 molecular sieve in a physical adsorption mode and are highly dispersed on the surface of the HZSM5 molecular sieve, and are prepared by adopting an excessive impregnation method and roasting. According to the invention, the transverse etching characteristic of Ni and the vertical etching characteristic of Fe are coupled, the gasification etching process of the catalyst on coal is enhanced in the space direction, the carbon conversion rate is greatly improved, and an optimization thought is provided for the design of the coal catalytic gasification catalyst. Compared with the existing catalyst, the Ni-Fe binary metal catalyst has excellent catalytic activity and thermal stability, and the preparation method is simple, so that the catalyst becomes a coal catalytic gasification catalyst with great development potential.

Inventors

• LIU HUI
• LI RUIZHI
• ZOU YILE
• LIU JING
• WU CHENYAO

Assignees

• 哈尔滨工业大学

Dates

Publication Date

20260505

Application Date

20240122

Claims (5)

1. 1. The application of the Ni-Fe binary metal catalyst in coal gasification is characterized in that Ni and Fe in the catalyst are anchored on an HZSM5 molecular sieve through physical adsorption and are highly dispersed on the surface of the HZSM5 molecular sieve, wherein Ni accounts for 15-20% of the mass of the HZSM5 molecular sieve, fe accounts for 30-40% of the mass of the HZSM5 molecular sieve, and the catalyst is prepared according to the following steps: Step 1, dissolving Ni (NO 3 ) 2 ·6H 2 O and Fe (NO 3 ) 3 ·9H 2 O in deionized water to obtain a precursor solution; step 2, calcining the HZSM5 molecular sieve, and cooling to room temperature; step 3, dipping the calcined HZSM5 molecular sieve in a precursor solution by adopting an excessive dipping method, continuously stirring while heating, and then drying; step 4, roasting again, grinding and sieving to obtain the catalyst; In step 2, 2 h-3 h are calcined at 500-600 ℃.
2. 2. The use according to claim 1, wherein in step3 the impregnation temperature is 80 ℃ and the time is 1 h.
3. 3. The use according to claim 1, wherein in step 3, the drying is performed at a temperature of 110 ℃ to 120 ℃ of 12 h.
4. 4. The use according to claim 1, wherein in step 4, 3h to 4 h are calcined at 500 ℃ to 600 ℃.
5. 5. The use according to claim 1, wherein in step 4, a 120 mesh screen is passed.

Description

Ni-Fe binary metal coal catalytic gasification catalyst and preparation method and application thereof Technical Field The invention belongs to the technical field of coal gasification, and particularly relates to a Ni-Fe binary metal coal catalytic gasification catalyst and a preparation method and application thereof. Background The coal gasification technology is a clean coal technology, and is also a key core technology for developing coal-based chemical synthesis (ammonia, methanol, acetic acid, olefin and the like), coal-based liquid fuel synthesis (dimethyl ether, gasoline and the like), hydrogen production, integrated gasification combined cycle power generation (IGCC) and gasification combined fuel cell power generation (IGFC). The development of the poly-generation technology taking the coal gasification technology as the core has become a hot spot technology and an important development direction for efficiently and cleanly utilizing coal in various countries. The gasification process is a thermochemical process, and under the condition of high temperature, air, pure oxygen, steam or hydrogen and the like are used as gasification media, and solid fuel is converted into gas fuel through partial oxidation reaction. However, with conventional gasification techniques, there is a bottleneck in practical use because the required reaction temperature is high and more graphite-like carbon of low reactivity is produced at high temperature. The catalytic gasification technology has been widely studied in recent years because of its characteristics of low reaction temperature and high thermal efficiency in the reaction process. The metal catalyst accelerates the decomposition of the carbon-oxygen surface complex, improves the gasification reaction rate at a relatively low temperature, and is always a hot spot for catalytic gasification research. Under gasification conditions, coal and char can be converted to low activity graphite-like carbon, and metal etching of the graphite-like carbon is an essential process for catalytic gasification. The lateral etching capability and the vertical etching capability of different metals are different. From the aspect of the morphological characteristics of the gasified etched grooves, some metals can form deep grooves in the vertical direction of the graphite-like carbon surface, but the width of the grooves is smaller, and the grooves left by some metals are shallower but the width is larger, so that the catalytic performance of the catalyst is also provided with a larger promotion space when a single metal catalyst is used. The Ni catalyst is a common coal gasification catalyst, and is characterized by edge recession type etching with transverse etching characteristics in catalytic gasification, and higher catalytic activity in the process of catalytic gasification of coal, but the Ni catalyst is easy to sinter and poison sulfur under high temperature conditions, so that the activity of the Ni catalyst is greatly reduced, and the Ni catalyst is difficult to popularize in industry. Disclosure of Invention The invention provides a Ni-Fe binary metal coal catalytic gasification catalyst and a preparation method thereof, wherein the binary metal catalyst couples transverse etching of metal Ni and vertical etching direction characteristics of metal Fe, the transverse widening capability and vertical deep capability of the binary metal catalyst are complementary, and a gasification etching process is enhanced in a space direction, so that deep and wide etching grooves can be formed, and the carbon conversion rate is greatly improved. The Fe element is added into the Ni catalyst, so that the dispersibility of Ni phase particles is improved, and the sintering of the Ni catalyst at high temperature can be inhibited. The catalyst disclosed by the invention takes the HZSM5 molecular sieve with higher acidity as a carrier, so that the resistance of the Ni catalyst to sulfur poisoning is improved, meanwhile, the HZSM5 molecular sieve has larger specific surface area, larger loading amount of active substances in the catalyst, high thermal stability, high tolerance to sulfur and nitrogen compounds and easiness in regeneration are realized, and the catalyst is a good carrier of the Ni-Fe binary metal coal catalytic gasification catalyst. The invention adopts the following technical scheme: the invention aims to provide a Ni-Fe binary metal coal catalytic gasification catalyst, which is prepared by adopting an excessive impregnation method, wherein Ni and Fe in the catalyst are anchored on an HZSM5 molecular sieve in a physical adsorption mode and are highly dispersed on the surface of the molecular sieve. Wherein Ni accounts for 15-20% of the molecular sieve, and Fe accounts for 30-40% of the molecular sieve. The invention provides a preparation method of a Ni-Fe binary metal coal catalytic gasification catalyst, which is characterized by comprising the following steps: step 1, dis