Catalysts having metal nano-particle catalyst supported on surface-treated natural cellulose fibers and preparation method thereof

Patent metadata

Field	Value
Publication number	US-9254483-B2
Application number	US-201314035194-A
Country	US
Kind code	B2
Filing date	Sep 24, 2013
Priority date	Nov 10, 2009
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

The present disclosure relates to a catalyst having metal catalyst nanoparticles supported on natural cellulose fibers and a method of preparing the same, whereby natural cellulose fibers are subjected to specific pretreatment to increase a surface area and form defects on the surface thereof and metal catalyst nanoparticles are then supported on the cellulose catalyst support in a highly dispersed state, thereby providing improved catalysis while allowing production of the catalyst at low cost. The catalyst may be utilized for various catalytic reactions.

First claim

What is claimed is:

1. A method of preparing a catalyst having metal catalyst nanoparticles supported on natural cellulose fibers, comprising:
(1) treating natural cellulose fibers with an electron beam by irradiating an electron beam of 10 to 500 kGy to the natural cellulose fibers;
(2) heat-treating the electron beam-treated natural cellulose fibers by cutting the electron beam treated natural cellulose fibers to a length of 1˜2 mm in a state of being impregnated in liquid nitrogen, and heat-treating natural cellulose fibers at 500 to 1500° C. at a rate of 5 to 20° C./min under in an atmosphere composed of a 1:1 mixture of hydrogen and nitrogen, the temperature being maintained at 500 to 1500° C. for 0.5 to 2 hours to carbonize the natural cellulose fibers;
(3) chemically treating the heat-treated natural cellulose fibers with an acidic solution to introduce an oxidizing group to a surface of the natural cellulose fibers to prepare a cellulose catalyst support, wherein chemically treating the natural cellulose fibers comprises sweeping the heat-treated natural cellulose fibers in 10-60 cycles at −0.15-1.3 V at a sweep rate of 50 mV/s, with the heat-treated natural cellulose fibers immersed in a 0.1-0.5 M aqueous sulfuric acid solution, followed by chemically treating the natural cellulose fibers, with the natural cellulose fibers immersed in a 30% nitric acid solution at 100-150° C.; and
(4) supporting metal catalyst nanoparticles directly on the surface of the cellulose catalyst support by chemical vapor deposition or impregnation,
wherein through a series of electron beam treatment, heat treatment, and chemical treatment, the cellulose catalyst support has pores with an inner channel size of up to 10 μm and a BET surface area of 230-383 m 2 /g, and functional groups introduced to a surface of the natural cellulose fibers.

2. The method of claim 1 , wherein the electron beam treatment of the natural cellulose fibers comprises irradiating an electron beam of 10 to 500 kGy to the natural cellulose fibers.

3. The method of claim 1 , wherein the heat treatment of the natural cellulose fibers comprises cutting the natural cellulose fibers to a length of 1˜2 mm, with the natural cellulose fibers impregnated in liquid nitrogen, and heat-treating natural cellulose fibers at 500˜1500° C. for 0.2 to 2 hours.

4. The method of claim 1 , further comprising: washing and drying the chemically treated natural cellulose fibers to prepare the cellulose catalyst support.

5. The method of claim 1 , wherein the oxidizing group introduced to the surface of the natural cellulose fibers comprises CO—, CH—, O—C═O, CO 2 , or CO 3 .

6. The method of claim 1 , wherein the metal catalyst nanoparticles supported on the cellulose catalyst support by the chemical deposition or impregnation comprise platinum particles, and a platinum precursor for supporting the platinum particles on the cellulose catalyst support is selected from the group consisting of MeCpPtMe 3 , Pt(Me) 3 (Cp), Pt(Tfacac) 2 , Pt(Me)(CO)(Cp), Pt(Me) 2 (COD), [PtMe 3 (acac)] 2 , PtCl 2 (CO) 2 , Pt(PF 3 ) 4 , Pt(acac) 2 , and Pt(C 2 H 4 ) 3 .

7. The method of claim 1 , wherein the metal catalyst nanoparticles supported on the cellulose catalyst support by the chemical deposition or impregnation comprise nickel particles, and a nickel precursor for supporting the nickel particles on the cellulose catalyst support is nickel nitrate (Ni(NO 3 ) 2 ) or nickel carbonyl (Ni(CO) 4 ).

8. The method of claim 1 , wherein the metal catalyst nanoparticles supported on the cellulose catalyst support by the chemical deposition or impregnation comprise cobalt particles, and a cobalt precursor for supporting the cobalt particles on the cellulose catalyst support is Co(CO) 3 NO or Co(NO 3 ) 2 .

9. The method of claim 1 , wherein the metal catalyst nanoparticles supported on the cellulose catalyst support by the chemical deposition or impregnation comprise molybdenum particles, and a molybdenum precursor for supporting the molybdenum particles on the cellulose catalyst support is Mo(CO) 6 .

10. The method of claim 1 , wherein the supporting the metal catalyst nanoparticles on the cellulose catalyst support by the chemical vapor deposition comprises removing impurities from within a quartz tube by placing the prepared cellulose catalyst support at a center of the quartz tube and maintaining the quartz tube at a pressure of 6˜10 Torr at 110˜120° C. for 30˜120 minutes; elevating an internal temperature of the quartz tube having the cellulose catalyst support therein to 80˜300° C.; and supplying a. gaseous metal precursor into the quartz tube under vacuum after a target reaction temperature is reached, thereby allowing the metal catalyst nanoparticles to be supported on the cellulose catalyst support.

11. The method of claim 1 , wherein the supporting the metal catalyst nanoparticles on the cellulose catalyst support by the impregnation comprises depositing the prepared cellulose catalyst support in an aqueous solution of a metal precursor, ultrasonicating the cellulose catalyst support, drying the cellulose catalyst support, and burning the cellulose catalyst support in nitrogen atmosphere.

Assignees

• Korea Energy Research Inst

Inventors

• Kim Hee Yeon
• Jeong Nam Jo
• Han Seong Ok

Classifications

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J31/06

  containing polymers {(organometallic polymers B01J31/123; polymer-bound organometallic complexes B01J31/165; coordination polymers B01J31/1691)} · CPC title

• B01J23/75

  Cobalt · CPC title

• C10G2300/70

  Catalyst aspects · CPC title

• C01B2203/1052

  Nickel or cobalt catalysts · CPC title