CN102580782A

CN102580782A - Preparation Method of Magnetic Catalyst TiO2/PPY/Fe3O4

Info

Publication number: CN102580782A
Application number: CN2012100048548A
Authority: CN
Inventors: 任学昌; 王静; 念娟妮; 王雪娇; 王拯; 刘鹏宇; 常青
Original assignee: Lanzhou Jiaotong University
Current assignee: Lanzhou Jiaotong University
Priority date: 2012-01-09
Filing date: 2012-01-09
Publication date: 2012-07-18

Abstract

本发明涉及一种磁载催化剂TiO₂/PPY/Fe₃O₄的制备方法，该方法包括以下步骤：(1)制备纳米Fe₃O₄粒子；(2)制备磁流体PPY/Fe₃O₄；(3)TiO₂/PPY/Fe₃O₄催化剂的制备：①将无水乙醇与钛酸四正丁酯混合均匀后，得到溶液A；②在磁流体PPY/Fe₃O₄中加入溶液A，经磁力搅拌后加入蒸馏水，并搅拌直至钛酸四正丁酯完全水解，此时TiO₂包覆在PPY/Fe₃O₄上；再用冰醋酸调节其pH值，得到混合液；将混合液放入水热反应釜中，再把水热反应釜放入马弗炉中加热，之后常温冷却并依次用无水乙醇和蒸馏水反复洗涤数次，直到没有异味，再经烘干、研磨、过筛，即得磁载催化剂TiO₂/PPY/Fe₃O₄。本发明所得产物能有效提高催化活性和回收性能。The invention relates to a method for preparing a magnetic-supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ , the method comprising the following steps: (1) preparing nanometer Fe ₃ O ₄ particles; (2) preparing magnetic fluid PPY/Fe ₃ O ₄ ; (3) Preparation of TiO ₂ /PPY/Fe ₃ O ₄ catalyst: ①After mixing absolute ethanol and tetra-n-butyl titanate evenly, a solution A is obtained; ②Add the solution to the magnetic fluid PPY/Fe ₃ O ₄ A, add distilled water after magnetic stirring, and stir until tetra-n-butyl titanate is completely hydrolyzed, at this time TiO ₂ is coated on PPY/Fe ₃ O ₄ ; then adjust its pH value with glacial acetic acid to obtain a mixed solution; Put the mixed solution into the hydrothermal reaction kettle, then put the hydrothermal reaction kettle into the muffle furnace to heat, then cool it at room temperature and wash it repeatedly with absolute ethanol and distilled water for several times until there is no peculiar smell, then dry and grind and sieving to obtain the magnetically supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ . The product obtained in the invention can effectively improve catalytic activity and recovery performance.

Description

Magnetic carried catalyst TiO 2/ PPY/Fe 3O 4The preparation method

Technical field

The present invention relates to the photocatalyst technology field, relate in particular to magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method.

Background technology

Since excellent photocatalysis property, TiO ₂The photocatalytic degradation pollutant has caused both at home and abroad extensively scholar's concern.The powdered form photochemical catalyst exists factors such as separation difficulty, and the characteristics that can not reuse have the scholar with TiO ₂Load on block materials (glass, pottery, metal etc.) and the powder body material (glass microballoon, active carbon, bentonite etc.) and recycle, but all cause the reduction of photocatalytic activity and the problem that reclaims difficulty.

With TiO ₂Be coated on the soft magnetism nano-material surface and will make the advantage of its existing powdered form high catalytic activity, can utilize magnetic field to recycle again.Magnetic carries TiO at present ₂The preparation of photochemical catalyst mainly contains two kinds of forms: first kind is direct load TiO on the surface of magnetic nuclear ₂Second kind is to examine first load inert barriers load TiO again at magnetic ₂Process the photochemical catalyst of shell/shell/nuclear structure.Above-mentioned magnetic carries TiO ₂Photochemical catalyst adopts heat-treating methods at present mostly, yet there are many shortcomings in heat treatment: (1) causes the oxidation of magnetic nuclear, reduces the saturated magnetization rate, and recyclability is descended; (2) reduce specific area and surface hydroxyl and lose, thereby reduce catalytic activity; (3) second method adopts SiO mostly ₂And Al ₂O ₃As inert barriers, form magnetic screen Deng the inorganic matter material, reduced the magnetic recyclability.

Summary of the invention

Technical problem to be solved by this invention provides the magnetic carried catalyst TiO of a kind of effective raising catalytic activity and recyclability ₂/ PPY/Fe ₃O ₄The preparation method.

For addressing the above problem magnetic carried catalyst TiO of the present invention ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid is by 1～4: 0.5～2 volume ratio is mixed under 20～40 ℃ of conditions, and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then said mixed solution is moved in the thermostat water bath; Heated at constant temperature made it slaking in 1～3 hour under 50～70 ℃ of conditions, after the room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 0.5～1h; And, be 6.5～7.5 until the pH value with distilled water cyclic washing 3～5 times; Under 60～90 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate;

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of said step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 8～20 0.1mol/L FeCl ₃Solution, the rapid blackening of system continues reaction 8～15h, obtains PPY/Fe ₃O ₄Solution; Wherein said nanometer Fe ₃O ₄The mass volume ratio of particulate and said deionized water is 0.3～0.6: 100～300; Said neopelex (NaDBS) is 1～4: 100～300 with the mass volume ratio of said deionized water, and the volume ratio of said pyrrole monomer and said deionized water is 2～5: 100～300;

2. with said PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the said glass container outside, said PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down said magnet or said magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 50～90 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

1. after absolute ethyl alcohol and tetra-n-butyl titanate being mixed, obtain solution A; The mol ratio of wherein said tetra-n-butyl titanate and said absolute ethyl alcohol is 1: 30～50;

2. with the magnetic fluid PPY/Fe of said step (2) gained ₃O ₄Be seed, at said magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of said step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the said solution A; Containing said magnetic fluid PPY/Fe ₃O ₄Said solution A in add distilled water, and stir until said tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On: regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Said mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, after heating 10～20h under 120～190 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 60～95 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄Wherein said magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio of said solution A be 1: 200～350; The mol ratio of said tetra-n-butyl titanate and said distilled water is 1: 10～30; Said TiO ₂, PPY, Fe ₃O ₄Mol ratio be 20～40: 1.5～3: 1.

Said step (2) 2. in the magnetic retracting device comprise support and place the glass container on the said support; Be provided with the container that constitutes by the organic material protective layer in the said glass container, be filled with reactant liquor between this container and the said glass container; Bottom in the said container is provided with ferrite lattice, equidistantly is provided with a magnetic systems in it from top to bottom; Said ferrite lattice middle part links to each other with said support through conducting magnet core, and this conducting magnet core passes the center of said magnetic systems.

Said magnetic systems is made up of several neodymium iron boron bar magnets that are uniformly distributed with at grade; The end of said several neodymium iron boron bar magnets meets on the said conducting magnet core.

The present invention compared with prior art has the following advantages:

1, the present invention's magnetic of adopting polypyrrole (PPY) inert barriers and low temperature load method to prepare shell/shell/nuclear structure carries TiO ₂Photochemical catalyst; Since wherein polypyrrole (PPY) have insoluble molten, be prone to advantages such as polymerization, acidproof, alkaline-resisting, corrosion-resistant, good stability; The PPY protective layer can effectively stop the diffusion of magnetic nuclear matter and the photetching effect of magnetic carrier; Therefore, the photochemical catalyst that the present invention obtained has overcome the adverse effect that catalyst activity that conventional heat treatment causes and magnetic recyclability reduce.

The magnetic of shell/shell that 2, the present invention obtained/nuclear structure carries TiO ₂Photochemical catalyst is through X-ray diffractometer (XRD) test, and by the crystallite dimension of Scherrer equation calculation sample, its particle diameter is between 4～7nm; Calculate through formula W R=AR/ (0.884AA+AR); Wherein anatase accounts for 95.2%, and rutile accounts for 4.8%, is mixed crystal type (referring to Fig. 2).

The magnetic of shell/shell that 3, the present invention obtained/nuclear structure carries TiO ₂Photochemical catalyst is analyzed through photocatalytic degradation phenol (simulating pollution thing) test and vibrating specimen magnetometer (VSM); It has high catalytic activity again can recycle; The rate of recovery can reach more than 90%, compares in the environmental improvement field with other catalyst to have a good application prospect.

4, because the present invention adopts the low temperature load method; Many shortcomings that heat treatment exists have been overcome; Have high catalytic activity, can be recycled again, recycle 5 times after catalytic activity slightly reduce (referring to Fig. 1); This figure is that the phenol with 25mg/L is simulating pollution thing (phenol is stable), adopts 4-amino-antipyrine AAS to analyze; As can be seen from the figure, different catalysts photocatalytic degradation phenol Ln (C0/Ct) and reaction time t have good linear relationship, and catalyst TiO is described ₂, P25, TiO ₂/ PPY/Fe ₃O ₄The L-H kinetics equation is followed in degradation of phenol (simulating pollution thing) reaction, wherein direct sunshine photograph, TiO ₂, P25, MT K value (reaction rate) be respectively 0.001,0.0279,0.0264,0.0252, the TiO that above-mentioned data declaration is pure ₂Photocatalytic activity is a little more than P25 and MT, and MT is a little less than P25, and catalytic activity and the P25 of MT compare favourably, recycle 4 times after, the MT reaction rate is 0.020, only reduces by 0.0064, explains that prepared magnet carried photocatalyst has excellent catalytic activity; Its magnetic induction intensity is 40emu/g, has superparamagnetism (referring to Fig. 5), adopts retracting device that MT is reclaimed, and recycles average recovery rate and can reach 90.35%.Therefore, the magnetic of the present invention's preparation carries TiO ₂Photochemical catalyst has excellent catalytic activity and magnetic recyclability, has reduced the cost of investment of enterprise from the economic benefit aspect, from aspect, environmental protection field, economizes on resources, and recycle has a good application prospect.

5, sample of the present invention is carried out transmission electron microscope and electronic diffraction, obtain sample transmission electron microscope picture (TEM) and corresponding electronic diffraction ring (referring to Fig. 3).From figure, can know a: magnetic Fe ₃O ₄The outward appearance almost spherical; According to formula d=K/r, K is a constant, and r is an annular radii, and d is the indices of crystallographic plane, compares with JCPDF card (polycrystal powder diffraction card), can obtain the diffraction ring index of each electron diffraction diagram (SAED).The SAED diffraction ring index (220) of a, (311), (400), (440) are Fe ₃O ₄Several crystal faces of crystal; B: dark Fe ₃O ₄Wrap up the PPY of one deck light color around the core, and Fe ₃O ₄Nano particle is uniformly dispersed, and Fe among the present invention is described ₃O ₄Nano particle and polypyrrole are not simple blend, but are covered by polypyrrole inside; C:TiO ₂Even particle distribution; D:TiO ₂Be coated on Fe equably ₃O ₄On every side, and have PPY to exist between them; SAED figure among c, the d, its electronic diffraction chain index is that (101), (200), (202) explain that catalyst surface is anatase TiO ₂, the electronic diffraction chain index explains that for (301) catalyst surface also has rutile phase TiO ₂, the result is consistent with the XRD material phase analysis.

6, sample of the present invention is carried out examination of infrared spectrum, obtain the INFRARED SPECTRUM line chart (referring to Fig. 4) of sample.Can know that from Fig. 4 a is at 585.2cm ^-1The flexural vibrations absworption peak of Fe-O key has appearred in the place, is Fe ₃O ₄The principal character absworption peak; The b spectral line is at 680～880cm ^-1, 1265～1300cm ^-1, 1400～1500cm ^-1The characteristic absorpting spectruming line of PPY has appearred in the place, and their corresponding chemical bonds are respectively C-H, CH ₃And C=C, spectral line is at 585.2cm ^-1Fe does not appear ₃O ₄Characteristic absorption peak, Fe is described ₃O ₄Coated by PPY fully, the analysis result of this and XRD and TEM is consistent; C, d spectral line are at 1140cm ^-1Neighbouring is the flexural vibrations peak of Ti-O.Can know that from Fig. 4 the d spectral line is at 585.2cm ^-1Fe does not appear in the place ₃O ₄Characteristic absorption peak, reason are TiO ₂Be coated on Fe ₃O ₄Fe has been covered on the surface ₃O ₄Characteristic absorption peak, and c among Fig. 4 and d figure basically identical also can prove above-mentioned conclusion.B among Fig. 4 compares with the e figure, because Fe ₃O ₄Intervention, PPY/Fe ₃O ₄Absorption line some occur and move.

Description of drawings

Do further detailed explanation below in conjunction with the accompanying drawing specific embodiments of the invention.

Fig. 1 is TiO of the present invention ₂, P25, MT (be TiO ₂/ PPY/Fe ₃O ₄) reaction degradation rate figure; Wherein a represents TiO ₂, b represents P25, and c represents MT, and d represents MT circulation 4 times, and e represents blank.

Fig. 2 is Fe of the present invention ₃O ₄, PPY/Fe ₃O ₄, TiO ₂XRD spectra with MT; Wherein a or F represent Fe ₃O ₄, b represents PPY/Fe ₃O ₄, c represents TiO ₂, d represents MT, and A represents the anatase phase, and R represents the rutile phase.

Fig. 3 is Fe of the present invention ₃O ₄, PPY/Fe ₃O ₄, TiO ₂Transmission electron microscope picture (TEM) and corresponding electronic diffraction ring with MT; Wherein a represents Fe ₃O ₄, b represents PPY/Fe ₃O ₄, c represents TiO ₂, d represents MT.

Fig. 4 is Fe of the present invention ₃O ₄, PPY/Fe ₃O ₄, TiO ₂, and the infrared spectrum of MT, PPY sample; Wherein a represents Fe ₃O ₄, b represents PPY/Fe ₃O ₄, c represents TiO ₂, d represents MT, and e represents PPY.

Fig. 5 is Fe of the present invention ₃O ₄, PPY/Fe ₃O ₄, and the hysteresis curve of MT; Wherein a represents Fe ₃O ₄, b represents PPY/Fe ₃O ₄, c represents MT.

Fig. 6 is the structural representation of magnetic retracting device among the present invention.

Among the figure: 1-support 2-glass container 3-organic material protective layer 4-reactant liquor 5-ferrite lattice 6-magnetic systems 7-neodymium iron boron bar magnet.

The specific embodiment

Embodiment 1 magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid mixes under 20 ℃ of conditions by 1: 1 volume ratio (mL/mL), and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then mixed solution is moved in the thermostat water bath, heated at constant temperature made it slaking in 3 hours under 50 ℃ of conditions, after room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 0.5h, and with distilled water cyclic washing 3～5 times, be 6.5～7.5 until the pH value; Under 60 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate.

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 8 0.1mol/LFeCl ₃Solution, the rapid blackening of system continues reaction 8h, obtains PPY/Fe ₃O ₄Solution.

Wherein: nanometer Fe ₃O ₄The mass volume ratio of particulate and deionized water (g/mL) is 0.3: 100, and neopelex (NaDBS) is 1: 100 with the mass volume ratio (g/mL) of deionized water, and the volume ratio of pyrrole monomer and deionized water (mL/mL) is 2: 100.

2. with PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the glass container outside, PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down magnet or magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 50 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

1. after absolute ethyl alcohol and tetra-n-butyl titanate being mixed, obtain solution A; Wherein the mol ratio of tetra-n-butyl titanate and absolute ethyl alcohol is 1: 30.

2. with the magnetic fluid PPY/Fe of step (2) gained ₃O ₄Be seed, at magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the solution A; Containing magnetic fluid PPY/Fe ₃O ₄Solution A in add distilled water, and stir until the tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On; Regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, behind heating 20h under 120 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 60 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄

Wherein: magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio (g/mL) of solution A be 1: 200; The mol ratio of tetra-n-butyl titanate and distilled water is 1: 10; TiO ₂, PPY, Fe ₃O ₄Mol ratio be 20: 1.5: 1.

Embodiment 2 magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid mixes under 40 ℃ of conditions by 4: 2 volume ratio (mL/mL), and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then mixed solution is moved in the thermostat water bath, heated at constant temperature made it slaking in 1 hour under 70 ℃ of conditions, after room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 1h, and with distilled water cyclic washing 3～5 times, be 6.5～7.5 until the pH value; Under 90 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate.

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 20 0.1mol/LFeCl ₃Solution, the rapid blackening of system continues reaction 15h, obtains PPY/Fe ₃O ₄Solution.

Wherein: nanometer Fe ₃O ₄The mass volume ratio of particulate and deionized water (g/mL) is 0.3: 200, and neopelex (NaDBS) is 2: 150 with the mass volume ratio (g/mL) of deionized water, and the volume ratio of pyrrole monomer and deionized water (mL/mL) is 3: 200.

2. with PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the glass container outside, PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down magnet or magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 90 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

1. after absolute ethyl alcohol and tetra-n-butyl titanate being mixed, obtain solution A; Wherein the mol ratio of tetra-n-butyl titanate and absolute ethyl alcohol is 1: 40.

2. with the magnetic fluid PPY/Fe of step (2) gained ₃O ₄Be seed, at magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the solution A; Containing magnetic fluid PPY/Fe ₃O ₄Solution A in add distilled water, and stir until the tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On; Regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, behind heating 10h under 190 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 95 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄

Wherein: magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio (g/mL) of solution A be 1: 250; The mol ratio of tetra-n-butyl titanate and distilled water is 1: 30; TiO ₂, PPY, Fe ₃O ₄Mol ratio be 30: 2.1: 1.

Embodiment 3 magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid mixes under 30 ℃ of conditions by 2: 1 volume ratio (mL/mL), and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then mixed solution is moved in the thermostat water bath, heated at constant temperature made it slaking in 2 hours under 60 ℃ of conditions, after room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 0.8h, and with distilled water cyclic washing 3～5 times, be 6.5～7.5 until the pH value; Under 70 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate.

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 14 0.1mol/LFeCl ₃Solution, the rapid blackening of system continues reaction 11h, obtains PPY/Fe ₃O ₄Solution.

Wherein: nanometer Fe ₃O ₄The mass volume ratio of particulate and deionized water (g/mL) is 0.5: 200, and neopelex (NaDBS) is 3: 200 with the mass volume ratio (g/mL) of deionized water, and the volume ratio of pyrrole monomer and deionized water (mL/mL) is 4: 300.

2. with PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the glass container outside, PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down magnet or magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 70 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

2. with the magnetic fluid PPY/Fe of step (2) gained ₃O ₄Be seed, at magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the said solution A; Containing magnetic fluid PPY/Fe ₃O ₄Solution A in add distilled water, and stir until the tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On; Regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, behind heating 15h under 150 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 75 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄

Wherein: magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio (g/mL) of solution A be 1: 300; The mol ratio of tetra-n-butyl titanate and distilled water is 1: 20; TiO ₂, PPY, Fe ₃O ₄Mol ratio be 30: 2.5: 1.

Embodiment 4 magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid mixes under 25 ℃ of conditions by 2: 1 volume ratio (mL/mL), and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then mixed solution is moved in the thermostat water bath, heated at constant temperature made it slaking in 1.5 hours under 55 ℃ of conditions, after room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 0.6h, and with distilled water cyclic washing 3～5 times, be 6.5～7.5 until the pH value; Under 80 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate.

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 10 0.1mol/LFeCl ₃Solution, the rapid blackening of system continues reaction 10h, obtains PPY/Fe ₃O ₄Solution.

Wherein: nanometer Fe ₃O ₄The mass volume ratio of particulate and deionized water (g/mL) is 0.3: 100, and neopelex (NaDBS) is 4: 300 with the mass volume ratio (g/mL) of deionized water, and the volume ratio of pyrrole monomer and deionized water (mL/mL) is 5: 300.

2. with PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the glass container outside, PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down magnet or magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 60 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

1. after absolute ethyl alcohol and tetra-n-butyl titanate being mixed, obtain solution A; Wherein the mol ratio of tetra-n-butyl titanate and absolute ethyl alcohol is 1: 50.

2. with the magnetic fluid PPY/Fe of step (2) gained ₃O ₄Be seed, at magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the said solution A; Containing magnetic fluid PPY/Fe ₃O ₄Solution A in add distilled water, and stir until the tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On; Regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, behind heating 18h under 140 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 85 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄

Wherein: magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio (g/mL) of solution A be 1: 350; The mol ratio of tetra-n-butyl titanate and distilled water is 1: 25; TiO ₂, PPY, Fe ₃O ₄Mol ratio be 40: 3: 1.

Embodiment 5 magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄The preparation method, may further comprise the steps:

(1) nanometer Fe ₃O ₄The preparation of particle:

Concentration is respectively the Fe of 0.1mol/L ^{+ 3}And Fe ^{+ 2}Salting liquid mixes under 35 ℃ of conditions by 3: 0.5 volume ratio (mL/mL), and to add concentration be the NaOH solution of 1mol/L, is 9～11 until the pH value, obtains mixed solution; Then mixed solution is moved in the thermostat water bath, heated at constant temperature made it slaking in 2.5 hours under 65 ℃ of conditions, after room temperature cooling, added absolute ethyl alcohol and adopted magnetic agitation 0.6h, and with distilled water cyclic washing 3～5 times, be 6.5～7.5 until the pH value; Under 75 ℃ of conditions, dry at last, after cooling, grinding, crossing 300 mesh sieves, promptly get nanometer Fe to constant weight ₃O ₄Particulate.

(2) magnetic fluid PPY/Fe ₃O ₄Preparation:

1. under the room temperature with the nanometer Fe of step (1) gained ₃O ₄Particulate, neopelex (NaDBS) and after deionized water mixed, magnetic agitation was even, the pyrrole monomer that reinjects then splashes into 15 0.1mol/LFeCl ₃Solution, the rapid blackening of system continues reaction 12h, obtains PPY/Fe ₃O ₄Solution.

Wherein: nanometer Fe ₃O ₄The mass volume ratio of particulate and deionized water (g/mL) is 0.6: 300, and neopelex (NaDBS) is 4: 250 with the mass volume ratio (g/mL) of deionized water, and the volume ratio of pyrrole monomer and deionized water (mL/mL) is 4: 250.

2. with PPY/Fe ₃O ₄Solution moves into glass container, puts magnet or magnetic retracting device in the glass container outside, PPY/Fe under the effect of magnetic field ₃O ₄PPY/Fe in the solution ₃O ₄Supernatant is outwelled in the rapid sedimentation of particle, takes down magnet or magnetic retracting device, collects the PPY/Fe in the solution ₃O ₄, this PPY/Fe ₃O ₄Behind difference water and the absolute ethanol washing 3～5 times, under 80 ℃ of conditions, be dried to constant weight, promptly get magnetic fluid PPY/Fe ₃O ₄

(3) TiO ₂/ PPY/Fe ₃O ₄Preparation of catalysts:

1. after absolute ethyl alcohol and tetra-n-butyl titanate being mixed, obtain solution A; Wherein the mol ratio of tetra-n-butyl titanate and absolute ethyl alcohol is 1: 45.

2. with the magnetic fluid PPY/Fe of step (2) gained ₃O ₄Be seed, at magnetic fluid PPY/Fe ₃O ₄In add the 1. solution A of gained of step, through magnetic agitation 30 minutes, make PPY/Fe ₃O ₄Be evenly dispersed in the said solution A; Containing magnetic fluid PPY/Fe ₃O ₄Solution A in add distilled water, and stir until the tetra-n-butyl titanate complete hydrolysis, this moment TiO ₂Be coated on PPY/Fe ₃O ₄On; Regulate its pH value to 6.5～7.5 with glacial acetic acid again, obtain mixed liquor; Mixed liquor is put into hydrothermal reaction kettle, put into Muffle furnace to hydrothermal reaction kettle again, behind heating 18h under 160 ℃ of conditions; Take out hydrothermal reaction kettle; Use absolute ethyl alcohol and distilled water cyclic washing several after the normal temperature cooling successively, up to there not being peculiar smell, and under 65 ℃ of conditions, dry to constant weight; Through grinding, crossing 150 mesh sieves, promptly get magnetic carried catalyst TiO ₂/ PPY/Fe ₃O ₄

Wherein: magnetic fluid PPY/Fe ₃O ₄With the mass volume ratio (g/mL) of solution A be 1: 350; The mol ratio of tetra-n-butyl titanate and distilled water is 1: 15; TiO ₂, PPY, Fe ₃O ₄Mol ratio be 35: 3: 1.

Step in the foregoing description 1～5 (2) 2. in the magnetic retracting device be to comprise support 1 and place the glass container 2 on the support 1.Be provided with the container that constitutes by organic material protective layer 3 in the glass container 2, be filled with reactant liquor 4 between this container and the glass container 2; Bottom in the container is provided with ferrite lattice 5, equidistantly is provided with a magnetic systems 6 in it from top to bottom; Ferrite lattice 5 middle parts link to each other with support 1 through conducting magnet core, and this conducting magnet core passes the center (referring to Fig. 6) of magnetic systems 6.

Magnetic systems 6 is made up of several neodymium iron boron bar magnets 7 that are uniformly distributed with at grade; The end of several neodymium iron boron bar magnets 7 meets on the conducting magnet core.

Claims

1. The preparation method of magnetically supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ comprises the following steps:

(1) Preparation of nanometer Fe ₃ O ₄ particles:

Mix the Fe ⁺³ and Fe ⁺² salt solutions with a concentration of 0.1mol/L respectively at a volume ratio of 1~4:0.5~2 at 20~40°C, and add a NaOH solution with a concentration of 1mol/L, Until the pH value is 9-11, a mixed solution is obtained; then the mixed solution is moved to a constant temperature water bath, heated at a constant temperature of 50-70°C for 1-3 hours to mature, and after cooling at room temperature, add anhydrous The ethanol was magnetically stirred for 0.5-1h, and washed repeatedly with distilled water for 3-5 times until the pH value was 6.5-7.5; finally, it was dried at 60-90°C to constant weight, cooled, ground, and passed through a 300-mesh sieve. That is, nano Fe ₃ O ₄ particles are obtained;

(2) Preparation of magnetic fluid PPY/Fe ₃ O ₄ :

① Mix the nano- _Fe3O4 particles obtained in _the step (1), sodium dodecylbenzenesulfonate and deionized water at room temperature, stir evenly with a magnetic force, inject pyrrole monomer, and then drop 8 to 20 Drop 0.1mol/L FeCl ₃ solution, the system turns black rapidly, continue to react for 8-15 hours, and obtain PPY/Fe ₃ O ₄ solution; wherein the mass volume ratio of the nano-Fe ₃ O ₄ particles to the deionized water is 0.3- 0.6: 100～300, the mass volume ratio of described sodium dodecylbenzene sulfonate and described deionized water is 1～4: 100～300, the volume ratio of described pyrrole monomer and described deionized water is 2～5:100～300;

②Put the PPY/Fe ₃ O ₄ solution into a glass container, place a magnet or a magnetic recovery device on the outside of the glass container, and under the action of a magnetic field, the PPY/Fe ₃ OX particles in the PPY/Fe ₃ O ₄ solution Settle rapidly, discard the supernatant, remove the magnet or the magnetic recovery device, collect the PPY/Fe ₃ O ₄ in the solution, and wash the PPY/Fe ₃ O ₄ with water and absolute ethanol for 3 to 5 times respectively Finally, dry to constant weight at 50-90°C to obtain the magnetic fluid PPY/Fe ₃ O ₄ ;

(3) Preparation of TiO ₂ /PPY/Fe ₃ O ₄ catalyst:

① After uniformly mixing absolute ethanol and tetra-n-butyl titanate, a solution A is obtained; wherein the molar ratio of the tetra-n-butyl titanate to the absolute ethanol is 1:30-50;

② Using the magnetic fluid PPY/Fe ₃ O ₄ obtained in the step (2) as a seed, add the solution A obtained in the step ① to the magnetic fluid PPY/Fe ₃ O ₄ , and stir it magnetically for 30 minutes to make PPY/Fe ₃ O ₄ is uniformly dispersed in the solution A; distilled water is added to the solution A containing the magnetic fluid PPY/Fe ₃ O ₄ and stirred until the tetra-n-butyl titanate is completely hydrolyzed , at this time, TiO ₂ is coated on PPY/Fe ₃ O ₄ ; then the pH value is adjusted to 6.5-7.5 with glacial acetic acid to obtain a mixed solution; the mixed solution is put into a hydrothermal reaction kettle, and then the hydrothermal Put the reaction kettle into a muffle furnace, heat it at 120-190°C for 10-20 hours, take out the hydrothermal reaction kettle, cool it at room temperature, wash it repeatedly with absolute ethanol and distilled water several times until there is no peculiar smell, and put it in 60 Drying at ~95°C to constant weight, grinding and passing through a 150-mesh sieve to obtain the magnetically supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ ; wherein the magnetic fluid PPY/Fe ₃ O ₄ and the solution A The mass-volume ratio of the titanate is 1:200-350; the molar ratio of the tetra-n-butyl titanate to the distilled water is 1:10-30; the molar ratio of the _TiO2 , _PPY , _Fe3O4 is 20- 40:1.5～3:1.

2. the preparation method of magnetically supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ as claimed in claim 1, it is characterized in that: the magnetic recovery device in 2. of described step (2) comprises support (1) and is placed The glass container (2) on the support (1); the glass container (2) is provided with a container made of an organic material protective layer (3), and the container and the glass container (2) are filled with reaction solution (4); the bottom of the container is provided with a ferrite magnet (5), and a magnetic system (6) is arranged at equal intervals from top to bottom; the middle part of the ferrite magnet (5) passes through the guide The magnetic core is connected with the support (1), and the permeable magnetic core passes through the center of the magnetic system (6).

3. The preparation method of the magnetically supported catalyst TiO ₂ /PPY/Fe ₃ O ₄ as claimed in claim 2, characterized in that: the magnetic system (6) consists of several neodymium iron boron magnets evenly distributed on the same plane rods (7); the ends of the several NdFeB magnetic rods (7) converge on the permeable core.