CN101748428A - Preparation method for preparing expanded graphite modified composite electrode of hydrogen peroxide - Google Patents

Preparation method for preparing expanded graphite modified composite electrode of hydrogen peroxide Download PDF

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CN101748428A
CN101748428A CN200810209549A CN200810209549A CN101748428A CN 101748428 A CN101748428 A CN 101748428A CN 200810209549 A CN200810209549 A CN 200810209549A CN 200810209549 A CN200810209549 A CN 200810209549A CN 101748428 A CN101748428 A CN 101748428A
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expanded graphite
composite electrode
hydrogen peroxide
preparation
modified composite
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CN101748428B (en
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于秀娟
赵琪
邢子鹏
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Heilongjiang University
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Abstract

The invention provides a preparation method for preparing an expanded graphite modified composite electrode of hydrogen peroxide. The prior arts in the field all have disadvantages. The method comprises the following steps of preparing expanded graphite, mixing and stirring 0-25 parts of prepared expanded graphite with 75-100 parts of active carbon, dripping and impregnating 1-2 parts of absolute ethyl alcohol into the solid mixed powder, putting the mixture into an ultrasonator so as to carry out ultrasonic processing, dripping 25-50 parts of PTFE emulsion after drying for 24h, stirring in a water bath with the temperature of 60-70 DEG C while adding, adding 1-2 parts of absolute ethyl alcohol again, mixing so as to form a paste body, and preparing the expanded graphite modified composite electrode with a smooth surface by putting the mixed paste body on a tablet press for rolling when the paste body is hot. The prepared expanded graphite modified composite electrode is used for preparing the hydrogen peroxide.

Description

Be used to produce the preparation method of the expanded graphite modified composite electrode of hydrogen peroxide
Technical field:
The present invention relates to the preparation method of Preparation of Expanded Graphite, expanded graphite-carbon dust-tetrafluoroethylene composite electrode, this electrode is used for cathodic oxygen reduction and produces hydrogen peroxide.
Background technology:
The oxygen cathode reduction method prepares hydrogen peroxide, and energy consumption is low in theory, and is simple to operate, and the technology of particularly making the gas diffusion cathode that is applicable to hydrogen peroxide manufacture has obtained suitable improvement.This method and vitriol electrolytic process relatively, energy consumption can reduce significantly, its in theory power consumption only account for 23.7% of vitriol electrolytic process power consumption; With anthraquinone comparison, do not need hydrogen, oxygen, hidden danger such as blast not, throughput is not limited by scale.Its advantage is: utilize inexhaustible empty G﹠W to obtain alkaline hydrogen peroxide for one step of raw material, simplified Production Flow Chart, for the enterprise that needs alkaline hydrogen peroxide water solution in a large number provides rig-site utilization equipment, factory replaces and buys the commodity hydrogen peroxide by setting up alkaline hydrogen peroxide water solution generator.Can save the taking of concentrated expense, packing charge, transport charge, standing loss, current assets of hydrogen peroxide, and the profit of hydrogen peroxide manufacture factory and tax revenue, can also eliminate the danger that the diluting high-concentration hydrogen peroxide brings, therefore can significantly reduce the actual cost of hydrogen peroxide.
Since the sixties, a lot of impressive progresses have been obtained in the research aspect the electroreduction oxygen production alkaline hydrogen peroxide, some patents have appearred, but up to now also less than the precedent that formally comes into operation with technical scale, tracing it to its cause is exactly that these methods have run into all difficulties in dropping into industrial production, for example:
With the graphite granule is the method for cathode material, and for example US3969201 will make this method reach industrial available working index, must use pure oxygen and require and work under elevated pressures, and it is difficult that such working conditions causes electrode to maximize;
With the carbon felt is cathode material, " Development of Trickled-BedElectrolyzer for On-Site Electrochemical Production of Hydrogen Peroxide " Journal of the Electrochemical Society as Yamada etc., 1999,146 (7): 2487~2591, for making this method drop into industrial production, at the electrode outside need with the saturated repeatedly a large amount of round-robin cathode solution of oxygen, so complicated operation, running cost costliness;
With carbon black, gac or graphite is raw material, adds the hydrophobic substance of tetrafluoroethylene and so on, makes membranaceous oxygen electrode on the net at metallic nickel, as US4384931, US4357217.Also obtained working index preferably with this method, but still exist electrode and soaked into by buck and the shortcoming that lost efficacy, and every plate electrode all need be provided with wind box, make its structure complicated, especially when dropping into industrial application, to make hundreds of large size diaphragm, these diaphragm-operated Gas permeability uniformities are difficult for, so when maximizing, also meet difficulty.
Make cathode material such as US4067787 with graphite or glass charcoal, this patent is to reach industrial feasible working index, the catalyzer that in cathode solution, adds suitable concentration, as 2, the 7-anthraquinone disulphonate, the alternation that utilizes the oxidation state of catalyzer and go back ortho states is finished the preparation of alkaline hydrogen peroxide, and its working index is more satisfactory, but shortcoming is that (alkaline hydrogen peroxide) is mixed with a large amount of catalyzer in cathode product, needs a series of separation formalities to separate catalyzer and hydrogen peroxide.
Use contains the quinone air cathode, rely on the quinones substance that contains in the negative electrode carbon core to carry out the redox alternation response, the reaction process of anthraquinone preparing hydrogen peroxide transferred on the electrode carry out, as CN87103988, do not separate though this method does not need to carry out product afterwards, need to adopt low-pressure air under the condition of sealing, to move.
Summary of the invention:
The purpose of this invention is to provide a kind of preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, this electrode is used for cathodic oxygen reduction and produces hydrogen peroxide.
Above-mentioned purpose realizes by following technical scheme:
Be used to produce the preparation method of the expanded graphite modified composite electrode of hydrogen peroxide, its composition comprises: the preparation expanded graphite, the expanded graphite that makes is got 0-25 part by weight to be mixed, stirs with 75-100 part gac and drip 1-2 part dehydrated alcohol to above-mentioned solid mixed powder and soak into, place ultrasonator to carry out supersound process, be added dropwise to 25-50 part ptfe emulsion after dry 24 hours, the limit edged stirs in 60-70 ℃ water-bath, adds 1-2 part dehydrated alcohol again and is lotion; The lotion that to become reconciled is placed on while hot and carries out the expanded graphite modified composite electrode that roll-in makes surfacing on the tabletting machine.
The described preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, described preparation expanded graphite is that to get concentration by weight be that vitriol oil 15-20 part of 98% is poured in the beaker, under constantly stirring, 5-10 part crystalline flake graphite and 1-2 part potassium permanganate mixed and pour in the vitriol oil, heating in water bath in 40-60 ℃ temperature range, carried out intercalation 1 hour, get mixture with 200 purpose Stainless Steel Wire net filtrations, described mixture is washed to neutrality, the baking oven of putting into 70 ℃ is dry, put into microwave oven more expanded 10 seconds, and made expanded graphite.
The described preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, described roll-in is that the lotion of will become reconciled is placed on the tabletting machine while hot, adjust spacing 3-5mm, progressively dwindle spacing to 2mm repetitive operation then and be pressed into two, to be clipped in the middle of two sheets that are pressed into through pretreated stainless (steel) wire, adjust spacing 5mm, continue rollingly, promptly get the expanded graphite modified composite electrode of surfacing.
The described preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, the pre-treatment of described stainless (steel) wire comprises alkali cleaning and pickling, described alkali cleaning is to get 20 parts in sodium hydroxide, 20 parts of mixed dissolutions of sodium phosphate by weight, with volume parts is 1 part distilled water constant volume, boils described stainless (steel) wire and take out flushing after 0.5 hour under 80-90 ℃ of temperature condition; Described pickling is to use the stainless (steel) wire of the hydrochloric acid soln of 0.1mol/L immersion after alkali cleaning 0.5 hour, and flushing is dried; Described weight is g:L with the corresponding unit of volume.
Beneficial effect of the present invention:
1. form vermicular texture behind the expansible black lead process microwave bulking that the present invention adopts, the back graphite apparent volume that expands reaches 250~300ml/g or bigger;
2. gac, expanded graphite, three kinds of materials of polytetrafluoroethylene PTFE disperse comparatively even in the modified composite electrode of the present invention's preparation;
3. the modified composite electrode of the present invention's preparation is because the adding resistivity of expanded graphite reduces, and electroconductibility strengthens;
4. the oxygen generation electrochemical reduction of the modified composite electrode of the present invention preparation in can catalytic air generates hydrogen peroxide.
Description of drawings:
Accompanying drawing 1 is the stereoscan photograph figure of the expanded graphite for preparing of the present invention.
Accompanying drawing 2 is expanded graphites of preparing of the present invention through the stereoscan photograph figure of the expanded graphite of the vermicular texture that forms behind the microwave bulking.
Accompanying drawing 3 is expanded graphite modified gac/polytetrafluoroethylene PTFE composite electrode electromicroscopic photograph figure.
Accompanying drawing 4 is polarization curves of the composite electrode of different content expanded graphite.On behalf of expanded graphite content, five curves be respectively 5%, 10%, 15%, 20% and 25% from the bottom to top among the figure.
Embodiment:
Embodiment 1:
Be used to produce the preparation method of the expanded graphite modified composite electrode of hydrogen peroxide, its composition comprises: the preparation expanded graphite, the expanded graphite that makes is got 0.75 gram to be mixed, stirs with 2.25 gram gacs and drip the extremely above-mentioned solid mixed powder infiltration of 0.03 gram dehydrated alcohol, place ultrasonator to carry out supersound process, be added dropwise to 0.75 gram ptfe emulsion after dry 24 hours, the limit edged stirs in 60-70 ℃ water-bath, adds 0.03 gram dehydrated alcohol again and is lotion; The lotion that to become reconciled is placed on while hot and carries out the expanded graphite modified composite electrode that roll-in makes surfacing on the tabletting machine.
Embodiment 2:
The above-mentioned preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, described preparation expanded graphite is to be that 98% vitriol oil 15-20 gram is poured in the beaker with concentration, under constantly stirring, 10 gram crystalline flake graphites and 2 gram potassium permanganate are mixed and pour in the vitriol oil, heating in water bath in 40-60 ℃ temperature range, carried out intercalation 1 hour, get mixture with 200 purpose Stainless Steel Wire net filtrations, described mixture is washed to neutrality, the baking oven of putting into 70 ℃ is dry, put into microwave oven more expanded 10 seconds, and made expanded graphite.
Embodiment 3:
The above-mentioned preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, described roll-in is that the lotion of will become reconciled is placed on the tabletting machine while hot, adjust spacing 3-5mm, progressively dwindle spacing to 2mm repetitive operation then and be pressed into two, to be clipped in the middle of two sheets that are pressed into through pretreated stainless (steel) wire, adjust spacing 5mm, continue rollingly, promptly get the expanded graphite modified composite electrode of surfacing.
Embodiment 4:
The above-mentioned preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, the pre-treatment of described stainless (steel) wire comprises alkali cleaning and pickling, described alkali cleaning is to get sodium hydroxide 20 grams, sodium phosphate 20 gram mixed dissolutions, with 1 liter distilled water constant volume, under 80-90 ℃ of temperature condition, boil described stainless (steel) wire and take out flushing after 0.5 hour; Described pickling is to use the stainless (steel) wire of the hydrochloric acid soln of 0.1mol/L immersion after alkali cleaning 0.5 hour, and flushing is dried; Described weight is g:L with the corresponding unit of volume.
Adopt the Dutch FEI Sirion of PHILIPS Co. type scanning electronic microscope (SEM) to observe without the expansible black lead of high temperature puffing and the apparent pattern of expanded graphite.Shown in accompanying drawing 1, accompanying drawing 2, as seen the graphite apparent volume reaches 250~300ml/g or bigger behind microwave expansion.By accompanying drawing 3 as seen, gac, expanded graphite, three kinds of materials of PTFE disperse comparatively even in prepared expanded graphite modified gac/PTFE combined electrode.
The resistance measurement of composite electrode:
Change the ratio of expanded graphite and gac, preparation expanded graphite quality accounts for mixture quality than the combined electrode that is 0~25%, and it is as shown in table 1 to measure its resistance, as seen increases with expanded graphite content, and the resistance of the electrode of preparation reduces.
Table 1
Figure G2008102095496D0000051
The mensuration of polarization curve:
The polarization curve of different expanded graphite content composite electrodes as shown in Figure 4.Increase with expanded graphite content, depressing it in same electrical also increases to some extent by electric current, so polarization curve rises with the increase of expanded graphite content.
Hydrogen reduction generates the detection of hydrogen peroxide:
As negative electrode, in two electrode electrolysers, adopt potentiostatic electrolysis research cathodic oxygen reduction with the expanded graphite modified gac/PTFE composite electrode of the present invention preparation.Adopt volumetry to detect the amount of oxygen at the hydrogen peroxide of cathodic reduction generation.Bubbling air in the electrolysis forward direction solution, with airborne oxygen as reaction raw materials.Table 2 is the amount of the gac/PTFE composite electrode of different expanded graphite content detected hydrogen peroxide during as negative electrode.As can be seen from Table 2, the adding of expanded graphite helps improving the generation of hydrogen peroxide.
Table 2
Figure G2008102095496D0000052

Claims (4)

1. preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide, its composition comprises: the preparation expanded graphite, it is characterized in that: the expanded graphite that makes is got 0-25 part by weight mix, stir with 75-100 part gac and drip 1-2 part dehydrated alcohol to above-mentioned solid mixed powder and soak into, place ultrasonator to carry out supersound process, be added dropwise to 25-50 part ptfe emulsion after dry 24 hours, the limit edged stirs in 60-70 ℃ water-bath, adds 1-2 part dehydrated alcohol again and is lotion; The lotion that to become reconciled is placed on while hot and carries out the expanded graphite modified composite electrode that roll-in makes surfacing on the tabletting machine.
2. the preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide according to claim 1, it is characterized in that: described preparation expanded graphite is that to get concentration by weight be that vitriol oil 15-20 part of 98% is poured in the beaker, under constantly stirring, 5-10 part crystalline flake graphite and 1-2 part potassium permanganate mixed and pour in the vitriol oil, heating in water bath in 40-60 ℃ temperature range, carried out intercalation 1 hour, get mixture with 200 purpose Stainless Steel Wire net filtrations, described mixture is washed to neutrality, the baking oven of putting into 70 ℃ is dry, put into microwave oven more expanded 10 seconds, and made expanded graphite.
3. the preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide according to claim 1 and 2, it is characterized in that: described roll-in is that the lotion of will become reconciled is placed on the tabletting machine while hot, adjust spacing 3-5mm, progressively dwindle spacing to 2mm repetitive operation then and be pressed into two, to be clipped in the middle of two sheets that are pressed into through pretreated stainless (steel) wire, adjust spacing 5mm, continue rollingly, promptly get the expanded graphite modified composite electrode of surfacing.
4. the preparation method who is used to produce the expanded graphite modified composite electrode of hydrogen peroxide according to claim 3, it is characterized in that: the pre-treatment of described stainless (steel) wire comprises alkali cleaning and pickling, described alkali cleaning is to get 20 parts in sodium hydroxide, 20 parts of mixed dissolutions of sodium phosphate by weight, with volume parts is 1 part distilled water constant volume, boils described stainless (steel) wire and take out flushing after 0.5 hour under 80-90 ℃ of temperature condition; Described pickling is to use the stainless (steel) wire of the hydrochloric acid soln of 0.1mol/L immersion after alkali cleaning 0.5 hour, and flushing is dried; Described weight is g: L with the corresponding unit of volume.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103046072A (en) * 2012-12-31 2013-04-17 黑龙江大学 Mn/Nano-G|foam-Ni/Pd combination electrode and preparation method thereof
CN103131104A (en) * 2012-11-13 2013-06-05 高润宝 Preparing method of polytetrafluoroethylene / polyaniline electroconductive plastic modified by expanded graphite
CN103131105A (en) * 2012-11-13 2013-06-05 高润宝 Polytetrafluoroethylene / polyaniline electro-conductive plastic modified by expanded graphite
CN108085714A (en) * 2018-01-12 2018-05-29 齐鲁工业大学 A kind of preparation method and applications of novel gas diffusion electrodes
CN109252182A (en) * 2017-07-12 2019-01-22 天津大学 A method of preparing diamond-like presoma
CN110565112A (en) * 2019-08-19 2019-12-13 天津大学 method for changing cathode oxygen reduction activity by regulating hydrophilicity and hydrophobicity

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Publication number Priority date Publication date Assignee Title
CN100341179C (en) * 2004-08-17 2007-10-03 中国电子科技集团公司第十八研究所 Positive electrode for zinc-air battery and its manufacturing method

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103131104A (en) * 2012-11-13 2013-06-05 高润宝 Preparing method of polytetrafluoroethylene / polyaniline electroconductive plastic modified by expanded graphite
CN103131105A (en) * 2012-11-13 2013-06-05 高润宝 Polytetrafluoroethylene / polyaniline electro-conductive plastic modified by expanded graphite
CN103131104B (en) * 2012-11-13 2015-09-09 高润宝 The preparation method of expanded graphite modified tetrafluoroethylene/layer/polyaniline conductive plastics
CN103131105B (en) * 2012-11-13 2016-06-22 银川博聚工业产品设计有限公司 Expanded graphite modified politef/layer/polyaniline conductive plastics
CN103046072A (en) * 2012-12-31 2013-04-17 黑龙江大学 Mn/Nano-G|foam-Ni/Pd combination electrode and preparation method thereof
CN103046072B (en) * 2012-12-31 2015-03-11 黑龙江大学 Mn/Nano-G|foam-Ni/Pd combination electrode and preparation method thereof
CN109252182A (en) * 2017-07-12 2019-01-22 天津大学 A method of preparing diamond-like presoma
CN108085714A (en) * 2018-01-12 2018-05-29 齐鲁工业大学 A kind of preparation method and applications of novel gas diffusion electrodes
CN110565112A (en) * 2019-08-19 2019-12-13 天津大学 method for changing cathode oxygen reduction activity by regulating hydrophilicity and hydrophobicity

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