CN1117021A - Anode oxidative treatment method and apparatus for producing expansible graphite - Google Patents

Abstract

The present invention belongs to material science and its implement can raise the stratification homogenity and production of expansible graphite produced by electrochemical process, realize continuous charging and discharging of material in anode oxidation treatment, and realize prodn automation. Its main feature is that in the flowing pipe-type anode oxidative treating system, the graphite material mixed with electrolyte liquid is anode oxidative treated in the flow course; and it is first passed anode area, then through the cathode area, and finally enters collector after reaching certain stratification degree.

Description

A kind of anode oxidative treatment method and device of producing expansible black lead

Title of the present invention is called a kind of anode oxidative treatment method and device of producing expansible black lead, and it belongs to material science.

Existing technology status: the conventional production methods of expansible black lead is a chemical method, and it need be with a large amount of concentrated acids and considerable oxygenant, so environmental issue is big, and workman's labor condition is poor, the cost height, and quality is low.In recent ten years, countries in the world all propose variously to produce expansible black lead with anode oxidative treatment method and (see that the Japanese Patent spy opens clear 55-62807 in succession; 56-90989; China patent CN1061387A etc.) they need acid few, and environmental issue is little, and workman's labor condition makes moderate progress, and product comprehensive quality is good.But so far, the productivity of existing anodic oxidation treatment technology is all lower, its typical yield～～0.5 gram/square centimeter hour, the interlayer degree lack of homogeneity of graphite granule in the product, this ununiformity, even in the anode oxidative treatment method of proximal pole anomaly column electrode template or the product at the anode oxidative treatment method of pressurization, still obviously exist, what just general distal pole anomaly column electrode plate was produced on uneven degree is little.In addition, these methods all are that a groove one trough carries out, be disposable feeding intake, through the reasonable time anodic oxidation treatment after disposable discharging, perhaps in preceding method, add whipping appts or adopt the rotating anode method, though make the product homogeneity obtain some improvement, but equipment is complicated, investment is big, yield is not high yet, and also is accompanied by the shortcomings such as the further refinement of quilt of crystalline flake graphite in treating processes.

The objective of the invention is to: a kind of anode oxidative treatment method and device of producing expansible black lead is provided, a kind of anodic oxidation treatment system that flows cast, produce with this system, not only the change degree is even between gas producing formation, yield is high, and the serialization of production process easy to implement and automatization.The characteristics of technological thought of the present invention are: make the interlayer degree in nearly cathodic area conform to requirement, also be that the highest a part of expansible black lead of interlayer degree constantly leaves the anodic oxidation treatment district in time in instant whole anodic oxidation treatment system, as long as this leave be since the natural flake graphite raw material under the promotion of power, order is through the positive column after constantly entering in the treatment system outside system, the anode and cathode intermediate zone ... accept the result of oxidation, just can use the uniform expansible black lead of change degree between this system productive zone, realize charging, the serialization of discharging process.Again because actual bearer (electric load) ability of the inventive method and device is bigger, and operating voltage is lower, so have than much higher productivity or the power saving of prior art or obtain advantages such as power saving and higher productivity simultaneously.

According to above-mentioned technological thought characteristics, method and apparatus proposed by the invention comprises following part:

In the inventive method and device, anode 6, it can be made with the pipe of stainless steel and other metal materials.It can be not only as the acceptor of accepting conduction electron, play loading, transportation again, the mixture of water conservancy diversion electrochemical liquid (it can be solution or their mixture solutions such as sulfuric acid, nitric acid, phosphoric acid and some organic acid, metal-salt) and graphite (is called for short mixture, down together the part of) total pipeline.In this case, the anode of anodic oxidation treatment power supply can directly be connected on the outer wall as the anodic pipeline; Anode 6 also can be that at least one section metal tube or at least one tinsel or radial lamellar body or their combination are installed in outer tube (metal or nonmetal making); Perhaps anode 6 is made of jointly this part of aforementioned total pipeline and that part in the pipeline.The orientation of all positive plates surface (promptly with the perpendicular direction of surface normal) and mixture flowing to there is 7 unanimous on the whole at least.Distance between all anode body surface and has conductor to connect between 1 millimeter to 30 millimeters each other, they in the length of longshore current on 7 direction greater than 2 millimeters.Mixture under hydraulic pressure or air pressure or mechanical isodynamic driving, by entering outside the anodic oxidation treatment system and positive column by oxide treatment, flows to the oxide treatment district of nearly negative electrode in anodic oxidation treatment.Negative electrode is positioned at the overall opposite of anode, and it is divided into main cathode 1 again and negative electrode 3 two parts in the outside are formed.Negative electrode 1,3 is respectively to be made of one section metal tube or at least one tinsel, plate, piece or their composition or other shapes at least.Distance between all cathodes and has conductor to connect between 0.5 millimeter to 30 millimeters each other, and their length on the vertical line direction is greater than 2 millimeters.Their surface orientation is beneficial to row's ease of the bubble that negative electrode produces in electrochemical treatment process.Negative electrode 1,3 respectively and have one deck insulation net 2 with holes between the mixture at least separates crystalline flake graphite in the mixture and negative electrode, is principle so that the electronics conduction not to take place, and at this, the stream pipe of treatment system is to be made of tubular space between the negative electrode 1,3.It is at least straight tube-like or stream pipe caliber upwards the time enlarge to some extent.Requiring lowly slightly, or in the not too big anodic oxidation system of size, can save in two negative electrodes.The top of outer tube anode (the diagonal line hatches part of anode 6) and one section insulation tube 4 (* * the line dash area) link.The length P of parts 4 is between 2 to 30 millimeters, and go to the bottom and the outside of outside negative electrode 3 also can be made with metal.But when the outside of outside negative electrode 3 was metal, its outer side should have the hole insulant.Behind the oxide treatment district of mixture by nearly negative electrode, finally leave the oxide treatment district, just leave the stream tube terminal, enter collector 5.In the large size anodic oxidation treatment equipment of the inventive method, under the situation of using high current density (at this moment voltage is also high), should consider in the treatment system to produce too much ohm heat, and, determine scale, mode and the installation site of cooling system according to its size.As a special case: can constantly upgrade by the electrochemical liquid that is filled between each pipe of anticathode, plate, this not only helps heat release and favourable adjusting technology running status.Under the lower situations such as sulphuric acid soln of working concentration, containing the reversible circulation component during the power supply of anodic oxidation treatment is supplied with provides the cathodic reduction function.

Advantage that the present invention is compared with prior art had and positively effect:

1. the present invention can obtain the uniform quality products of interlayer degree.In treatment system of the present invention, reach that a part of crystalline flake graphite of interlayer degree of design, will leave treatment zone continuously, and make way for the follow-up person of the interlayer degree of the design that does not reach, thereby not as prior art institute inherent ununiformity shortcoming, so the product quality is evenly good.

2. the present invention has higher yield than prior art.Prior art has acceptable average expansion multiplying power for natural flake graphite is reached, for example, its corresponding specific volume after expansion reaches 200 milliliters/gram, with the acceptable ununiformity, interpole gap is selected near 7.5 centimetres when 2000 square centimeters of positive plate areas according to qualifications, therefore, the crystalline flake graphite amount of each anodic oxidation treatment just is restricted; The according to qualifications value of current density is about 15 milliamperes/square centimeter in the case, and then the yield between the every pair of cathode-anode plate is 4 kilograms/square metre hours, and is that a groove one trough carries out, so production efficiency is low.And in treatment system of the present invention, because interlayer degree graphite up to standard, i.e. getting out while you can of the graphite of those high polarized potentials, overall polarized potential is than low in the general method in the treatment system.In addition, successive input and output material mode, there is no need to consider what of charging of treatment system, can reduce the effective mean distance between negative and positive two utmost points much like this, and effective in the present invention metal anode area has increased many, all this all multifactor combinations, make and allow on the cross section with the mixture flow direction by very high current density (current density of mentioning below all herewith defines), for example, when the current density of first-class pipe is 200 milliamperes/square centimeter, operating voltage when continous-stable is handled discharging is 2.05 volts, and higher yield is so not only arranged, and power saving.When current density reaches 1800 milliamperes/square centimeter, also only 3.60 volts of the operating voltage during its continuous discharging.Certainly can also further improve current density increasing yield, but the current consumption of handling unit weight graphite at that time will be higher than the value according to qualifications of prior art gradually.When current density is 1000 milliamperes/square centimeter, voltage is 2.90 volts, and then the yield of system is: 22.2 gram/square centimeters hour, and the product institute consuming electric power of unit weight only is 83% of a prior art.

3. two interpolar operating voltage are vicissitudinous in the prior art, need regulate.Among the present invention, only outside the initial time needs adjusting in short-term that each long-time continuous is produced, in continuous flow procedure, current/voltage remains unchanged, laborsaving like this or province's expense.

Between the plan layer of product the change degree can the real-time online adjustment, change.

Since the continuous flow of mixture under certain pressure to the metal anode table and certain is cleaned with water and regeneration function, the polarized action on metal anode surface is more light than what had in the prior art.

6. improve workman's labor condition greatly, be easy to the comprehensive automation of production process, the cost of equipment of production unit weight product, production site area descend.

The continuously feeding that the present invention once implemented with the example of the packaged unit of discharging is: anode 6 is 65 millimeters stainless guiding principle pipe by one section internal diameter and places in it some to become the stainless steel flat plate of column radiation (its radiation center line is consistent with system axis) to constitute that (but not every flat board is all begun to radiate by the center, but from being that send in the different posts garden of medullary ray with the system axis, they all terminate in internal diameter is on 65 millimeters the outer tube, distance between them is controlled near 5 millimeters there, the closest range between palette～2 millimeter).The length of their longshore currents on 7 directions is 50 millimeters; The length P=3 millimeter of parts 4; Main cathode 1, similar with anode, only towards the anodic part convex of saying so on the whole; Outside negative electrode 3 also is that cylindricality is radial, and the distance of its paraxial line end and system axis is 33 millimeters, and the plate face is perpendicular to the ground, has conductor to connect each other; The spiral charging pump that can push mixture the special use of reactive system is equipped with in anode 6 belows.Add voltage at described cathode and anode two ends, when voltage when 2.05 volts are increased to 3.60 volts, the working current of system is increased to 57 amperes from 6.5 amperes.For specific volume after utilizing the production of this device to expand is the expansible black lead of 80～300 milliliters/gram, handles the power consumption of 1 liter of 599 graphite, is advisable with 20～70 ampere hours.

Claims (3)

1. an anode oxidative treatment method and device of producing expansible black lead, it is characterized in that: the anodic oxidation treatment system flows cast, the mixture that is filled with graphite and electrochemical liquid in the stream pipe in positive column regulating YIN and YANG two interpolar districts (is called for short mixture, down together), extremely go up making alive two, galvanization, mixture is under the effect of air pressure or hydraulic pressure or mechanical force simultaneously, by the outer system that enters of pipe, near the anode by system, the graphite in the mixture begins to accept oxide treatment, and leads to gradually near the negative electrode of system, after reaching the interlayer degree of setting, leave the cathodic area of system, enter collector.

2. the anode described in claim 1 is characterized in that: it is a metal tube or is made up of at least one metal tube and at least one metal sheet, sheet that the surface orientation of these pipes, plate and the flow direction of mixture are unanimous on the whole at least.

3. the negative electrode described in claim 1, it is characterized in that: it is made up of main cathode and outside negative electrode two parts or main cathode or outside negative electrode, they are respectively at least by a metal tube or be that a metal sheet, sheet, piece or their composition constitute at least, and these pipe, sheet, plate, piece and mixture boundarys that constitute negative electrodes are equipped with the hole net that insulate the graphite in negative electrode and the mixture is separated.