阅读说明：本技术 木质素在制备锂电池石墨负极材料中的应用 (Lignin is preparing the application in lithium battery graphite cathode material ) 是由 陈都 李振宁 于 2019-08-20 设计创作，主要内容包括：本发明公开了木质素在制备锂电池石墨负极材料中的应用,所述木质素的制备过程为：生物质在酸性溶液中进行水解反应后的反应液即为水解后料液,在所得水解后料液中加入2-10体积倍的水,搅拌,有固体析出,过滤,滤渣经清水洗涤后干燥,即得所述木质素。通过本发明的方法能将生物质完全液化水解,然后提取生物质液化水解生成的木质素,该木质素的芳香度高、含硫量低,在应用于制备锂电池石墨负极材料时,有较好的首次放电比容量、首次库伦效率、粉末压实密度、石墨化度和固定碳含量等性能参数。(The invention discloses lignin to prepare the application in lithium battery graphite cathode material, the preparation process of the lignin are as follows: it is feed liquid after hydrolyzing that the reaction solution after reaction, which is hydrolyzed, in biomass in an acidic solution, the water of 2-10 volume times is added in feed liquid after gained hydrolysis, stirring, there is solid precipitation, filtering, filter residue are dried after clear water washs to get the lignin.By means of the present invention can liquefy completely biomass hydrolysis, then the lignin that biomass liquefying hydrolysis generates is extracted, the aromaticity of the lignin is high, sulfur content is low, when being applied to prepare lithium battery graphite cathode material, there are preferable first discharge specific capacity, for the first time performance parameters such as coulombic efficiency, powder compacted density, degree of graphitization and fixed carbon content.)

1. lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that the preparation process of the lignin Are as follows: it is feed liquid after hydrolyzing that the reaction solution after reaction, which is hydrolyzed, in biomass in an acidic solution, after gained hydrolysis in feed liquid The water of 2-10 volume times is added, stirring has solid precipitation, filters, and filter residue is dried after clear water washs to get the lignin.

2. lignin as described in claim 1 is preparing the application in lithium battery graphite cathode material, it is characterised in that with wood The step of quality is raw material, prepares lithium battery graphite cathode material are as follows:

1) lignin is mixed with stabiliser solution by 1: 2 ~ 12 mass ratio, stands and stablizes 3 ~ 6 hours at 40 ~ 70 DEG C Afterwards, it filters, filter residue and drying obtains stablizing lignin；

2) lignin will be stablized obtained by step 1) to be placed in rotary kiln, under nitrogen protection atmosphere, and in 1200 ~ 1500 DEG C of temperature Lower calcining 2 ~ 4 hours, obtains calcined lignin；

3) calcined lignin obtained by step 2 is placed in graphitizing furnace, under argon atmosphere, and in 2500 ~ 2800 DEG C temperature lower calcination 3 ~ 15 hours, subsequent cooled to room temperature was to get the lithium battery graphite cathode material.

3. lignin as claimed in claim 2 is preparing the application in lithium battery graphite cathode material, it is characterised in that described Stabiliser solution is the ammonium dibasic phosphate aqueous solution of mass concentration 10% ~ 20%.

4. lignin as described in claim 1 is preparing the application in lithium battery graphite cathode material, it is characterised in that described The reaction solution after reaction is hydrolyzed in biomass in an acidic solution, is prepared according to following procedure:

S1: biological particles be added reaction kettle in, under anaerobic state be added water cosolvent, heated under stirring 150 DEG C- 220 DEG C, lewis acid is added, reaction 20-40 minutes, the biomass mixed liquor after must hydrolyzing is hydrolyzed；

S2: into the biomass mixed liquor of step S1 plus alkali neutralization adjusts pH to 4.5-8, and cooled and filtered removes what neutralization obtained Ash content in sediment and biomass is to get the reaction solution.

5. lignin as claimed in claim 4 is preparing the application in lithium battery graphite cathode material, it is characterised in that step For biological particles water content less than 8%, grain diameter is less than 25mm in S1, and biomass is timber, stalk, paper product, pine, grass Class, rice husk, bagasse, cotton, jute, flax, bamboo, sisal hemp, abaca, straw, any one or a few mixing in corncob Object.

6. lignin as claimed in claim 4 is preparing the application in lithium battery graphite cathode material, it is characterised in that step In S1, water and tetrahydrofuran mixed liquor that water cosolvent is mass ratio 1:1-1:5.

7. lignin as claimed in claim 4 is preparing the application in lithium battery graphite cathode material, it is characterised in that step In S1, the mass ratio of biomass and water cosolvent is 1: 2-7；The lewis acid is sulfuric acid, hydrochloric acid, at least one in nitric acid Kind, the lewis acidic quality is the 0.3%-3% of water cosolvent quality.

Technical field

The present invention relates to lignin to prepare the application in lithium battery graphite cathode material.

Background technique

Mainly mass storage is in the life with us in the form of agricultural and forest trimmings for biomass, domestic biomass Waste material derives from the stalk of the crops such as soya corn, while Furniture Factory also generates raw a large amount of sawdust during manufacturing furniture And wood shavings, it deals with improperly and will also result in environmental pollution.Chinese stalk theoretical yield collects stock number up to 8.84 hundred million tons within 2017 700,000,000 tons big, wherein arriving rice straw 25%, wheat straw 18.3%, corn stalk accounts for about 33%, and cotton straw 3%, rape flower and peanut about turn 4.4%. It is mainly distributed on Liaoning, Jilin, 13, Heilungkiang etc. major grain producing area, stalk resource amount accounted for 70% of total amount or more.

Usual agricultural biomass waste material has several processing methods: 1) by on-site incineration returning to the field, but causing serious Air pollution, so country is special to put into effect " stalk prohibit burn and comprehensive utilization management method ", to forbid open incineration stalk.2) Biomass power generation, agricultural biomass waste material direct plunge into electricity generation boiler.Although this method solves pollution caused by on-site incineration Problem, but biomass economy rate is low.3) biomass through pyrolysis method (such as Chinese patent 201210048116.3, by biomass thermal Cracking process generate biomass coke tar): under anoxic condition by (400-600 degrees Celsius) of high temperature processing, make biomass decomposition at Biomass charcoal, biomass coke tar or pyrolysis gas, this method effectively make biomass fast decoupled, generate it is different can Use fuel.Can do that fuel uses mainly: the pyrolysis gas of biomass and biomass coke tar of low heat value.Although this method realizes Biomass is to the conversion of bio-fuel, but the added value of biofuel products is lower.

But in the prior art, there are no about " using biomass as starting material, preparing the lithium battery graphite of high added value The document report of negative electrode material ".And in the prior art, generally use petroleum coke as the raw material for preparing artificial graphite, still Petroleum coke has the following deficiencies: 1, content of beary metal height, 2, sulfur content height.Secondly, natural graphite is also as cathode of lithium battery The common used material of material, but the impurity in natural material is more, separation and Extraction impurity needs to keep away using toxic chlorine That exempts from increases the complexity of technique.Furthermore petroleum and natural graphite are all non-renewable resources, petroleum coke is largely used Global warming can be brought, the problems such as environmental pollution.

Therefore, the novel new method for preparing lithium battery graphite cathode material of one kind is developed to be of great significance.

Summary of the invention

For above-mentioned technical problem of the existing technology, the purpose of the present invention is to provide lignin to prepare lithium battery Application in graphite cathode material, by means of the present invention can liquefy completely biomass hydrolysis, then extract biomass liquid Change the lignin that hydrolysis generates, the aromaticity of the lignin is high, sulfur content is low, is being applied to prepare lithium battery graphite cathode material When, there is preferable performance parameter.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that the system of the lignin Standby process are as follows: it is feed liquid after hydrolyzing that the reaction solution after reaction, which is hydrolyzed, in biomass in an acidic solution, after gained hydrolysis The water of 2-10 volume times is added in feed liquid, stirring has solid precipitation, filters, and filter residue is dried after clear water washs to get the wood Quality.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that with lignin be original The step of expecting, preparing lithium battery graphite cathode material are as follows:

1) lignin is mixed with stabiliser solution by 1: 2 ~ 12 mass ratio, stands and stablizes 3 ~ 6 hours at 40 ~ 70 DEG C Afterwards, it filters, filter residue and drying obtains stablizing lignin；

2) lignin will be stablized obtained by step 1) to be placed in rotary kiln, under nitrogen protection atmosphere, and in 1200 ~ 1500 DEG C of temperature Lower calcining 2 ~ 4 hours, obtains calcined lignin；

3) calcined lignin obtained by step 2 is placed in graphitizing furnace, under argon atmosphere, and in 2500 ~ 2800 DEG C temperature lower calcination 3 ~ 15 hours, subsequent cooled to room temperature was to get the lithium battery graphite cathode material.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that the stabiliser solution For the ammonium dibasic phosphate aqueous solution of mass concentration 10% ~ 20%.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that the biomass is in acid Property solution in be hydrolyzed reaction after reaction solution, be to be prepared according to following procedure:

S1: biological particles be added reaction kettle in, under anaerobic state be added water cosolvent, heated under stirring 150 DEG C- 220 DEG C, lewis acid is added, reaction 20-40 minutes, the biomass mixed liquor after must hydrolyzing is hydrolyzed；

S2: into the biomass mixed liquor of step S1 plus alkali neutralization adjusts pH to 4.5-8, and cooled and filtered removes what neutralization obtained Ash content in sediment and biomass is to get the reaction solution.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that biomass in step S1 For particle water content less than 8%, grain diameter is less than 25mm, and biomass is timber, stalk, paper product, pine, careless class, rice husk, sweet Bagasse, cotton, jute, flax, bamboo, sisal hemp, abaca, straw, any one or a few mixture in corncob.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that in step S1, water is total The water and tetrahydrofuran mixed liquor that solvent is mass ratio 1:1-1:5.

The lignin is preparing the application in lithium battery graphite cathode material, it is characterised in that in step S1, biology The mass ratio of matter and water cosolvent is 1: 2-7；The lewis acid is at least one of sulfuric acid, hydrochloric acid, nitric acid, the road The quality of Lewis acid is the 0.3%-3% of water cosolvent quality.

Compared with the existing technology, the beneficial effect that the present invention obtains is:

1) reaction solution after reaction is hydrolyzed in an acidic solution and is denoted as feed liquid after hydrolysis for biomass, after the hydrolysis in feed liquid Such as containing biomass hydrolysate: the lignin after the sugar of C5-C6, furfural, levulic acid and hydrolysis, the wood after the hydrolysis Quality is adsorption.A certain amount of water mixing is added after to hydrolysis in feed liquid, lignin can be reduced in the water Solubility after solution in feed liquid, and then (biomass hydrolysates such as sugar, furfural, levulic acid of C5-C6 are basic for precipitation lignin Dissolution in feed liquid, can be used as the use of the purposes such as liquid fuel, plant nutrition liquid after hydrolyzing.Wherein the precipitation purity of lignin and Quality is higher, is conducive to prepare downstream high value-added product).The lignin of precipitation is after clear water is cleaned and dried, institute Lignin product aromaticity it is higher and the sulfur content of gained lignin, ash content are lower, it is high to be particularly suitable for preparation downstream The graphite material of added value.

2) when the lignin that the present invention extracts is used to prepare lithium battery graphite cathode material, there is the ratio that preferably discharges for the first time Capacity, for the first time coulombic efficiency, powder compacted density, the performance parameter of degree of graphitization and fixed carbon content, meet cathode of lithium battery The use standard of material.Secondly, method of the invention can reduce lithium battery efficiently using renewable resources such as biomass straws Consumption of the negative electrode material to natural resources improves economic benefit while rate reduces environmental pollution.

Specific embodiment

The present invention is further explained in the light of specific embodiments, but the scope of protection of the present invention is not limited thereto.