A production method of high-purity activated carbon for preparing electronic-grade hydrogen peroxide

Abstract

The application relates to the technical field of wet electronic chemicals, and discloses a production method of high-purity activated carbon for preparing electronic-grade hydrogen peroxide, and the specific preparation process steps are as follows: step one: high-quality coal liquefied pitch is used as an extraction agent, 1000 kg of high-quality coal liquefied pitch is added into 2000 kg of refined naphthalene, 150 kg of anhydrous aluminum chloride is further added, and stirring reaction is carried out under oil bath at 180 DEG C for 120 min; step two: solid-liquid separation is realized by using a horizontal solid-liquid centrifuge, and the solid phase is discarded, more than 90% of the anhydrous aluminum chloride is removed, the ash content of the activated carbon is less than 0.3%, and the quality is stable; in the primary treatment of preparing the electronic-grade hydrogen peroxide, more than 99% of organic impurities, more than 95% of inorganic impurities and the like in industrial hydrogen peroxide can be removed, the organic impurities are aromatic hydrocarbons, octanol, tri-octyl phosphate, anthraquinone compounds and phenols, the inorganic impurities are calcium, sodium, potassium, iron, aluminum and silicon, the adsorption capacity of the activated carbon does not obviously decrease after being regenerated for 5 times, and the use cost of customers is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wet electronic chemicals, in particular to a production method of high-purity activated carbon for preparing electronic-grade hydrogen peroxide. BACKGROUND

[0002] Electronic-grade hydrogen peroxide is a key basic wet electronic chemical necessary for large-scale integrated circuit production process, which is mainly used as a cleaning agent, a corrosive agent and a remover of photoresist for large-scale integrated circuits. The purity of the electronic-grade hydrogen peroxide has an important influence on the yield, electrical performance and reliability of the finished product of the large-scale integrated circuit. At present, the development and production of electronic-grade hydrogen peroxide have made certain progress in China, but compared with the international advanced level, there is still a big gap, and the production scale is small, and high-end products still rely on imports. The industrialized purification technology for preparing electronic-grade hydrogen peroxide is a commercial secret of foreign large manufacturers and is strictly kept secret. From the existing literature, it can be seen that the preparation of electronic-grade hydrogen peroxide may be a multi-element operation integration of rectification, adsorption, ion exchange, extraction, crystallization, membrane separation and the like, and the activated carbon adsorption impurity removal is the most suitable preliminary impurity removal method for industrial-grade hydrogen peroxide. The impurities in the hydrogen peroxide solution are removed by the adsorption capacity of the solid adsorbent without phase change, without external driving force, so that the equipment and process are simple, the production conditions are mild, and the operation is convenient. It is widely used in the production process of electronic-grade hydrogen peroxide. The activated carbon with low ash content and high purity is particularly important for the preparation of electronic-grade hydrogen peroxide. SUMMARY

[0003] In view of the deficiencies of the prior art, the present application provides a production method of high-purity activated carbon for preparing electronic-grade hydrogen peroxide, which has the advantages of improvement, low ash content and multiple regeneration, and solves the problems raised in the background art.

[0004] In order to achieve the above-mentioned improvement, low ash content and multiple regeneration, the present application provides the following technical scheme: a production method of high-purity activated carbon for preparing electronic-grade hydrogen peroxide, the specific preparation process steps are as follows:

[0005] Step one: a high-quality coal liquefied pitch is used, 1000 kg of high-quality coal liquefied pitch is added with 2000 kg of refined naphthalene, and then 150 kg of anhydrous aluminum chloride is added, and stirring reaction is carried out at 180℃ oil bath for 120 min;

[0006] Step two: immediately use a horizontal solid-liquid centrifuge to realize solid-liquid separation, and discard the solid phase, and more than 90% of the aluminum chloride is removed;

[0007] Step three: when the liquid phase is cooled to 95℃, 5000 kg of 5% hydrochloric acid solution is added to stir and wash the liquid phase of the previous step, and the water phase is discarded, and most of the remaining aluminum chloride and part of the inorganic impurities such as calcium, sodium, potassium and iron are removed.

[0008] Step four: the liquid of the above step is cooled to room temperature to obtain naphthalene pitch, and the naphthalene pitch is made into balls with a diameter of about 3 cm;

[0009] Step five: the naphthalene pitch ball is placed into a converter, dry chlorine gas is introduced at 1200 DEG C for roasting for 90 min, hydrogen elements in the naphthalene pitch react with the dry chlorine gas to generate hydrogen chloride gas which is absorbed by water, and small-pored high-purity activated carbon is generated at the same time;

[0010] Step six: the activated carbon is cooled and crushed to more than 300 mesh;

[0011] Step seven: the activated carbon powder is stirred and washed in a mixed acid solution of 10% dilute hydrochloric acid and 3% dilute hydrofluoric acid at 90 DEG C for 60 min under the condition of a solid-liquid ratio of 1:3, and the activated carbon powder is washed 3 times with pure water under the condition of a solid-water ratio of 1:8, and impurities such as silicon, iron and aluminum are basically removed;

[0012] Step eight: the activated carbon powder is cleaned and purified by using ultra-pure water under the condition of a solid-water ratio of 1:10 and a temperature of 150 DEG C in a steam pressure kettle;

[0013] Step nine: the activated carbon powder is dried at 120 DEG C under a nitrogen atmosphere to obtain finished high-purity activated carbon;

[0014] Further; the ash content of the ultra-pure activated carbon is less than 0.3%, and the pore size is distributed between 0.05 um and 0.2 um;

[0015] Further; when the adsorption capacity of the ultra-pure activated carbon obviously decreases in the use process of purifying industrial hydrogen peroxide, the activated carbon is regenerated from the above step 5 to step 9, that is, the activated carbon is added with a small amount of high-purity binder containing only carbon-hydrogen-oxygen to make a ball, and the regeneration process is started by introducing dry chlorine gas at 1200 DEG C for roasting;

[0016] Further; after the ultra-pure activated carbon is regenerated for 5 times, the adsorption capacity of the activated carbon is still more than 83% of the initial adsorption capacity.

[0017] Compared with the prior art, the beneficial effects of the present application are:

[0018] The ash content of the activated carbon is less than 0.3% and the quality is stable, and in the primary treatment of preparing electronic-grade hydrogen peroxide, more than 99% of organic impurities such as aromatic hydrocarbons, octanol, tricresyl phosphate, anthraquinone compounds and phenols in industrial hydrogen peroxide can be effectively removed, and more than 95% of inorganic impurities such as calcium, sodium, potassium, iron, aluminum and silicon in industrial hydrogen peroxide can be removed; the adsorption capacity of the activated carbon does not obviously decrease after being regenerated for 5 times, and the use cost of customers is greatly reduced. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the protection scope of the present application.

[0020] In the embodiments of the present application, a production method for preparing high-purity activated carbon for electronic-grade hydrogen peroxide is provided, and the specific preparation process steps are as follows:

[0021] Step one: 1000 kg of high-quality coal liquefied pitch is added with 2000 kg of refined naphthalene as an extractant, and 150 kg of anhydrous aluminum chloride is further added, and then the mixture is stirred and reacted at 180°C for 120 min under oil bath;

[0022] Step two: a horizontal solid-liquid centrifuge is immediately used to realize solid-liquid separation, and the solid phase is discarded, and more than 90% of the aluminum chloride is removed;

[0023] Step three: when the liquid phase is cooled to 95°C, 5000 kg of 5% hydrochloric acid solution is added to stir and wash the liquid phase in the previous step, and the water phase is discarded, and most of the remaining aluminum chloride and part of the inorganic impurities such as calcium, sodium, potassium and iron are removed.

[0024] Step four: the liquid phase in the previous step is cooled to room temperature to obtain naphthalene pitch, and the naphthalene pitch is made into balls with a diameter of about 3 cm;

[0025] Step five: the naphthalene pitch ball is placed into a converter, dry chlorine gas is introduced at 1200°C for roasting for 90 min, hydrogen elements in the naphthalene pitch react with the dry chlorine gas to generate hydrogen chloride gas which is absorbed by water, and high-purity activated carbon with small pore size is simultaneously generated;

[0026] Step six: the above activated carbon is cooled and crushed to more than 300 mesh;

[0027] Step seven: the activated carbon powder is stirred and washed at 90°C for 60 min in a mixed acid solution of 10% dilute hydrochloric acid and 3% dilute hydrofluoric acid with a solid-liquid ratio of 1:3, and the activated carbon powder is washed three times with pure water with a solid-water ratio of 1:8, and the impurities such as silicon, iron and aluminum are basically removed;

[0028] Step eight: the above activated carbon powder is cleaned for 60 min in an ultra-pure water in a steam pressure kettle under the condition of a solid-water ratio of 1:10 and a temperature of 150°C, so as to further clean and purify the activated carbon;

[0029] Step nine: the above activated carbon powder is dried at 120°C under a nitrogen atmosphere to obtain finished high-purity activated carbon;

[0030] The ultra-pure activated carbon has ash content less than 0.3%, and pore size is distributed between 0.05um and 0.2um; in the use process of purifying industrial hydrogen peroxide, when the adsorption capacity of the ultra-pure activated carbon obviously decreases, the activated carbon is regenerated from the fifth step to the ninth step, that is, the activated carbon is added with a small amount of high-purity binder containing only carbon-hydrogen-oxygen, and the regeneration process is started by roasting the ball at 1200 DEG C with dry chlorine; after the ultra-pure activated carbon is regenerated for 5 times, the adsorption capacity of the activated carbon is still more than 83% of the initial adsorption capacity.

[0031] When the present application works: a high-quality coal liquefaction pitch is used, refined naphthalene is used as an extractant, 1000 kg of high-quality coal liquefaction pitch is added with 2500 kg of refined naphthalene, and then 130 kg of anhydrous aluminum chloride is added, and the mixture is stirred and reacted under oil bath at 200 DEG C for 120 min; without cooling, solid-liquid separation is realized by using a horizontal solid-liquid centrifuge, and the solid phase is discarded; when the liquid phase is cooled to 90 DEG C, 6000 kg of 5% reagent-grade hydrochloric acid solution is added to stir and wash the liquid phase in the previous step, and the aqueous phase is discarded; the liquid phase in the previous step is cooled to room temperature to obtain soft solid naphthalene pitch, the naphthalene pitch is made into balls with a diameter of about 3 cm; the naphthalene pitch balls are placed into a converter, dry chlorine gas is introduced at 1300 DEG C for roasting for 90 min, the hydrogen element in the naphthalene pitch reacts with the dry chlorine gas to generate hydrogen chloride gas which is absorbed by water, the activated carbon is cooled and then crushed to more than 300 mesh, the activated carbon powder is stirred and washed with a mixed acid solution of 8% dilute hydrochloric acid and 3% dilute hydrofluoric acid at 90 DEG C for 60 min under the condition that the solid-liquid ratio is 1:3, and then filtered, the activated carbon powder is washed with pure water for 3 times under the condition that the solid-water ratio is 1:8, the activated carbon powder is cleaned and purified by using ultra-pure water under the condition that the solid-water ratio is 1:12, the temperature is 160 DEG C, and the cleaning time is 60 min, the activated carbon is dried at 130 DEG C under a nitrogen atmosphere, and finally the high-purity activated carbon is obtained; according to quality and various instrument detections, the ash content of the high-purity activated carbon is less than 0.25%, the contents of silicon, aluminum and boron are all less than 0.02%, and the contents of potassium, sodium, calcium, magnesium, iron and sulfur are all less than 0.01%.

[0032] The above only describes the preferred embodiments of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A process for the production of high purity activated carbon for the production of electronic grade hydrogen peroxide, characterized by: The specific preparation process steps are as follows: Step one: using a high-quality coal liquefaction pitch, taking refined naphthalene as the extractant, 1000 kg of high-quality coal liquefaction pitch is added with 2000 kg of refined naphthalene, and then 150 kg of anhydrous aluminum chloride is added, and stirring reaction is carried out at 180°C oil bath for 120 min; Step two: immediately use a horizontal solid-liquid centrifuge to realize solid-liquid separation, and discard the solid phase, and more than 90% of the aluminum chloride is removed; Step three: when the liquid phase is cooled to 95°C, 5000 kg of 5% hydrochloric acid solution is added to stir and wash the liquid phase of the previous step, and the water phase is discarded, and most of the remaining aluminum chloride and part of the calcium, sodium, potassium and iron impurities are removed; Step four: the liquid phase of the previous step is cooled to room temperature to obtain naphthalene pitch, and the naphthalene pitch is ball-shaped, and the ball diameter is about 3 cm; Step five: the naphthalene pitch ball is placed in a converter, dry chlorine gas is introduced at 1200°C for roasting for 90 min, hydrogen elements in the naphthalene pitch generate hydrogen chloride gas with dry chlorine gas and are absorbed by water, and high-purity activated carbon with small pore size is generated at the same time; Step six: the above activated carbon is cooled and finely ground to more than 300 mesh; Step seven: under the conditions of 10% dilute hydrochloric acid and 3% dilute hydrofluoric acid mixed acid solution with a solid-liquid ratio of 1:3, stirring and washing the activated carbon powder at 90°C for 60 min, and the solid-liquid ratio is 1:8, and the above activated carbon powder is washed with pure water for 3 times, and the silicon, iron and aluminum impurities are basically removed; Step eight: the above activated carbon powder is cleaned and purified with ultrapure water under the conditions of solid-liquid ratio of 1:10 in a steam pressure kettle at 150°C for 60 min; Step nine: the above activated carbon powder is dried at 120°C under nitrogen atmosphere to obtain finished high-purity activated carbon.

2. The production method of high purity activated carbon for producing electronic grade hydrogen peroxide according to claim 1, characterized in that: The ash content of the high-purity activated carbon is less than 0.3%, and the pore size is distributed between 0.05um and 0.2um.

3. The production method of high purity activated carbon for producing electronic grade hydrogen peroxide according to claim 1, characterized in that: In the use process of purifying industrial hydrogen peroxide, when the adsorption capacity of the high-purity activated carbon decreases obviously, the activated carbon is regenerated from the above steps 5 to 9, that is, the activated carbon is added with a small amount of high-purity binder containing only carbon-hydrogen-oxygen to form a ball, and the regeneration process is started by introducing dry chlorine gas at 1200°C.

4. The production method of high-purity activated carbon for producing electronic-grade hydrogen peroxide according to claim 1, characterized in that: After the high-purity activated carbon is regenerated for 5 times, the adsorption capacity of the activated carbon is still more than 83% of the initial adsorption capacity.