KR20160137751A - Method of preparing hydrochloric acid from polyvinyl chloride and method of dehydrochlorinating waste polyvinyl chloride - Google Patents

Abstract

The present invention relates to a method for preparing hydrochloric acid from polyvinyl chloride and a method of treating waste polyvinyl chloride and, more specifically, to a method for preparing hydrochloric acid from polyvinyl chloride and a method of treating waste polyvinyl chloride by using metal oxide or carbon nitride catalysts in a liquid reaction condition. According to the present invention, dechlorination reaction of waste polyvinyl chloride can be effectively performed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing hydrochloric acid from polyvinyl chloride and a method for treating dehydrochlorinated polyvinyl chloride,

The present invention relates to a process for producing hydrochloric acid from polyvinyl chloride and a process for treating dechlorination of waste polyvinyl chloride, and more particularly, to a process for producing hydrochloric acid from polyvinyl chloride using a metal oxide or a carbon nitride catalyst under the liquid- And a method of dehydrochlorination of waste polyvinyl chloride.

The development of a new concept of waste plastics processing technology has become increasingly important due to the increase of waste plastics worldwide and the subsequent filling of waste and the saturation of incineration facilities. Particularly, in order to increase the recyclability of waste PVC, it is necessary to use recycled materials such as recycled materials or recycled waste plastics (MR) There is an increasing need to develop raw material technology for waste resources. In addition, large quantities of waste PVC are currently being imported into the country in Japan, China and Europe, and most of them are recycled for the production of pipes for sewage pipes, general pipes and conduits. And the development of technology for recycling of materials and chemical recycling is further needed.

PVC has different contents from additive in different uses. Therefore, in case of material recycling, there is a problem of property deterioration. In Korea, only waste PVC, which was used as a pipe and window, is collected. There is no research on the development of chemical recycling technology to utilize.

In general, the recycling technology of waste resources used is the recycling (MR) that produces the product through the pulverization, washing and classification of the particle size of the collected waste plastics, and the chemical recycle (pyrolysis, chemical decomposition and purification) It can be divided into chemical recycling (CR) to be recycled and energy recycling (ER) to be used as an energy source through combustion and incineration.

On the other hand, the PVC recycling volume in Europe in 2007 was 113,000 tons / year, of which the UK reportedly recycled 42,000 tons / year, Germany 35,000 tons / year and France 13,000 tons / The recycling rate of waste PVC is continuously increasing. In Japan, waste plastics are compulsory to be recycled according to the Environmental Law, and regulated to reuse, reduce and recycle waste resources in accordance with the Law for Promotion of Effective Utilization of Resources.

As a conventional PVC recycling technology, the Solvay process, commercialized in 2002, is a vinyl loop dissolution method that is a physical recycling technique, after pulverizing waste PVC scraps and then dissolving them in special solvents. Solvay Plastics operates a 10,000-tonne / year facility and the Kobelco Vinyl loop East process in Japan operates a 26,000-ton / year facility in 2006 , It is reported that the operation of the above process has a reduction effect of about 40% of carbon dioxide (CO ₂ ) and an energy reduction effect of about 70%. Wacker Chemie of Germany has reported that it has developed a process of directly recovering chlorine gas (HCl) from waste PVC through rotary kiln dechlorination [Polymer Science and Technology 13 (2002) 332-341]. Yoshioka Group also introduces the treatment technology of waste PVC through the reaction of producing oxalic acid and benzenecarboxylic acid as oxidizing compounds through the oxidation reaction using sodium hydroxide (NaOH) at 150 ~ 260 ° C using waste PVC. [T. Yoshioka, S. Yasuda, K. Furukawa, T. Sato, A. Okuwaki, Proc. 2 ^nd Int. Symp. East Asian Resources Recycling Technol., Seoul, October 14-16, p. 100 (1993)].

In addition, the chemical conversion of waste PVC by pyrolysis changes the selectivity of gas and oil depending on the pyrolysis temperature. In the reaction temperature range of 250 ~ 400 ℃, useful hydrocarbons and benzene derivatives (benzene- derivatives (see US Patent No. WO 2010/139997 A2 and Fuel Processing Technology 92 (2011) 253-260). In addition, in the case of adding an oxide such as iron oxide (FeO _x ) during the pyrolysis of waste PVC, there is a report that the amount of hydrochloric acid gas is reduced, thereby reducing environmental pollution and corrosion, and increasing the amount of oil produced in the liquid phase [Ind. Eng. Chem. Res. 37 (1998) 2707-2712, Energy Fuels 16 (2002) 338-342).

Domestic waste PVC collected is 100,000 tons / year. In addition, over 30,000 tons / year is imported from abroad, and among the recycling technologies of waste resources, PVC processing technology is dominated mainly by material recycling in the domestic market.

Accordingly, in the present invention, in order to efficiently remove hydrochloric acid generated during the treatment of waste PVC, the efficiency of treatment of waste PVC by using a metal oxide or a carbon nitride catalyst under a liquid reaction condition is improved so that an efficient chemical recycling method .

It is an object of the present invention to provide a method for efficiently dechlorinating a waste PVC while mitigating apparatus corrosion by hydrochloric acid.

The first aspect of the present invention relates to a process for producing polyvinyl chloride (PVC) by reacting polyvinyl chloride (PVC) as a reaction solvent in a polyethylene glycol, an ionic liquid or a mixed solvent thereof under a metal oxide or a carbon nitride (C ₃ N ₄ ) (HCl) from polyvinyl chloride (PVC) comprising the first step of obtaining the hydrochloric acid (HCl).

The second aspect of the present invention relates to a process for producing a polyvinyl chloride (PVC) by reacting a waste polyvinyl chloride (PVC) as a reaction solvent in the presence of a metal oxide or a carbon nitride (C ₃ N ₄ ) catalyst in polyethylene glycol, (PVC), comprising the steps of: (1) obtaining a polyvinyl chloride (PVC);

A third aspect of the present invention provides a catalyst for dechlorination reaction of polyvinyl chloride (PVC) characterized by containing carbon nitride (C ₃ N ₄ ).

A fourth aspect of the present invention provides a catalyst characterized in that it contains a support and a hydrochloric acid (HCl) adsorbable metal oxide supported on the support.

Hereinafter, the configuration of the present invention will be described in detail.

In the case of using waste PVC processing and / or recycling method through existing physical recycling technology, oxidation reaction and pyrolysis reaction, hydrochloric acid may be generated during processing and / or recycling of waste PVC, Problems, and the like. In the present invention, polyethylene glycol (PEG), an ionic liquid (IL) or a mixed solvent thereof is used as a reaction solvent in the dehydrochlorination reaction of PVC, and a metal oxide or carbon By performing a dechlorination reaction of PVC under a liquid environment using a nitrile (C ₃ N ₄ ) catalyst, it is possible to alleviate the corrosion problem of the apparatus due to hydrochloric acid, which is a problem in the conventional waste PVC processing and / or recycling method The dechlorination reaction of waste PVC can be performed more efficiently. In addition, the hydrochloric acid produced according to the present invention may be recovered through a separation and purification process, and then reused as a starting material, i.e., a raw material, for the production of a vinyl chloride monomer for conventional PVC synthesis. Through this, it is possible to convert to a useful compound by the dechlorination reaction of waste PVC. The present invention is based on this.

As described above, the process for producing hydrochloric acid (HCl) from polyvinyl chloride (PVC) according to the present invention

And a first step of reacting polyvinyl chloride (PVC) as a reaction solvent with polyethylene glycol, an ionic liquid or a mixed solvent thereof under a metal oxide or carbon nitride (C ₃ N ₄ ) catalyst to obtain hydrochloric acid (HCl) .

Further, the dehydrochlorination treatment method of waste polyvinyl chloride (PVC) according to the present invention

(HCl) by reacting waste polyvinyl chloride (PVC) as a reaction solvent in the presence of a metal oxide or a carbon nitride (C ₃ N ₄ ) catalyst in polyethylene glycol, an ionic liquid or a mixed solvent thereof do.

The dechlorination reaction of PVC is a reaction in which chlorine (Cl) contained in the PVC chain is eliminated as shown in Reaction Scheme 1 below. Due to the dechlorination reaction of such PVC, a polyene containing or not containing some chlorine in the PVC chain is produced together with hydrochloric acid.

[Reaction Scheme 1]

Where a is the number of repeats in the PVC chain before the dechlorination reaction of PVC and b is the number of hydrochloric acid molecules produced due to the dechlorination reaction of PVC.

The first step is a step of dehydrochlorination reaction of polyvinyl chloride (PVC) in a liquid environment under a specific reaction solvent under a metal oxide or carbon nitride (C ₃ N ₄ ) catalyst to produce hydrochloric acid (HCl).

In the present invention, PVC waste can be recycled through chemical conversion technology by using waste polyvinyl chloride (PVC) as polyvinyl chloride (PVC).

The term " polyvinyl chloride (PVC) "used in the present invention may mean thermoplastic plastics represented by the following formula (1). The number average molecular weight of PVC may be varied according to the value of n in the following formula (1), and may be, for example, 45,000 to 64,000, but is not limited thereto. PVC is strong, easy to color, hard or flexible, and does not wear well. However, PVC is vulnerable to heat. PVC is used in artificial leather, vinyl records, packaging materials, pipes, electrical insulation, flooring and so on.

[Chemical Formula 1]

As described above, in the present invention, the dechlorination reaction of PVC is carried out in a liquid environment by using polyethylene glycol or an ionic liquid alone or both as a reaction solvent for the dechlorination reaction of PVC, It is characterized by preventing and reducing environmental pollution.

In the present invention, the dehydrochlorination reaction of PVC is carried out in the presence of a metal oxide or a carbon nitride (C ₃ N ₄ ) catalyst in a specific reaction solvent as described above, so that the dechlorination reaction of PVC is carried out more efficiently, preferably at least 63% It can be carried out with a dechlorination digestibility. Specifically, in the examples of the present invention, the dechlorination reaction of PVC is carried out in a reaction solvent of polyethylene glycol and / or an ionic liquid under a metal oxide or carbon nitride (C ₃ N ₄ ) catalyst to exhibit a dechlorination rate of 63% or more (Examples 1 to 7).

As used herein, the term "dechlorination digestibility" means the ratio of chlorine atoms separated from the total chlorine atoms based on the number of atoms. The dechlorination rate of PVC is determined by the dechlorination reaction among the total chlorine atoms of PVC May refer to the ratio of chlorine atoms.

The term " polyethylene glycol (PEG) "used in the present invention may mean a polyether compound represented by the following formula (2). PEG may vary in number average molecular weight according to the value of m in the following formula (2), and PEG having a wide number average molecular weight of 300 to 10,000,000 may be commercially available.

(2)

_{H- (O-CH 2 -CH 2} ) m -OH

In the present invention, the polyethylene glycol may have a number average molecular weight of 300 to 500. By using polyethylene glycol having a number average molecular weight in the above range as a reaction solvent, it is easy to increase the solubility of PVC and to produce a homogeneous mixture with an ionic liquid, thereby facilitating the removal of HCl produced during the reaction Which is advantageous as a solvent in the dechlorination reaction of PVC.

As used herein, the term "ionic liquid (IL)" may refer to an ionic salt present as a liquid at a temperature of 100 ° C or lower. In particular, an ionic liquid that exists as a liquid at room temperature is referred to as a room temperature ionic liquid (RTIL). Ionic liquids are nonvolatile, non-toxic, non-flammable, have excellent thermal stability and ionic conductivity, and have a unique characteristic that they have high polarity to dissolve inorganic and organic metal compounds and exist as liquids over a wide temperature range. The ionic liquid is composed of an organic cation and an anion. Examples of the cation include dialkylimidazolium, alkylpyridinium, quaternary ammonium, and quaternary phosphonium. The anions include Cl ^- , NO ₃ ^- , BF ₄ ^{- _{PF 6 -, AlCl 4 -,}} Al 2 Cl 7 -, AcO -, TfO - (trifluoromethanesulfonate), Tf 2 N - (trifluoromethanesulfonylamide, (CF 3 SO 2) 2 N)), CH 3 CH (OH) CO 2 - (L-lactate).

Specifically, in the present invention, the ionic liquid is selected from the group consisting of 1-butyl-3-methylimidazolium chloride, [Bmim] Cl, 1-butyl- (1-Butyl-3-methylimidazolium tetrafluoroborate, [Bmim] BF ₄ ) or a mixture thereof.

In the present invention, by using an ionic liquid as a reaction solvent, the cation and anion of the ionic liquid can react with chlorine and hydrogen of the PVC chain, respectively, to further promote the dechlorination reaction of PVC. For example, when [Bmim] Cl is used as the ionic liquid, the dechlorination reaction of PVC can be promoted as shown in the following reaction formula (2).

[Reaction Scheme 2]

As used herein, the term "metal oxide catalyst" may refer to a metal oxide having catalytic activity for the dechlorination reaction of PVC. In the present invention, the metal oxide catalyst may be specifically magnesium oxide (MgO), calcium oxide (CaO), aluminum oxide (Al ₂ O ₃ ), or a mixture thereof.

In the present invention, the metal oxide catalyst accelerates the dechlorination reaction of PVC, and hydrochloric acid (HCl) generated through the dechlorination reaction of PVC is adsorbed thereby causing the hydrochloric acid gas to leak into the line during the reaction process, And also to prevent the occurrence of the problem. That is, in the present invention, the metal oxide catalyst is a catalyst for the dechlorination reaction of PVC and can act as an adsorbent for hydrochloric acid (HCl) gas. For example, when magnesium oxide or calcium oxide is used as the metal oxide catalyst, hydrochloric acid (HCl) can be adsorbed as shown in the following reaction formula (3).

[Reaction Scheme 3]

MO + xHCl - > MO xHCl

Where M is magnesium or calcium and x can be a real number greater than 0 and less than or equal to 2, preferably a real number between 0.1 and 2.

As used herein, the term "carbon nitride" may refer to a carbon nitride having the formula C ₃ N ₄ . Examples of the carbon nitride include alpha-beta, cubic, pseudocubic, or graphitic carbon nitride, and they may be collectively referred to as carbon nitride although the three-dimensional structures are different from each other. The carbon nitride may be a film type, a hollow spherical type, a nanotube type, or the like.

In one embodiment, graphitic carbon nitride may be used as the carbon nitride. The graphite carbon nitride has regularly arranged macro-sized spherical pores. The macro-sized spherical pores are three-dimensionally interconnected with meso-sized connecting pores. At the same time, the nitrogen- The catalytic activity can be increased and the metal oxide can be easily supported.

In the present invention, the carbon nitride catalyst may be a carbon nitride catalyst which is active in the dechlorination reaction of PVC, and may further contain a metal oxide. The metal oxide in the carbonitride catalyst may be magnesium oxide (MgO), calcium oxide (CaO), aluminum oxide (Al ₂ O ₃ ), or a mixture thereof.

In the present invention, the content of the metal in the metal oxide contained in the carbonitride catalyst may be preferably 0 to 15% by weight, based on the weight of the carbon nitride. If the content of the metal in the metal oxide contained in the carbon nitride catalyst is more than 15% by weight, it is difficult to control the appropriate acid sites on the carbon nitride, so that it may be difficult to secure a good conversion ratio in the dechlorination reaction. Specifically, when carbon nitride containing Al ₂ O ₃ as a metal oxide is used as a catalyst, when the catalyst is produced so that the weight of Al is 0 to 15% by weight relative to the weight of the carbon nitride, as the appropriate acid sites keeping Al ₂ O ₃ may be acid sites is secured dechlorination reaction conversion of PVC suggested in the present invention is to create an additional by, the modulation of, if it exceeds the above range, the appropriate acid sites on the carbon nitride It is difficult to secure a good conversion ratio in the dechlorination reaction. Therefore, it is necessary to maintain the above weight ratio (Comparative Example 4).

In the present invention, the reaction temperature of the first step, that is, the dechlorination reaction temperature of PVC may be 150 to 250 ° C. In general, the pyrolysis reaction leading to the dechlorination of PVC is carried out at a high temperature of 400 ° C or higher. However, in the present invention, as described above, since the metal oxide catalyst is a catalyst for the PVC dechlorination reaction and can act as an adsorbent for hydrochloric acid (HCl) gas, hydrochloric acid is removed from the PVC dechlorination reactant and the reaction of the PVC dechlorination reaction is dominant Which can lower the reaction temperature thermodynamically, which makes it possible to dechlorinate PVC at a relatively low temperature of 250 ° C or less, which is advantageous in terms of energy efficiency.

In one embodiment, the method for producing the carbonitrides used in the present invention will be described in more detail as follows.

As a method for producing carbon nitride used as a catalyst and a support, a conventional method used in the related art can be used without limitation, and in one embodiment, a melamine resin powder is used, The temperature was raised at a rate of about 1 to 3 ° C / minute, and then the temperature was maintained at 30 ° C for 30 minutes. Then, the temperature was raised at a rate of about 1 to 3 ° C / minute from 250 ° C to 350 ° C, held at 350 ° C for 30 minutes, After the temperature is raised at a rate of about 3 to 5 ° C / min, the carbon nitride support can be produced by carburization while being maintained for 240 minutes. Through the temperature raising rate and the manufacturing method proposed in the present invention, the melamine resin is able to produce a powdery carbon nitride catalyst through rearrangement of carbon and nitrogen through condensation and thermal-decomposition reaction .

In addition, as one embodiment, a method for producing carbon nitride containing Al ₂ O ₃ will be described in more detail as follows.

First, a precursor is prepared by stirring aluminum isopropoxide (hereinafter referred to as AIP) with melamine resin in 50 ml of isopropyl alcohol (hereinafter referred to as 2-propanol). Then, after aging for about 1 hour, the solvent 2-propanol is removed through reduced-pressure drying and then dried at 80 ° C for 12 hours or more. The temperature was raised from 250 ° C to 350 ° C at a rate of 1 ° C / min for 1 hour and then maintained for 30 minutes at 350 ° C to 550 ° C in a nitrogen atmosphere. And the temperature was maintained at 550 ° C for 4 hours at a rate of 1 ° C / minute from 550 ° C to the final temperature to produce carbon nitride containing powdered Al ₂ O ₃ .

An embodiment of performing a catalytic reaction for efficiently recycling hydrochloric acid from the waste PVC shown in the present invention will be described in more detail as follows.

In a 50 ml three-necked flask, 35 ml of PEG 400, PVC and metal oxide were added at a constant rate, and the stirring rate was raised to 170 ° C at 20 rpm and maintained for 6 hours. Further, an ionic liquid 1-butyl-3-methylimidazonium chloride ([Bmim] Cl) and 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim] BF ₄ ) And the reaction was carried out. As the reaction progresses, the color of the solution can observe the color change of the yellow - brown - dark solution. In the above reaction, the weight ratio of PVC / metal oxide was maintained at 1 / 0.05 to proceed the reaction. After the reaction is completed, unreacted PVC and metal oxides sink downward in a solid form, and the liquid phase portion of the upper layer is separated and titrated with 0.2M sodium hydroxide (NaOH) to determine the conversion of PVC to dechlorination.

The hydrochloric acid (HCl) produced by the process according to the present invention can be used as a raw material for the production of a vinyl chloride monomer as described above. Hydrochloric acid (HCl) produced by the process according to the present invention may be recovered in a hydrochloric acid gas state in a small amount and in a dissolved state in the reaction solvent. Accordingly, before reusing hydrochloric acid as a chemical raw material, the hydrochloric acid dissolved in the reaction solvent can be recovered in a gaseous state using a stripping process.

As described above, the present invention can provide a catalyst for dechlorination reaction of polyvinyl chloride (PVC) characterized by containing carbon nitride (C ₃ N ₄ ).

Further, the present invention can provide a catalyst characterized by containing a support and a metal oxide capable of adsorbing hydrochloric acid (HCl) supported on the support as described above. The metal oxide in the catalyst can adsorb hydrochloric acid (HCl) generated during the reaction and separate hydrochloric acid (HCl) through the metal oxide supported on the support by solid-liquid separation. Preferably, a porous support is used to support a metal oxide in the pores so that a large amount of hydrochloric acid (HCl) can be accommodated in the pores through the metal oxide.

The present invention contributes to the completion of the circulation ecosystem of the waste plastics through the recycling of the waste PVC resources causing the environmental problems through the chemical recycling technology of the waste PVC. In addition, it is possible to reduce environmental pollution due to recycling of waste resources and create new added value, and it is possible to reduce the throughput by landfill by applying it to the production of various products using waste PVC, and it is possible to reduce a large amount of greenhouse gas reduction It is expected. In addition, it is expected that new value added will be created through the development of materials recycling technology and chemical recycling technology of waste PVC scrap.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the following examples are intended to illustrate the present invention, and thus the scope of application of the present invention is not limited to these examples.

Example  One

The dechlorination reaction of PVC in liquid phase was carried out by the following method. The material used for the reaction was 1 g of PVC. The reaction solvent used was 35 ml of PEG 400 and 1-Butyl-3-methylimidazolium Chloride (hereinafter referred to as [Bmim] Cl) 0.5 g. As the catalyst, 0.05 g of magnesium oxide (MgO) was used. The reaction mixture, the reaction solvent and the catalyst were placed in a 50 ml three-necked flask, and the mixture was heated to 170 ° C while stirring, and the reaction was continued for 6 hours. After the reaction was completed, the temperature was lowered to room temperature, and the liquid phase portion of the upper layer excluding the solid region in which the PVC and the catalyst had settled was separated and titrated with 0.2 M sodium hydroxide (NaOH) to determine the conversion rate %) Was measured. The solvent and the catalyst used at this time are represented by PEG400 + [Bmim] Cl (MgO), and the dechlorination rate is shown in Table 1 below.

Example  2

Except that 1-butyl-3-methylimidazolium tetrafluoroborate, [Bmim] BF ₄ ) was used instead of [Bmim] Cl as an ionic liquid in the reaction solvent. The dechlorination reaction of PVC was carried out in the same manner as in Example 1. The solvent and the catalyst used at this time are represented by PEG 400 + [Bmim] BF ₄ (MgO), and the dechlorination rate is shown in Table 1 below.

Example  3

Dechlorination reaction of PVC was carried out in the same manner as in Example 1 except that 0.05 g of calcium oxide (CaO) was used instead of magnesium oxide as a catalyst. The solvent and the catalyst used at this time are represented by PEG400 + [Bmim] Cl (CaO) and the dechlorination rate is shown in Table 1 below.

Example  4

Except that 1-butyl-3-methylimidazolium tetrafluoroborate, [Bmim] BF ₄ ) was used instead of [Bmim] Cl as an ionic liquid in the reaction solvent. The dechlorination reaction of PVC was carried out in the same manner as in Example 3. The solvent and the catalyst used at this time are represented by PEG400 + [Bmim] BF ₄ (CaO) and the dechlorination rate is shown in Table 1 below.

Example  5

The dechlorination reaction of PVC was carried out in the same manner as in Example 1 except that only PEG 400 was used as the reaction solvent and only carbon nitride not containing Al ₂ O ₃ was used as the catalyst.

The carbon nitride catalyst to be used at this time was prepared as follows.

First, the melamine resin powder was heated to 250 ° C at a rate of about 2 ° C / minute for 30 minutes under a nitrogen atmosphere, heated from 250 ° C to 350 ° C at a rate of about 2 ° C / minute, C for 30 minutes, then heated from 350 ° C to 550 ° C at a rate of about 4 ° C / minute, and then held for 240 minutes to prepare a carbon nitride catalyst using carburization.

The solvent and the catalyst used at this time are represented by PEG ₄₀₀ (Al (O) -C ₃ N ₄ ) and the dechlorination rate is shown in Table 1 below.

Example  6

The dehydrochlorination reaction of PVC was carried out in the same manner as in Example 5 except that Al was a carbon nitride catalyst containing Al ₂ O ₃ in an amount of 5 wt% based on the weight of carbon nitride.

The carbon nitride catalyst to be used at this time was prepared as follows.

First, 1.894 g of aluminum isopropoxide (hereinafter referred to as AIP) was stirred in 50 ml of isopropyl alcohol (hereinafter referred to as 2-propanol) together with 4.75 g of melamine resin. Thereafter, after aging for about 1 hour, the solvent 2-propanol was removed by drying under reduced pressure and then dried at 80 ° C for 12 hours or more. After being heated for 2 hours at a rate of 1 占 폚 / min in a nitrogen atmosphere, the temperature was maintained for 30 minutes, and the temperature was increased from 250 占 폚 to 350 占 폚 at a rate of 1 占 폚 / min for 1 hour and then maintained for 30 minutes at 350 占 폚 to 550 占 폚 / min rate was 1 timekeeping after 4 hours the temperature was raised to, and lowered the temperature for 4 hours at a rate of 1 ℃ / min to room temperature in 550 ℃, was prepared in a final Al ₂ O ₃ is contained carbon nitride.

The solvent and the catalyst used at this time are represented by PEG ₄₀₀ (Al (5) -C ₃ N ₄ ) and the dechlorination rate is shown in Table 1 below.

Example  7

The dehydrochlorination reaction of PVC was carried out in the same manner as in Example 5, except that Al was a carbon nitride catalyst containing Al ₂ O ₃ in an amount of 10% by weight based on the weight of carbon nitride.

The carbon nitride catalyst to be used at this time was prepared as follows.

First, 3.789 g of aluminum isopropoxide (hereinafter referred to as AIP) was stirred with 4.5 g of melamine resin in 50 ml of isopropyl alcohol (hereinafter referred to as 2-propanol). Thereafter, after aging for about 1 hour, the solvent 2-propanol was removed by drying under reduced pressure and then dried at 80 ° C for 12 hours or more. After being heated for 2 hours at a rate of 1 占 폚 / min in a nitrogen atmosphere, the temperature was maintained for 30 minutes, and the temperature was increased from 250 占 폚 to 350 占 폚 at a rate of 1 占 폚 / min for 1 hour and then maintained for 30 minutes at 350 占 폚 to 550 占 폚 / min rate was 1 timekeeping after 4 hours the temperature was raised to, and lowered the temperature for 4 hours at a rate of 1 ℃ / min to room temperature in 550 ℃, was prepared in a final Al ₂ O ₃ is contained carbon nitride.

The solvent and the catalyst used at this time were represented by PEG ₄₀₀ (Al (10) -C ₃ N ₄ ), and the dechlorination rate is shown in Table 1 below.

Comparative Example  One

Dechlorination reaction of PVC was carried out in the same manner as in Example 1 except that PEG 400 alone was used as a reaction solvent and dechlorination reaction of PVC was carried out in the absence of a catalyst.

The solvent and the catalyst used in this step are represented by PEG 400 (w / o cat) and the dechlorination rate is shown in Table 1 below.

Comparative Example  2

The dechlorination reaction of PVC was carried out in the same manner as in Example 1 except that the dechlorination reaction of PVC was carried out in the absence of a catalyst.

The solvent and the catalyst used at this time are represented by PEG400 + [Bmim] Cl (w / o cat), and dechlorination rate is shown in Table 1 below.

Comparative Example  3

The dehydrochlorination reaction of PVC was carried out in the same manner as in Example 2 except that the dechlorination reaction of PVC was carried out in the absence of a catalyst.

Solvent and the catalyst used in this case is PEG400 + [Bmim] BF ₄ (w / o cat), and the dechlorination rate is shown in Table 1 below.

Comparative Example  4

The dechlorination reaction of PVC was carried out in the same manner as in Example 5, except that Al was a carbon nitride catalyst containing Al ₂ O ₃ in an amount of 20 wt% based on the weight of carbon nitride.

The carbon nitride catalyst to be used at this time was prepared as follows.

First, 7.578 g of aluminum isopropoxide (hereinafter referred to as AIP) was stirred with 4.00 g of melamine resin in 50 ml of isopropyl alcohol (hereinafter referred to as 2-propanol). Thereafter, after aging for about 1 hour, the solvent 2-propanol was removed by drying under reduced pressure and then dried at 80 ° C for 12 hours or more. After being heated for 2 hours at a rate of 1 占 폚 / min in a nitrogen atmosphere, the temperature was maintained for 30 minutes, and the temperature was increased from 250 占 폚 to 350 占 폚 at a rate of 1 占 폚 / min for 1 hour and then maintained for 30 minutes at 350 占 폚 to 550 占 폚 / min rate was 1 timekeeping after 4 hours the temperature was raised to, and lowered the temperature for 4 hours at a rate of 1 ℃ / min to room temperature in 550 ℃, was prepared in a final Al ₂ O ₃ is contained carbon nitride.

The solvent and the catalyst used at this time are represented by PEG ₄₀₀ (Al (20) -C ₃ N ₄ ) and the dechlorination rate is shown in Table 1 below.

division The solvent (catalyst) Dechlorination digestibility (%) Example 1 PEG400 + [Bmim] Cl (MgO) 88 Example 2 _{PEG400 + [Bmim] BF 4 (} MgO) 75 Example 3 PEG400 + [Bmim] Cl (CaO) 88 Comparative Example 4 _{PEG400 + [Bmim] BF 4 (} CaO) 63 Example 5 _{PEG400 (Al (0) -C 3} N 4) 63 Example 6 _{PEG400 (Al (5) -C 3} N 4) 63 Example 7 _{PEG400 (Al (10) -C 3} N 4) 75 Comparative Example 1 PEG400 (w / o cat) 51 Comparative Example 2 PEG400 + [Bmim] Cl (w / o cat) 60 Comparative Example 3 PEG400 + [Bmim] BF ₄ (w / o cat) 56 Comparative Example 4 _{PEG400 (Al (20) -C 3} N 4) 50

The results are shown in Table 1. As shown in Table 1, the dehydrochlorination reactivity of PVC was excellent when MgO and CaO as catalysts (Examples 1 to 4) were used in addition to the reaction solvent of the present invention, and PEG (Comparative Example 1), and when the PEG and the ionic liquid were used as the reaction solvent and the catalyst was not used (Comparative Examples 2 and 3), the dechlorination rate was decreased. As a catalyst system for treating waste PVC, in the case of carbon nitride containing Al ₂ O ₃ , when the catalyst is manufactured so that the weight of Al is 0 to 15 wt% relative to the weight of carbon nitride It was confirmed that the dechlorination digestibility was excellent in Example 5 to 7 but the dechlorination rate was decreased in the case of using carbon nitride having an Al content exceeding 20% by weight (Comparative Example 4). According to the above results, when the metal oxide and Al ₂ O ₃ -containing carbon nitride are used, the dechlorination conversion rate can be increased to 63% or more under the reaction solvent conditions of the present invention Able to know.

Claims (14)

(HCl) by reacting polyvinyl chloride (PVC) as a reaction solvent in the presence of a metal oxide or a carbon nitride (C ₃ N ₄ ) catalyst in polyethylene glycol, an ionic liquid or a mixed solvent thereof, A process for producing hydrochloric acid (HCl) from polyvinyl chloride (PVC).
The method according to claim 1, wherein waste polyvinyl chloride (PVC) is used as the polyvinyl chloride (PVC).
The method according to claim 1, wherein the polyethylene glycol has a number average molecular weight of 300 to 500.
2. The method of claim 1, wherein the ionic liquid is selected from the group consisting of 1-butyl-3-methylimidazolium chloride, [Bmim] Cl, 1-butyl- (1-Butyl-3-methylimidazolium tetrafluoroborate, [Bmim] BF ₄ ) or a mixture thereof.
The method of claim 1, wherein the metal oxide catalyst is magnesium oxide (MgO), calcium oxide (CaO), aluminum oxide (Al ₂ O ₃ ), or a mixture thereof.
The method of claim 1, wherein the carbon nitride catalyst further comprises a metal oxide.
The method of claim 6, wherein the metal oxide in the carbonitride catalyst is magnesium oxide (MgO), calcium oxide (CaO), aluminum oxide (Al ₂ O ₃ ) / RTI >
The method of claim 6, wherein the content of metal in the metal oxide contained in the carbonitride catalyst is 0 to 15 wt%, based on the weight of the carbon nitride.
The method of claim 1, wherein the reaction temperature in the first step is 150 to 250 ° C.
The method according to claim 1, wherein the hydrochloric acid (HCl) produced by the method is used as a raw material for the production of a vinyl chloride monomer.
(HCl) by reacting waste polyvinyl chloride (PVC) as a reaction solvent in the presence of a metal oxide or a carbon nitride (C ₃ N ₄ ) catalyst in polyethylene glycol, an ionic liquid or a mixed solvent thereof Dechlorination treatment of waste polyvinyl chloride (PVC).
A catalyst for dechlorination reaction of polyvinyl chloride (PVC), characterized in that it contains carbon nitride (C ₃ N ₄ ).
13. The catalyst of claim 12, wherein the carbonitride catalyst further comprises a metal oxide.
A support, and a hydrochloric acid (HCl) adsorbable metal oxide supported on the support.