Efficient formaldehyde removal agent and preparation method thereof

Abstract

The invention discloses an efficient formaldehyde removal agent and a preparation method thereof. The formaldehyde removal agent comprises the following preparation raw materials in percentage by mass: 20-35% of carboxyl-terminated hyperbranched polyester; 2-6% of an amination reagent; 20 to 30 percent of melamine; 1-4% of ethylene glycol; 1-5% of a polymer carrier; 1-3% of methyl cellulose; 5-15% of a surfactant; and 20-30% of a weak alkaline solution. By introducing an amination reagent and melamine, melamine and amino functional groups in terminal-modified carboxyl hyperbranched polyester are connected to a polyester chain through chemical bonds to form a stable network structure, the stability of the formaldehyde removal agent is guaranteed, mutual catalysis is achieved, multiple reaction paths are formed, the formaldehyde removal rate is increased, and the formaldehyde removal efficiency is improved. According to the invention, formaldehyde molecules are more easily subjected to protonation in combination with an alkalescent environment, an ion form easy to react is formed, an efficient formaldehyde removal effect is realized, and the formaldehyde adsorbent has excellent performances of stable performance, multiple reaction paths and environmental protection and safety, thereby having a good application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of formaldehyde removal, and particularly to the use of gas-liquid contact, specifically to a high-efficiency formaldehyde removal agent and its preparation method. Background Art

[0002] Formaldehyde, as a common indoor air pollutant, the harm it poses to human health cannot be ignored. Formaldehyde mainly comes from decoration materials, furniture, coatings, and some chemical products in daily life, such as cleaners, preservatives, etc. Long-term exposure to a formaldehyde environment will pose serious threats to human health in many aspects.

[0003] Formaldehyde is highly irritating and can irritate the eyes, nose, and throat, causing symptoms such as tearing, nasal congestion, and coughing. For people with allergic constitutions, formaldehyde may also trigger respiratory diseases such as allergic rhinitis and asthma. Formaldehyde is listed as one of the carcinogenic substances by the World Health Organization (WHO). Long-term inhalation of formaldehyde, especially at high concentrations, will increase the risk of developing malignant tumors such as nasopharyngeal cancer and leukemia. After entering the human body through the respiratory tract, formaldehyde can affect the normal metabolism and proliferation of cells, thereby inducing gene mutations and cell carcinogenesis. It also damages the human nervous system and immune system. Long-term exposure to formaldehyde may lead to neurological symptoms such as memory loss and inattention, as well as immune system problems such as a decline in immunity and susceptibility to colds. For pregnant women and children, the harm of formaldehyde is even more serious, and it may cause fetal malformations, slow growth and development of children, etc.

[0004] Traditional formaldehyde removal methods include physical adsorption (such as activated carbon, zeolite), chemical neutralization (such as urea, ammonium chloride), plant extracts, etc., but these methods generally have problems such as low formaldehyde removal efficiency, easy saturation, short validity period, or possible secondary pollution.

[0005] Therefore, there is an urgent need for a high-efficiency formaldehyde removal agent that can quickly and effectively remove indoor formaldehyde. Summary of the Invention

[0006] The present invention overcomes the deficiencies of the prior art and provides a high-efficiency formaldehyde removal agent and its preparation method.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a high-efficiency formaldehyde removal agent, and the formaldehyde removal agent includes the following preparation raw materials in mass percentage:

[0008]

[0009] In a preferred embodiment of the present invention, the terminal carboxyl hyperbranched polyester is one of HyPer C202, HyPer C203, HyPer C302, or HyPer C303.

[0010] In a preferred embodiment of the present invention, the amination reagent is one of ethylenediamine or diethylenetriamine.

[0011] In a preferred embodiment of the present invention, the polymer carrier is one of sodium alginate or carboxymethyl chitosan.

[0012] In a preferred embodiment of the present invention, the tapped density of the methylcellulose is 1.2 - 1.5 g / cm 3 , and the molecular weight is 10,000 - 200,000 Da.

[0013] In a preferred embodiment of the present invention, the surfactant is one of alkylphenol polyoxyethylene ether, fatty acid polyoxyethylene ester, polyoxyethylene alkylamine or polyoxyethylene alkylamide.

[0014] In a preferred embodiment of the present invention, the weak alkaline solution is sodium bicarbonate solution, and the pH value of the sodium bicarbonate solution is 7.5 - 9.

[0015] The present invention provides a preparation method of an efficient formaldehyde removing agent, comprising the following steps:

[0016] S1. Weigh the carboxyl - terminated hyperbranched polyester and the amination reagent in proportion. Dissolve the carboxyl - terminated hyperbranched polyester in dimethyl sulfoxide. During stirring, slowly drop the amination reagent into the carboxyl - terminated hyperbranched polyester solution. At room temperature, stir and react for 30 - 50 min, remove the solvent and dry to obtain the modified carboxyl - terminated hyperbranched polyester.

[0017] S2. Weigh melamine, ethylene glycol, the polymer carrier, methylcellulose, the surfactant and the weak alkaline solution in proportion, and mix and stir them with the modified carboxyl - terminated hyperbranched polyester to obtain the efficient formaldehyde removing agent.

[0018] In a preferred embodiment of the present invention, in the step of S1, the mass ratio of the carboxyl - terminated hyperbranched polyester to the dimethyl sulfoxide is 1:2 - 4, and the drying specifically is: drying at a temperature of 40 - 60 °C for 1 - 2 h.

[0019] In a preferred embodiment of the present invention, in the step of S2, the mixing and stirring rate is 20 - 40 rpm, and the time is 5 - 10 min.

[0020] The present invention solves the defects in the background technology and has the following beneficial effects:

[0021] (1) The present invention provides an efficient formaldehyde-removing agent and a preparation method thereof. By introducing an amination reagent and melamine, the melamine and amino functional groups in the end-modified carboxyl hyperbranched polyester are connected to the polyester chain through chemical bonds, forming a stable network structure, ensuring the stability of the formaldehyde-removing agent, and catalyzing each other to form multiple reaction paths, further accelerating the formaldehyde removal rate. Combined with a weakly alkaline environment, formaldehyde molecules are more likely to be protonated to form an ionic form that is easy to react, achieving an efficient formaldehyde removal effect, and having excellent properties such as stable performance, multiple reaction paths, environmental protection and safety, thus having good application prospects.

[0022] (2) In the present invention, by introducing amino and imino groups at the end of the carboxyl-terminated hyperbranched polyester, additional amino functional groups are added. The lone pair electrons of the nitrogen atoms in the amino and imino groups can undergo an addition reaction or a condensation reaction with the carbon-oxygen double bond in the formaldehyde molecule to form new chemical bonds, which not only increases the contact area and reaction sites between the polyester molecule and the formaldehyde molecule, but also improves the overall reaction activity, thereby better enhancing the adsorption and catalytic ability for formaldehyde.

[0023] (3) In the present invention, through the introduction of melamine, the nitrogen atom therein acts as a nucleophile and can attack the carbon-oxygen double bond of the formaldehyde molecule to undergo a nucleophilic addition reaction to form a stable compound, and can form hydrogen bonds or coordination bonds with the hydrogen atom or oxygen atom in the formaldehyde molecule to further stabilize the reaction product. At the same time, under the combined action with the modified carboxyl-terminated hyperbranched polyester, the formaldehyde-removing agent is significantly improved in terms of the number of active groups, reaction rate, stability and persistence.

[0024] (4) In the present invention, through the combination with a sodium bicarbonate solution, due to the hydrogen bond interaction between the sodium bicarbonate molecule and the water molecule in the sodium bicarbonate solution, when the formaldehyde molecule enters the solution, the carbon-oxygen double bond in its aldehyde group will be attacked by the hydroxide ion, causing it to undergo an addition or condensation reaction. And the weakly alkaline environment accelerates the protonation process of formaldehyde to form methylene glycol ions or formyl ions. These ionic forms of formaldehyde are more likely to react with the active groups in the modified polyester and melamine, promoting the reaction rate and helping to effectively remove a large amount of formaldehyde in a short time, thereby further improving the formaldehyde-removing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings;

[0026] Figure 1 It is a schematic flow chart of a preparation method of an efficient formaldehyde removing agent according to a preferred embodiment of the present invention. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0029] It should be noted that the raw materials, equipment, reagents, etc. used in the present invention can all be obtained through market purchase or by means of preparation in the prior art.

[0030] An efficient formaldehyde removing agent, and the formaldehyde removing agent includes the following preparation raw materials in mass percentages:

[0031]

[0032] In some specific implementation manners, the end-carboxyl hyperbranched polyester is one of HyPer C202, HyPer C203, HyPerC302 or HyPer C303.

[0033] In some specific implementation manners, the amination reagent is one of ethylenediamine or diethylenetriamine.

[0034] In some specific implementation manners, the polymer carrier is one of sodium alginate or carboxymethyl chitosan.

[0035] In some specific implementation manners, the tapped density of methylcellulose is 1.2 - 1.5 g / cm 3 , and the molecular weight is 10,000 - 200,000 Da.

[0036] In some specific implementation manners, the surfactant is one of alkylphenol polyoxyethylene ether, fatty acid polyoxyethylene ester, polyoxyethylene alkylamine or polyoxyethylene alkylamide.

[0037] In some specific implementation manners, the weak alkaline solution is a sodium bicarbonate solution, and the pH value of the sodium bicarbonate solution is 7.5 - 9.

[0038] Such as Figure 1As shown in the figure, the present invention provides a preparation method of an efficient formaldehyde removal agent, comprising the following steps:

[0039] S1. Weigh the terminal carboxyl hyperbranched polyester and the amination reagent in proportion. Dissolve the terminal carboxyl hyperbranched polyester in dimethyl sulfoxide. During stirring, slowly drop the amination reagent into the terminal carboxyl hyperbranched polyester solution. At room temperature, stir and react for 30 - 50 min, remove the solvent and dry to obtain the modified terminal carboxyl hyperbranched polyester.

[0040] S2. Weigh melamine, ethylene glycol, polymer carrier, methyl cellulose, surfactant and weak alkaline solution in proportion, and mix and stir them with the modified terminal carboxyl hyperbranched polyester to obtain the efficient formaldehyde removal agent.

[0041] In some specific embodiments, in the step of S1, the mass ratio of the terminal carboxyl hyperbranched polyester to dimethyl sulfoxide is 1:2 - 4. The drying specifically is: at a temperature of 40 - 60 °C, dry for 1 - 2 h.

[0042] In some specific embodiments, in the step of S2, the mixing and stirring rate is 20 - 40 rpm, and the time is 5 - 10 min.

[0043] The following is a detailed description of the general implementation scheme of the present invention in combination with specific embodiments.

[0044] The preparation raw material ratios of Examples 1 - 6 are different, as specifically shown in Table 1, and the raw material consumption is measured by mass percentage.

[0045] Table 1:

[0046]

[0047]

[0048] Example 1

[0049] A preparation method of an efficient formaldehyde removal agent, comprising the following steps:

[0050] S1. Weigh HyPer C203 and ethylenediamine in proportion. Dissolve HyPer C203 in dimethyl sulfoxide. The mass ratio of HyPer C203 to dimethyl sulfoxide is 1:4. During stirring, slowly drop ethylenediamine into the HyPer C203 solution. At room temperature, stir and react for 30 min, remove the solvent, and at a temperature of 50 °C, dry for 1.5 h to obtain the modified HyPerC203.

[0051] S2. Weigh melamine, ethylene glycol, carboxymethyl chitosan, methyl cellulose, alkylphenol polyoxyethylene ether and sodium bicarbonate solution in proportion, and mix and stir them with modified HyPer C203 at a rate of 30 rpm for 5 minutes to obtain a high-efficiency formaldehyde removal agent.

[0052] Example 2

[0053] This example is basically the same as Example 1, except that: the raw materials and their ratios are different, as shown in Table 1.

[0054] Example 3

[0055] This example is basically the same as Example 1, except that: the raw materials and their ratios are different, as shown in Table 1; the steps of S1 are specifically as follows: Weigh HyPer C203 and ethylenediamine in proportion, dissolve HyPer C203 in dimethyl sulfoxide, and the mass ratio of HyPer C203 to dimethyl sulfoxide is 1:3. During the stirring process, slowly drop ethylenediamine into the HyPer C203 solution, and stir and react at room temperature for 30 minutes. Remove the solvent, and dry at a temperature of 50°C for 1.5 hours to obtain modified HyPer C203.

[0056] Example 4

[0057] This example is basically the same as Example 1, except that: the raw materials and their ratios are different, as shown in Table 1.

[0058] Example 5

[0059] This example is basically the same as Example 1, except that: the raw materials and their ratios are different, as shown in Table 1; the steps of S1 are specifically as follows: Weigh HyPer C203 and diethylenetriamine in proportion, dissolve HyPer C203 in dimethyl sulfoxide, and the mass ratio of HyPer C203 to dimethyl sulfoxide is 1:2. During the stirring process, slowly drop diethylenetriamine into the HyPer C203 solution, and stir and react at room temperature for 30 minutes. Remove the solvent, and dry at a temperature of 50°C for 1.5 hours to obtain modified HyPer C203.

[0060] Example 6

[0061] This example is basically the same as Example 1, except that: the raw materials and their ratios are different, as shown in Table 1.

[0062] Performance detection: The formaldehyde scavengers obtained from the above Examples 1-6 were respectively placed in aerosol cans, and 20% of the total content of the propellant was pressed into the formaldehyde scavengers by a pressing machine using the pressure filling method. Six boards of the same size and specification were respectively placed in six closed boxes of the same size and specification. A toxic and harmful gas detector with the model X-am5100 was used to detect the formaldehyde content in the six closed boxes. The average value of the formaldehyde content was between 850-920 ppm. The formaldehyde scavengers prepared in Examples 1-6 were respectively sprayed with 50 g on the boards in the six closed boxes. After 10 min, 20 min, 30 min, and 50 min, a toxic and harmful gas detector with the model X-am5100 was used for detection. The performance test results are shown in Table 2.

[0063] Table 2:

[0064]

[0065] It can be seen from Table 2 that:

[0066] By comparing the formaldehyde values (ppm) of the formaldehyde scavengers prepared in Examples 1-6 for the formaldehyde removal effect, it can be known that by introducing an amination reagent and melamine in the present invention, the melamine and amino functional groups in the end-modified carboxyl hyperbranched polyester are connected to the polyester chain through chemical bonds, forming a stable network structure, ensuring the stability of the formaldehyde scavenger, and catalyzing each other to form multiple reaction paths, further accelerating the formaldehyde removal rate. Combining with a weakly alkaline environment, the formaldehyde molecules are more likely to be protonated to form an ionic form that is easy to react, achieving an efficient formaldehyde removal effect, and having excellent properties of stable performance, multiple reaction paths, and environmental protection and safety, thus having good application prospects.

[0067] To further make the purpose and effect of the present invention simple and easy to understand, the present invention is further elaborated in combination with specific comparative examples.

[0068] Comparative Example 1

[0069] This comparative example is basically the same as Example 1, and the difference lies in: the raw material ratio is different, there is no ethylenediamine, and the content of HyPerC203 is 34 wt%; there is no S1 step, and the S2 step is: weighing melamine, ethylene glycol, carboxymethyl chitosan, methyl cellulose, alkylphenol polyoxyethylene ether, and sodium bicarbonate solution in proportion, and mixing and stirring with HyPer C203 at a rate of 30 rpm for 5 min to obtain a high-efficiency formaldehyde scavenger.

[0070] Comparative Example 2

[0071] This comparative example is basically the same as Example 1, and the difference lies in: the raw material ratio is different, the content of ethylenediamine is 1 wt%, and the content of HyPer C203 is 33 wt%.

[0072] Comparative Example 3

[0073] This comparative example is basically the same as Example 1, except that: the raw material ratio is different, the content of ethylenediamine is 8 wt%, and the content of HyPer C203 is 26 wt%.

[0074] Comparative Example 4

[0075] This comparative example is basically the same as Example 1, except that: the raw material ratio is different, the content of melamine is 33 wt%, and the content of HyPer C203 is 22 wt%.

[0076] Comparative Example 5

[0077] This comparative example is basically the same as Example 1, except that: the raw material ratio is different, the sodium bicarbonate solution is replaced with neutral water; Step S2 is: weighing melamine, ethylene glycol, carboxymethyl chitosan, methyl cellulose, alkylphenol polyoxyethylene ether and water in proportion, and mixing and stirring with modified HyPer C203 at a rate of 30 rpm for 5 min to obtain a high-efficiency formaldehyde-removing agent.

[0078] The formaldehyde-removing agents prepared in Comparative Examples 1-5 were tested using the same performance detection method as the formaldehyde-removing agents prepared in Examples 1-6, and the performance test results are shown in Table 3.

[0079] Table 3:

[0080]

[0081]

[0082] It can be seen from Table 3 that:

[0083] Through the comparison between Example 1 and Comparative Example 1, it can be known that by introducing amino groups (—NH2) and imino groups (—NH—) at the ends of the carboxyl-terminated hyperbranched polyester, additional amino functional groups are added. Using the lone pair electrons of the nitrogen atoms in the amino and imino groups, an addition reaction or condensation reaction can occur with the carbon-oxygen double bond in the formaldehyde molecule to form new chemical bonds, which not only increases the contact area and reaction sites between the polyester molecule and the formaldehyde molecule, but also improves the overall reaction activity, thus better enhancing the adsorption and catalytic ability of formaldehyde.

[0084] It can be known from the comparison between Example 1 and Comparative Example 2 and Comparative Example 3 that when the content of the amination reagent is moderate, an appropriate amount of amino and imino active groups can be introduced onto the terminal carboxyl hyperbranched polyester molecules. Effective chemical bonding can occur between these groups and formaldehyde molecules, thereby improving the adsorption performance. However, when the content of the amination reagent is too low, the number of active groups is insufficient, resulting in a reduction in the contact area and reaction sites between the formaldehyde remover and formaldehyde molecules. When the content of the amination reagent is too high, although more amino and imino active groups will be introduced, it is easy to cause the active groups to be too dense, resulting in a steric hindrance effect between molecules, thereby reducing the formaldehyde removal effect.

[0085] It can be known from the comparison between Example 1 and Comparative Example 4 that through the introduction of melamine, the nitrogen atoms therein can act as nucleophiles to attack the carbon-oxygen double bond of formaldehyde molecules, undergoing a nucleophilic addition reaction to form stable compounds, and can form hydrogen bonds or coordination bonds with the hydrogen or oxygen atoms in formaldehyde molecules to further stabilize the reaction products. At the same time, under the combined action with the modified terminal carboxyl hyperbranched polyester, the formaldehyde remover is significantly improved in terms of the number of active groups, reaction rate, stability, and persistence. However, when the content of melamine is too high, in the formaldehyde removal reaction, formaldehyde molecules need to react with the active groups (such as amino, imino, etc.) in the formaldehyde remover. A large number of melamine molecules will occupy the space in the reaction system, resulting in a reduction in the contact opportunities between formaldehyde molecules and other active groups in the formaldehyde remover. Moreover, there will be a competitive relationship between high-concentration melamine molecules, competing for limited reaction sites, which changes the equilibrium state of the formaldehyde removal reaction, thereby reducing the formaldehyde removal effect.

[0086] It can be known from the comparison between Example 1 and Comparative Example 5 that through the combination with sodium bicarbonate solution, using the hydrogen bond interaction between sodium bicarbonate molecules and water molecules in the sodium bicarbonate solution, when formaldehyde molecules enter the solution, the carbon-oxygen double bond in its aldehyde group will be attacked by hydroxide ions, causing addition or condensation reactions. And the weakly alkaline environment accelerates the protonation process of formaldehyde, forming methylene glycol ions or formyl ions. These ionic forms of formaldehyde are more likely to react with the active groups in the modified polyester and melamine, promoting the reaction rate and helping to effectively remove a large amount of formaldehyde in a short time, thereby further improving the formaldehyde removal performance. When only combined with neutral water, although formaldehyde can dissolve in water, the dissolution amount of water is relatively limited, and the volatilization rate of formaldehyde is usually much faster than the rate at which water adsorbs formaldehyde. It does not have direct chemical reactivity to affect the conversion of formaldehyde, reducing the synergistic effect with the modified polyester and melamine, thereby making the formaldehyde removal effect poor.

[0087] Based on the inspiration of the ideal embodiments of the present invention, through the above description, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be encompassed within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0088] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An efficient formaldehyde remover, characterized in that, The formaldehyde-removing agent comprises the following raw materials for preparation in mass percentage:

2. The high-efficiency formaldehyde removing agent according to claim 1, characterized in that: The carboxyl-terminated hyperbranched polyester is one of HyPer C202, HyPer C203, HyPer C302 or HyPer C303.

3. An efficient formaldehyde removing agent according to claim 1, characterized in that: The amination reagent is one of ethylenediamine or diethylenetriamine.

4. An efficient formaldehyde remover according to claim 1, characterized in that: The polymer carrier is one of sodium alginate or carboxymethyl chitosan.

5. An efficient formaldehyde removing agent according to claim 1, characterized in that: The tapped density of the methylcellulose is 1.2 to 1.5 g / cm 3 , and the molecular weight is 10,000 to 200,000 Da.

6. The high-efficiency formaldehyde removing agent according to claim 1, wherein: The surfactant is one of alkylphenol polyoxyethylene ether, fatty acid polyoxyethylene ester, polyoxyethylene alkylamine or polyoxyethylene alkylamide.

7. An efficient formaldehyde remover according to claim 1, characterized in that: The weak alkaline solution is a sodium bicarbonate solution, and the pH value of the sodium bicarbonate solution is 7.5 - 9.

8. A preparation method of an efficient formaldehyde removing agent according to any one of claims 1-7, characterized in that, It includes the following steps: S1. Weigh the carboxyl-terminated hyperbranched polyester and the amination reagent in proportion. Dissolve the carboxyl-terminated hyperbranched polyester in dimethyl sulfoxide. During stirring, slowly add the amination reagent dropwise to the carboxyl-terminated hyperbranched polyester solution. At room temperature, stir and react for 30 - 50 min, remove the solvent and dry to obtain the modified carboxyl-terminated hyperbranched polyester. S2. Weigh melamine, ethylene glycol, the polymer carrier, methyl cellulose, the surfactant and the weak alkaline solution in proportion, and mix and stir them with the modified carboxyl-terminated hyperbranched polyester to obtain the high-efficiency formaldehyde-removing agent.

9. The preparation method of an efficient formaldehyde removing agent according to claim 8, characterized in that: In the step of S1, the mass ratio of the carboxyl-terminated hyperbranched polyester to the dimethyl sulfoxide is 1:2 - 4, and the drying specifically is: drying at a temperature of 40 - 60 °C for 1 - 2 h.

10. The preparation method of an efficient formaldehyde-removing agent according to claim 8, characterized in that: In the step of S2, the mixing and stirring rate is 20 - 40 rpm, and the time is 5 - 10 min.

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