Mixed fatty alcohol polyoxyethylene ether phosphate as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of anionic surfactant synthesis, and discloses mixed fatty alcohol polyoxyethylene ether phosphate as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing at least two different fatty alcohol-polyoxyethylene ether and phosphorus pentoxide, carrying out phosphorylation reaction, and carrying out hydrolysis after the reaction is finished, so as to obtain mixed fatty alcohol-polyoxyethylene ether phosphate; and the atomic number of a fatty chain of the fatty alcohol-polyoxyethylene ether is 8-18. The prepared mixed fatty alcohol polyoxyethylene ether phosphate has high selectivity, high adsorbability and high hard water resistance, can improve the deinking effect of a neutral deinking agent, is wide in application range, and can also be applied to alkaline deinking agents and biological enzyme deinking agents. The preparation method is simple and low in production cost. The neutral deinking agent prepared by the method can improve the whiteness of paper to 89% or above, as high as 95%; and the paper yield is greater than 80% and is as high as 83%.

Description

Technical Field

[0001] The present invention belongs to the technical field of the synthesis of anionic surfactants, and particularly relates to a mixed fatty alcohol polyoxyethylene ether phosphate, a preparation method thereof, and an application thereof. Background Art

[0002] Due to the shortage of raw material resources in the paper-making industry and the increasing emphasis on environmental protection, the recycling of waste paper is imperative. The recycled and reused waste paper has become an important fiber resource in the pulp and paper industry. The most important process for waste paper recycling is deinking. There are still a series of problems in the deinking of mixed office waste paper, such as serious environmental pollution, high deinking cost, and poor deinking effect. Therefore, it is necessary to deeply study the waste paper deinking technology to improve the waste paper deinking efficiency.

[0003] Traditional deinking is alkaline chemical deinking, that is, the pulp is disintegrated in a water body containing alkaline chemicals such as NaOH or Na2CO3, and then the subsequent washing or flotation process is used to remove the ink. However, this method is prone to the "alkali black" phenomenon, with many additives, serious pollution, and a narrow scope of application. The emergence of neutral deinking technology overcomes many drawbacks in traditional deinking, effectively avoids the alkali embrittlement of pulp, reduces the burden of wastewater treatment, and has excellent performance in the deinking process of some difficult-to-deink waste papers or some mixed waste papers. The most important component in the neutral deinking agent is the surfactant, mainly including two types. The first type is anionic surfactants, commonly including fatty acid soaps, alkyl alkanoates, fatty alcohol polyoxyethylene carboxylic (sulfuric) salts, etc. These surfactants show good foaming performance during flotation, but their ability to capture ink is insufficient and their selectivity is also poor. The second type is non-ionic surfactants, such as fatty alcohol polyoxyethylene ethers, alkylphenol polyoxyethylene ethers, fatty amine polyoxyethylene ethers, etc. These surfactants have good resistance to hard water and good deinking effect, but their foaming performance is poor and unstable. In the actual deinking application process, generally, multiple surfactants are compounded to utilize the mutual synergistic and synergistic effects between the surfactants to obtain a deinking agent with balanced performance such as deinking, dispersion, capture, and agglomeration. The fatty alcohol polyoxyethylene ether phosphate with both anionic and non-ionic properties has great potential in the application of neutral deinking agents, but the deinking effect of the neutral deinking agent prepared by using it still needs to be improved. In addition, the applicable range of fatty alcohol polyoxyethylene ether phosphate is small and it cannot play a good role in alkaline deinking and biological enzyme deinking processes.

[0004] Therefore, there is an urgent need to provide a fatty alcohol polyoxyethylene ether phosphate that can improve the deinking effect of the neutral deinking agent, broaden its applicable range, and match more deinking agents. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. For this purpose, the present invention provides a mixed fatty alcohol polyoxyethylene ether phosphate, a preparation method thereof and an application thereof. The mixed fatty alcohol polyoxyethylene ether phosphate provided by the present invention can improve the deinking effect of neutral deinking agents and is applicable to alkaline deinking agents and bio-enzyme deinking agents.

[0006] The present invention provides a preparation method of a mixed fatty alcohol polyoxyethylene ether phosphate.

[0007] Specifically, a preparation method of a mixed fatty alcohol polyoxyethylene ether phosphate includes the following steps:

[0008] Mix at least two different fatty alcohol polyoxyethylene ethers with phosphorus pentoxide, carry out a phosphorylation reaction, and carry out hydrolysis after the reaction ends to obtain a mixed fatty alcohol polyoxyethylene ether phosphate; the number of carbon atoms in the fatty chain of the fatty alcohol polyoxyethylene ether is 8-18.

[0009] Preferably, the number of carbon atoms in the fatty chain of the fatty alcohol polyoxyethylene ether is 10-16; further preferably, the fatty alcohol polyoxyethylene ether is selected from one of polyoxyethylene lauryl alcohol ether, isodecyl alcohol polyoxyethylene ether, isotridecyl alcohol polyoxyethylene ether, cetyl alcohol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, sorbitol polyoxyethylene ether, stearyl alcohol polyoxyethylene ether, etc.

[0010] Preferably, the number of ethylene oxide adducts in the fatty chain of the fatty alcohol polyoxyethylene ether is 3-18; further preferably, the number of ethylene oxide adducts in the fatty chain of the fatty alcohol polyoxyethylene ether is 5-16.

[0011] Preferably, the fatty alcohol polyoxyethylene ether is two or three kinds.

[0012] Preferably, the mass ratio of two or three kinds of the fatty alcohol polyoxyethylene ethers is (1-3):1:(0-0.3); further preferably, the mass ratio of two or three kinds of the fatty alcohol polyoxyethylene ethers is (1.5-2.5):1:(0-0.15). It should be understood that when two kinds of the fatty alcohol polyoxyethylene ethers are selected, the value of 0 is taken in the mass ratio, and when three kinds of the fatty alcohol polyoxyethylene ethers are selected, the value of 0 cannot be taken in the mass ratio. It has been found that a mixed fatty alcohol polyoxyethylene ether phosphate prepared with one kind of fatty alcohol polyoxyethylene ether as the main component and combined with another or two other fatty alcohol polyoxyethylene ethers can significantly improve the deinking effect of deinking agents (especially neutral deinking agents).

[0013] Preferably, the mass ratio of the fatty alcohol polyoxyethylene ether to the phosphorus pentoxide is (8-12):1; further preferably, the mass ratio of the fatty alcohol polyoxyethylene ether to the phosphorus pentoxide is (9.5-11):1.

[0014] Preferably, the phosphorylation reaction process is to react at 65 - 78°C for 1 - 3 hours first, and then react at 80 - 90°C for 1 - 3 hours; more preferably, the phosphorylation reaction process is to react at 70 - 78°C for 1.5 - 2.5 hours first, and then react at 82 - 88°C for 1.5 - 2.5 hours.

[0015] Preferably, the hydrolysis process is to add 15% - 25% water to the reaction system and stir for 0.5 - 2 h; more preferably, the hydrolysis process is to add 20% - 25% water to the reaction system and stir for 0.5 - 1.5 h.

[0016] The present invention also provides a mixed fatty alcohol polyoxyethylene ether phosphate.

[0017] Specifically, a mixed fatty alcohol polyoxyethylene ether phosphate is prepared by the above method.

[0018] The present invention also provides an application of the above mixed fatty alcohol polyoxyethylene ether phosphate.

[0019] Specifically, the above mixed fatty alcohol polyoxyethylene ether phosphate is used in the preparation of a deinking agent.

[0020] The present invention also provides a neutral deinking agent.

[0021] Specifically, a neutral deinking agent includes the above mixed fatty alcohol polyoxyethylene ether phosphate and a nonionic surfactant.

[0022] Preferably, the nonionic surfactant is at least one of AEO - 5, AEO - 9, AEO - 15, C18 alcohol polyoxyethylene ether (10), EO / PO block copolymer, alkylphenol polyoxyethylene ether, triphenylstyryl phenol polyoxyethylene ether, etc.

[0023] Preferably, the mass of the mixed fatty alcohol polyoxyethylene ether phosphate accounts for 30% - 80% of the total mass of the neutral deinking agent; more preferably, the mass of the mixed fatty alcohol polyoxyethylene ether phosphate accounts for 40% - 60% of the total mass of the neutral deinking agent.

[0024] The present invention changes the original way of using a single fatty alcohol polyoxyethylene ether phosphate as a surfactant and compounding it with other surfactants to form a deinking agent, and creatively prepares a mixed fatty alcohol polyoxyethylene ether phosphate, and then uses it in combination with other surfactants. This way can more precisely adjust the surface tension of anions, the size and distribution of bubbles, etc., improve the flotation efficiency and paper whiteness during waste paper treatment, greatly improve the deinking performance of the deinking agent, and also improve the hard water resistance of the solution using this product.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] (1) The present invention synthesizes a mixed phosphate ester from at least two different fatty alcohol polyoxyethylene ethers and phosphorus pentoxide. By selecting the types of fatty alcohol polyoxyethylene ethers and controlling the quality, a mixed fatty alcohol polyoxyethylene ether phosphate ester is prepared. This mixed fatty alcohol polyoxyethylene ether phosphate ester has high selectivity, high adsorption, and high resistance to hard water, can improve the deinking effect of neutral deinking agents, and has a wide application range, and can also be applied to alkaline deinking agents and biological enzyme deinking agents.

[0027] (2) Compounding the mixed fatty alcohol polyoxyethylene ether phosphate ester provided by the present invention with a non-ionic surfactant to obtain a neutral deinking agent. Using this neutral deinking agent to treat waste paper can increase the whiteness of the paper to more than 89%, up to 95%; the paper yield is greater than 80%, up to 83%.

[0028] (3) The preparation method of the mixed fatty alcohol polyoxyethylene ether phosphate ester provided by the present invention has a simple synthesis process, a simple production process, and a low production cost; there is no treatment of three wastes, which is suitable for the concept of green development. Detailed implementation manners

[0029] In order to make those skilled in the art more clearly understand the technical solutions of the present invention, the following examples are listed for illustration. It should be noted that the following examples do not limit the scope of protection required by the present invention.

[0030] The raw materials, reagents or devices used in the following examples and comparative examples can be obtained from conventional commercial channels or can be obtained by known existing methods without special instructions.

[0031] Example 1

[0032] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester, comprising the following steps:

[0033] Add 36.3 g of AEO-15 and 18.5 g of AEO-7 to the reaction kettle, stir and heat to 40 °C, slowly add 5.5 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep it warm for 2 h, and then raise the temperature to 85 °C and keep it warm for 2 h; then add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain a mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0034] A neutral deinking agent, comprising 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate ester prepared by the above method and 30 g of C18 alcohol polyoxyethylene ether (10). The preparation method of the neutral deinking agent is: adding the mixed fatty alcohol polyoxyethylene ether phosphate ester and C18 alcohol polyoxyethylene ether (10) to the reaction kettle, and stirring evenly to obtain the neutral deinking agent.

[0035] Example 2

[0036] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester, comprising the following steps:

[0037] Add 38.3 g of AEO-12 and 23.2 g of AEO-5 into a reaction kettle, stir and heat to 40 °C, slowly add 6.47 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep warm for 2 h, and then raise the temperature to 85 °C and keep warm for 2 h; subsequently add 12.1 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0038] A neutral deinking agent, comprising 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate ester prepared by the above method and 15.36 g of AEO-9. The preparation method of the neutral deinking agent is: add the mixed fatty alcohol polyoxyethylene ether phosphate ester and AEO-9 into a reaction kettle, and stir evenly to obtain the neutral deinking agent.

[0039] Example 3

[0040] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester, comprising the following steps:

[0041] Add 36.3 g of AEO-15 and 18.5 g of isomeric tridecanol polyoxyethylene (7) ether into a reaction kettle, stir and heat to 40 °C, slowly add 5.5 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep warm for 2 h, and then raise the temperature to 85 °C and keep warm for 2 h; subsequently add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0042] A neutral deinking agent, comprising 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate ester prepared by the above method and 20.18 g of AEO-9. The preparation method of the neutral deinking agent is: add the mixed fatty alcohol polyoxyethylene ether phosphate ester and AEO-9 into a reaction kettle, and stir evenly to obtain the neutral deinking agent.

[0043] Example 4

[0044] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester, comprising the following steps:

[0045] Add 36.3 g of AEO-15, 18.5 g of AEO-7, and 5.4 g of AEO-5 into a reaction kettle, stir and heat to 40 °C, slowly add 6.1 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep it warm for 2 h, and then raise the temperature to 85 °C and keep it warm for 2 h; subsequently, add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0046] A neutral deinking agent comprises 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate ester prepared by the above method and 17.1 g of C18 alcohol polyoxyethylene ether (10). The preparation method of the neutral deinking agent is: add the mixed fatty alcohol polyoxyethylene ether phosphate ester and C18 alcohol polyoxyethylene ether (10) into a reaction kettle, and prepare the neutral deinking agent after stirring evenly.

[0047] Example 5

[0048] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester comprises the following steps:

[0049] Add 36.3 g of AEO-15, 18.5 g of AEO-7, and 5.4 g of AEO-5 into a reaction kettle, stir and heat to 40 °C, Slowly Add 6.1 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, and then raise the temperature to 75 °C for heat preservation Keep it warm for 2 h, then raise the temperature to 85 °C and keep it warm for 2 h; subsequently, add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0050] A neutral deinking agent comprises 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate ester prepared by the above method and 17.1 g of nonylphenol polyoxyethylene ether. The preparation method of the neutral deinking agent is: add the mixed fatty alcohol polyoxyethylene ether phosphate ester and nonylphenol polyoxyethylene ether into a reaction kettle, and prepare the neutral deinking agent after stirring evenly.

[0051] Example 6

[0052] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate ester comprises the following steps:

[0053] Add 36.3 g of AEO-15 and 18.5 g of AEO-7 into a reaction kettle, stir and heat to 40 °C, slowly add 5.5 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep it warm for 2 h, and then raise the temperature to 85 °C and keep it warm for 2 h; subsequently, add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, and cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate ester.

[0054] An alkaline deinking agent, by weight, comprises 1 part of NaOH, 0.1 part of the above-mentioned mixed fatty alcohol polyoxyethylene ether phosphate, 2 parts of Na2SiO3, 1 part of EDTA and 2 parts of H2O2.

[0055] Example 7

[0056] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate comprises the following steps:

[0057] Add 36.3 g of AEO-15 and 18.5 g of AEO-7 into a reaction kettle, stir and heat to 40 °C, slowly add 5.5 g of phosphorus pentoxide, control the reaction temperature not exceeding 60 °C, then raise the temperature to 75 °C and keep warm for 2 h, then raise the temperature to 85 °C and keep warm for 2 h; subsequently add 11.2 g of deionized water, hydrolyze for 1 h and then end the reaction, cool to room temperature to obtain the mixed fatty alcohol polyoxyethylene ether phosphate.

[0058] A biological enzyme deinking agent contains the above-mentioned mixed fatty alcohol polyoxyethylene ether phosphate (accounting for 0.2% of the paper weight) and Novozym 476 endonuclease (concentration in pulp is 0.1 ECU / g). The two are added separately during use.

[0059] Comparative Example 1

[0060] A synthesis method of a mixed fatty alcohol polyoxyethylene ether phosphate comprises the following steps:

[0061] Add 18.5 g of AEO-7 into a reaction kettle, stir and heat to 40 °C, slowly add 1.5 g of phosphorus pentoxide, control the reaction temperature not exceeding 60 °C, then raise the temperature to 75 and keep warm for 2 h, then raise the temperature to 85 °C and keep warm for 2 h; subsequently add 3.4 g of deionized water, hydrolyze for 1 h and then end the reaction, cool to room temperature to obtain the first fatty alcohol polyoxyethylene ether phosphate.

[0062] Add 38.3 g of AEO-15 into a new reaction kettle, stir and heat to 40 °C, slowly add 3.0 g of phosphorus pentoxide, control the reaction temperature not exceeding 60 °C, then raise the temperature to 75 °C and keep warm for 2 h, then raise the temperature to 85 °C and keep warm for 2 h; subsequently add 7.8 g of deionized water, hydrolyze for 1 h and then end the reaction, cool to room temperature to obtain the second fatty alcohol polyoxyethylene ether phosphate.

[0063] Mix the two fatty alcohol polyoxyethylene ether phosphates and stir evenly to obtain the mixed fatty alcohol polyoxyethylene ether phosphate.

[0064] A neutral deinking agent, comprising 30 g of the mixed fatty alcohol polyoxyethylene ether phosphate prepared by the above method and 30 g of C18 alcohol polyoxyethylene ether (10). The preparation method of the neutral deinking agent is as follows: Add the mixed fatty alcohol polyoxyethylene ether phosphate and C18 alcohol polyoxyethylene ether (10) to a reaction kettle, and stir evenly to obtain the neutral deinking agent.

[0065] Comparative Example 2

[0066] A synthesis method of fatty alcohol polyoxyethylene ether phosphate, comprising the following steps:

[0067] Add 38.3 g of AEO-15 to a reaction kettle, stir and heat to 40 °C, slowly add 3.0 g of phosphorus pentoxide, control the reaction temperature not to exceed 60 °C, then raise the temperature to 75 °C and keep it warm for 2 h, and then raise the temperature to 85 °C and keep it warm for 2 h; Subsequently, add 7.8 g of deionized water, hydrolyze for 1 h, end the reaction, and cool to room temperature to obtain fatty alcohol polyoxyethylene ether phosphate.

[0068] A neutral deinking agent, comprising 30 g of the fatty alcohol polyoxyethylene ether phosphate prepared by the above method and 30 g of C18 alcohol polyoxyethylene ether (10). The preparation method of the neutral deinking agent is as follows: Add the fatty alcohol polyoxyethylene ether phosphate and C18 alcohol polyoxyethylene ether (10) to a reaction kettle, and stir evenly to obtain the neutral deinking agent.

[0069] Product effect test

[0070] 2. Use the neutral deinking agents prepared in Examples 1-5 and Comparative Examples 1 and 2 to conduct deinking experiments by the flotation-washing method. Deinking process parameters: The waste paper is mixed office waste paper; Pulping conditions: concentration 10%, temperature 40 °C, pulping time 30 min; Flotation conditions: concentration 1.0%, pressure 0.1-1.0 MPa, normal temperature flotation for 15 min; The usage amount of the neutral deinking agent is 0.6%.

[0071] 3. Conduct deinking experiments on the alkaline deinking agent in Example 6 by the flotation-washing method. Deinking process parameters: The waste paper is mixed office waste paper. Pulping conditions: concentration 10%, temperature 40 °C, pulping time 30 min; Flotation conditions: concentration 1.0%, flotation for 15 min at 40 °C; The usage amount of the alkaline deinking agent accounts for 1% of the waste paper mass.

[0072] 4. Conduct deinking experiments on the bio-enzyme deinking agent in Example 7 by the flotation-washing method. Deinking process parameters: The waste paper is mixed office waste paper. Add mixed fatty alcohol polyoxyethylene ether phosphate and Novozym 476 endonuclease to the waste paper pulp in a pulper, and adjust the concentration to 3.5%. Keep the temperature at 55 °C, do not adjust the pH value, react for 60 min, and then conduct flotation after the reaction. Flotation conditions: concentration 1.0%, normal temperature flotation for 15 min.

[0073] After the experiment, the whiteness and yield of the paper in each example and comparative example were tested. Specifically, a whiteness colorimeter was used to measure the whiteness (%) ISO of the paper sheet; the paper yield (%) = (the mass of the paper sheet after the experiment) / (the mass of the paper before the experiment) × 100%. The test results are shown in Table 1.

[0074] Table 1 Deinking effect of neutral deinking agent

[0075]

[0076]

[0077] As can be seen from Table 1, the mixed fatty alcohol polyoxyethylene ether phosphate prepared in the examples of the present invention can improve the deinking effect of the neutral deinking agent, has a wide application range, and can also be applied to alkaline deinking agents and biological enzyme deinking agents.

[0078] The above-described embodiments only represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A preparation method of a mixed fatty alcohol polyoxyethylene ether phosphate, characterized in that, It includes the following steps: Mix at least two different fatty alcohol polyoxyethylene ethers with phosphorus pentoxide, carry out phosphorylation reaction, and carry out hydrolysis after the reaction to obtain a mixed fatty alcohol polyoxyethylene ether phosphate; the number of carbon atoms in the fatty chain of the fatty alcohol polyoxyethylene ether is 8-18.

2. The preparation method according to claim 1, wherein The fatty alcohol polyoxyethylene ether is selected from one of lauryl alcohol polyoxyethylene ether, isodecyl alcohol polyoxyethylene ether, isotridecyl alcohol polyoxyethylene ether, cetyl alcohol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, sorbitol polyoxyethylene ether, stearyl alcohol polyoxyethylene ether, etc.

3. The preparation method according to claim 1 or 2, characterized in that, There are two or three kinds of the fatty alcohol polyoxyethylene ethers; the mass ratio of the two or three kinds of the fatty alcohol polyoxyethylene ethers is (1-3):1:(0-0.3).

4. The preparation method according to claim 3, characterized in that, The mass ratio of the fatty alcohol polyoxyethylene ether to the phosphorus pentoxide is (8-12):

1.

5. The preparation method according to claim 1 or 2, characterized in that, The process of the phosphorylation reaction is to react at 65-78 °C for 1-3 hours first, and then react at 80-90 °C for 1-3 hours.

6. A mixed fatty alcohol polyoxyethylene ether phosphate, characterized in that, It is prepared by the preparation method described in any one of claims 1-5.

7. Use of the mixed fatty alcohol polyoxyethylene ether phosphate described in claim 6 in the preparation of a deinking agent.

8. A neutral deinking agent, characterized in that, It includes the mixed fatty alcohol polyoxyethylene ether phosphate described in claim 6 and a non-ionic surfactant.

9. The neutral deinking agent according to claim 8, characterized in that The non-ionic surfactant is at least one of AEO-5, AEO-9, AEO-15, C18 alcohol polyoxyethylene ether (10), EO / PO block copolymer, alkylphenol polyoxyethylene ether, triphenylstyryl phenol polyoxyethylene ether, etc.

10. The neutral deinking agent according to claim 8 or 9, characterized in that, The mass of the mixed fatty alcohol polyoxyethylene ether phosphate accounts for 30%-80% of the total mass of the neutral deinking agent.

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