A process for deacidifying kitchen waste oil

Abstract

The present invention relates to the technical field of waste oil treatment, and provides a process for deacidifying kitchen waste oil, comprising the following steps: S1. After activating activated carbon, it is mixed evenly with chitosan and ground to obtain chitosan-modified activated carbon; S2. The chitosan-modified activated carbon is mixed evenly with a sodium hydroxide solution, filtered and dried to obtain solid base; S3. The solid base is mixed evenly with kitchen waste oil, suction filtered, washed and centrifuged to obtain the deacidified oil phase. Through the above technical solution, the problem of low deacidification rate in the deacidification process of kitchen waste oil in the related art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of waste grease treatment, and in particular to a process for deacidification of waste kitchen grease. Background Art

[0002] Waste cooking oil refers to waste edible oil, which is derived from edible oil made from a variety of biological resources. It has the characteristics of dark color, high viscosity, high acidity, etc. Its composition is very complex, and it is a mixture of various organic substances, mainly composed of fatty acid glycerides. If waste kitchen oil is discharged directly without treatment, it will cause great harm to the environment and human body. Its various oil compounds will cause serious pollution to the atmosphere, soil, water sources, etc. after mixing with waste water; waste oil contains unstable chemical substances, which will produce by-products when exposed to the environment, and the white smoke and stench produced by waste oil will seriously harm human health after being inhaled by the human body.

[0003] The unsaturated fatty acids in waste oils undergo oxidation and acidification, causing the acid value in the waste oils to exceed the standard and the generated peroxides are free fatty acids. If free fatty acids are consumed by humans, they can cause human poisoning and even induce diseases such as cancer and atherosclerosis. Therefore, it is necessary to strengthen the treatment of waste oils from catering. Waste oil deacidification refers to the process of removing free fatty acids and other organic acids from waste oils by physical or chemical methods. Through waste oil deacidification, the quality and utilization rate of waste oils can be improved and the occurrence of the above-mentioned hazards can be reduced. However, the deacidification rate of the current waste cooking oil deacidification process needs to be further improved. Therefore, a waste cooking oil deacidification process with a high deacidification rate is urgently needed. Summary of the invention

[0004] The invention provides a process for deacidification of waste kitchen oil, which solves the problem of low deacidification rate in the process for deacidification of waste kitchen oil in the related art.

[0005] The technical solution of the present invention is as follows:

[0006] The present invention provides a process for deacidification of waste cooking oil, comprising the following steps:

[0007] S1, after the activated carbon is activated, it is evenly mixed with chitosan and ground to obtain chitosan-modified activated carbon;

[0008] S2, mixing chitosan modified activated carbon and sodium hydroxide solution evenly, filtering, and drying to obtain solid alkali;

[0009] S3. Evenly mix the solid alkali and the kitchen waste oil, filter, wash and centrifuge to obtain the deacidified oil phase.

[0010] As a further technical solution, the activation treatment steps are: mixing the activated carbon and the hydrochloric acid solution evenly, filtering, washing, and drying.

[0011] As a further technical solution, the chitosan is modified chitosan modified by a modifier, and the modifier in the modified chitosan is 4-aminodiphenylmethane.

[0012] In the present invention, by defining the chitosan as modified chitosan modified by a modifier, the deacidification rate of the deacidification process for kitchen waste oil and fat is further improved.

[0013] As a further technical solution, the raw materials of the modified chitosan modified by the modifier include 4-aminodiphenylmethane and chitosan with a mass ratio of 2-5:40.

[0014] As a further technical solution, the mass ratio of the 4-aminodiphenylmethane to the chitosan is 3-4:40.

[0015] In the present invention, by defining the mass ratio of the 4-aminodiphenylmethane to the chitosan as 3-4:40, the deacidification rate of the deacidification process for kitchen waste oil and fat is further improved.

[0016] As a further technical solution, the raw materials of the chitosan-modified activated carbon include modified chitosan modified by a modifier and activated carbon with a mass ratio of 1-5:30.

[0017] As a further technical solution, the mass ratio of the modified chitosan modified by the modifier to the activated carbon is 2-3:30.

[0018] In the present invention, by defining the mass ratio of the modified chitosan modified by the modifier to the activated carbon as 2-3:30, the deacidification rate of the deacidification process for kitchen waste oil and fat is further improved.

[0019] As a further technical solution, the preparation method of the modified chitosan modified by the modifier includes the following steps:

[0020] Dissolve the modifier in a solvent, add chitosan and mix evenly, and then dry to obtain the modified chitosan modified by the modifier.

[0021] As a further technical solution, the mass ratio of the solid base to the kitchen waste oil and fat is 10-15:100.

[0022] As a further technical solution, the temperature during mixing in S3 is 60-70 °C and the time is 20-30 min.

[0023] The working principle and beneficial effects of the present invention are as follows:

[0024] In the present invention, chitosan-modified activated carbon loaded with sodium hydroxide is used as a solid base in the process of deacidifying kitchen waste oil. Chitosan is an environmentally friendly adsorbent with a natural structure. By loading sodium hydroxide on chitosan-modified activated carbon, the content of fatty acids in the waste oil is effectively reduced. At the same time, through the adjustment of the content of each component and the optimization of the process parameters during the deacidification of kitchen waste oil, the deacidification rate of the kitchen waste oil deacidification process is greatly improved. Detailed implementation mode

[0025] The following will describe the technical solutions in the embodiments of the present invention clearly and completely in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present invention.

[0026] In the following examples and comparative examples, the parameters of the raw materials are as follows:

[0027] The particle size of the activated carbon is 200 mesh;

[0028] The chitosan is chitosan nanoparticles, which are prepared by the following method:

[0029] ① Weigh a certain mass of chitosan with a deacetylation degree of 85.61% and dissolve it in an acetic acid solution with a volume fraction of 1% to prepare a chitosan solution with a concentration of 0.75 mg / mL. Stir for 1 h, adjust the pH value to 5.0, and filter with a 0.45 μm filter membrane to obtain a chitosan stock solution.

[0030] ② Prepare an aqueous solution of sodium tripolyphosphate with a concentration of 0.75 mg / mL, filter it through a 0.45 μm filter membrane to obtain a sodium tripolyphosphate stock solution. Pipette 6.0 mL of the chitosan stock solution into a 50 mL round-bottom centrifuge tube, add 1.0 mL of the sodium tripolyphosphate stock solution at a rotation speed of 600 r / min, and continuously stir for 10 min to obtain a chitosan nanoparticle suspension, which is spray-dried to obtain chitosan nanoparticles. The spray-drying conditions are as follows: flow rate 120 mL / h, drying gas flow rate 0.35 m 3 / min, spray pressure 130 kPa, inlet temperature 121 °C, outlet temperature 65 °C.

[0031] Example 1

[0032] A process for deacidifying kitchen waste oil includes the following steps:

[0033] S1. Mix 30 parts of activated carbon with 100 parts of 0.5 mol / L dilute hydrochloric acid evenly, filter, wash with deionized water until pH = 7, dry, and then mix evenly with 1 part of chitosan and grind to obtain chitosan-modified activated carbon;

[0034] S2. According to the equal - volume method, add chitosan - modified activated carbon into 10 g / L sodium hydroxide solution, stir for 12 h, filter, and dry to obtain solid base.

[0035] S3. Mix 10 parts of the solid base with 100 parts of kitchen waste oil at 60 °C for 20 min, carry out suction filtration, wash with deionized water until pH = 7, and centrifuge to obtain the deacidified oil phase.

[0036] Example 2

[0037] A process for deacidifying kitchen waste oil includes the following steps:

[0038] S1. Mix 30 parts of activated carbon with 100 parts of 0.5 mol / L dilute hydrochloric acid evenly, filter, wash with deionized water until pH = 7, dry, and then mix evenly with 5 parts of chitosan and grind to obtain chitosan - modified activated carbon.

[0039] S2. According to the equal - volume method, add chitosan - modified activated carbon into 10 g / L sodium hydroxide solution, stir for 12 h, filter, and dry to obtain solid base.

[0040] S3. Mix 15 parts of the solid base with 100 parts of kitchen waste oil at 70 °C for 30 min, carry out suction filtration, wash with deionized water until pH = 7, and centrifuge to obtain the deacidified oil phase.

[0041] Example 3

[0042] A process for deacidifying kitchen waste oil includes the following steps:

[0043] S1. Dissolve 2 parts of 4 - aminodiphenylmethane in 60 parts of methanol, add 40 parts of chitosan and mix evenly, dry to obtain modifier - modified chitosan.

[0044] S2. According to the equal - volume method, add chitosan - modified activated carbon into 10 g / L sodium hydroxide solution, stir for 12 h, filter, and dry to obtain solid base.

[0045] S3. Mix 30 parts of chitosan - modified activated carbon with 100 parts of 10 g / L sodium hydroxide solution evenly, filter, and dry to obtain solid base.

[0046] S4. Mix 10 parts of the solid base with 100 parts of kitchen waste oil at 60 °C for 20 min, carry out suction filtration, wash with deionized water until pH = 7, and centrifuge to obtain the deacidified oil phase.

[0047] Example 4

[0048] The difference from Example 3 is only that: 5 parts of 4 - aminodiphenylmethane.

[0049] Example 5

[0050] The difference from Example 3 is only that: 3 parts of 4-aminodiphenylmethane.

[0051] Example 6

[0052] The difference from Example 3 is only that: 4 parts of 4-aminodiphenylmethane.

[0053] Example 7

[0054] The difference from Example 6 is only that: 5 parts of modifier-modified chitosan.

[0055] Example 8

[0056] The difference from Example 6 is only that: 2 parts of modifier-modified chitosan.

[0057] Example 9

[0058] The difference from Example 6 is only that: 3 parts of modifier-modified chitosan.

[0059] Comparative Example 1

[0060] A process for deacidifying kitchen waste oil and grease includes the following steps:

[0061] S1. Mix 30 parts of activated carbon with 100 parts of 0.5 mol / L dilute hydrochloric acid evenly, filter, wash with deionized water until the pH = 7, dry, and then add it to 10 g / L sodium hydroxide solution according to the equal-volume method, stir for 12 h, filter, and dry to obtain solid base;

[0062] S2. Mix 10 parts of the solid base with 100 parts of kitchen waste oil and grease at 60 °C for 20 min, filter with suction, wash with deionized water until the pH = 7, and centrifuge to obtain the deacidified oil phase.

[0063] Comparative Example 2

[0064] A process for deacidifying kitchen waste oil and grease includes the following steps:

[0065] S1. Mix 30 parts of activated carbon and 20 parts of clay with 100 parts of 0.5 mol / L dilute hydrochloric acid evenly respectively, filter, wash with deionized water until the pH = 7, and dry to obtain activated activated carbon and activated clay;

[0066] S2. Mix 6 parts of the activated activated carbon and 4 parts of the activated clay evenly, and then put them into 10 g / L sodium hydroxide solution according to the equal-volume method, stir for 12 h, filter, and dry to obtain solid base;

[0067] S3. Mix 10 parts of solid base with 100 parts of kitchen waste oil at 60 °C for 20 min, filter by suction, wash with deionized water until the pH = 7, and centrifuge to obtain the deacidified oil phase.

[0068] Test example

[0069] The kitchen waste oil before and after deacidification treatment using the deacidification processes of Examples 1-9 and Comparative Examples 1-2 was determined for acid value according to the standard of the first method in GB 5009.229-2016, and the deacidification rate was calculated according to the following formula;

[0070] Deacidification rate = (acid value of waste oil before treatment - acid value of waste oil after treatment) ÷ acid value of waste oil before treatment × 100%;

[0071] The results are shown in Table 1.

[0072] Table 1 Deacidification test results of Examples 1-9 and Comparative Examples 1-2

[0073]

[0074] Compared with Comparative Examples 1-2, in Example 1, the activated carbon in the kitchen waste oil deacidification process was chitosan-modified activated carbon. As a result, the deacidification rate of Example 1 was greater than that of Comparative Examples 1-2, indicating that using chitosan-modified activated carbon can improve the deacidification rate of the kitchen waste oil deacidification process.

[0075] The deacidification rates of Examples 3-6 were greater than that of Example 1, indicating that using chitosan as a modifier to modify chitosan further improved the deacidification rate of the kitchen waste oil deacidification process.

[0076] The deacidification rates of Examples 5-6 were greater than those of Examples 3-4, indicating that when the mass ratio of 4-aminodiphenylmethane to chitosan was 3-4:40, the deacidification rate of the kitchen waste oil deacidification process was further improved.

[0077] The deacidification rates of Examples 8-9 were greater than those of Examples 6-7, indicating that when the mass ratio of modified chitosan to activated carbon was 2-3:30, the deacidification rate of the kitchen waste oil deacidification process was further improved.

[0078] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for deacidifying kitchen waste oil, characterized in that, It includes the following steps: S1. After activating the activated carbon, mix it evenly with chitosan and grind to obtain chitosan-modified activated carbon; S2. Mix the chitosan-modified activated carbon evenly with sodium hydroxide solution, filter and dry to obtain solid base; S3. Mix the solid base evenly with kitchen waste oil, filter with suction, wash and centrifuge to obtain the deacidified oil phase; The chitosan is chitosan modified by a modifier, and the modifier in the chitosan modified by the modifier is 4-aminodiphenylmethane; The preparation method of the chitosan modified by the modifier includes the following steps: Dissolve the modifier in a solvent, add chitosan and mix evenly, and dry to obtain chitosan modified by the modifier, wherein the raw material chitosan is chitosan nanoparticles.

2. The degreasing process for kitchen waste oil according to claim 1, characterized in that, The steps of the activation treatment are: mix the activated carbon evenly with hydrochloric acid solution, filter, wash and dry.

3. The deacidification process for kitchen waste oil according to claim 1, characterized in that, The raw materials of the chitosan modified by the modifier include 4-aminodiphenylmethane and chitosan with a mass ratio of 2-5:

40.

4. The deacidification process for kitchen waste oil according to claim 3, characterized in that, The mass ratio of the 4-aminodiphenylmethane and chitosan is 3-4:

40.

5. A process for deacidifying kitchen waste oil according to claim 4, characterized in that, The raw materials of the chitosan-modified activated carbon include chitosan modified by a modifier and activated carbon with a mass ratio of 1-5:

30.

6. The deacidification process of kitchen waste oil according to claim 5, characterized in that, The mass ratio of the chitosan modified by the modifier and the activated carbon is 2-3:

30.

7. A process for deacidifying kitchen waste oil according to claim 1, characterized in that, The mass ratio of the solid base and the kitchen waste oil is 10-15:

100.

8. A process for deacidifying kitchen waste oil according to claim 1, characterized in that, The temperature during mixing in S3 is 60-70 °C and the time is 20-30 min.

Images