Leather bio-based degreasing agent and preparation method thereof

Abstract

The invention belongs to the field of leather making cleaning, and particularly relates to a leather bio-based degreasing agent and a preparation method thereof. The bio-based degreasing agent for leather comprises the following raw materials in percentage by weight: 18-22% of lipase, 38-42% of a bio-based surfactant, 0.1-0.2% of an enzyme activator, 1-3% of an enzyme stabilizer, 1-3% of a pH stabilizer and the balance of water. According to the leather bio-based degreasing agent disclosed by the invention, lipase and a bio-based surfactant (a metabolite with certain surface activity is secreted in a metabolic process when microorganisms are cultured under a certain condition) are organically combined, so that the lipase and the bio-based surfactant play a synergistic effect; and according to the detection result, the degreasing rate of the products obtained in the embodiments 1-3 is far higher than that of similar products sold in the market. In addition, the bio-based surfactant, lipase and other bio-based materials have great advantages in the aspects of carbon emission reduction, reproducibility and the like compared with a traditional petroleum-based surfactant, and popularization is more facilitated.

Description

Technical Field

[0001] The invention belongs to the field of leather cleaning, and in particular relates to a leather bio-based degreasing agent and a preparation method thereof. Background Art

[0002] When the oil in the leather is not removed cleanly during the leather making process, it is easy to cause the problem of oil frost. Therefore, degreasing plays a very important role in raw leathers rich in oil. At present, the main degreasing methods are lipase degreasing and surfactant degreasing. Lipase degreasing is to hydrolyze the oil in the skin by lipase to produce glycerol, fatty acids, monoglycerides and diglycerides to achieve the purpose of degreasing. Surfactant degreasing is to emulsify the oil in the skin by emulsification to achieve the purpose of degreasing.

[0003] Lipase itself is a bio-based material, and its degreasing is more environmentally friendly, but lipase preparations do not hydrolyze the oil in the skin to a high degree, and the degreasing effect is poor, so it usually needs to be used with a surfactant. However, currently, the surfactants are still mainly petroleum-based, such as sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether.

[0004] Therefore, based on this, the technical solution of the present invention is proposed. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a leather bio-based degreasing agent, which comprises the following raw materials: lipase, a bio-based surfactant, an enzyme activator, an enzyme stabilizer, a pH stabilizer and water.

[0006] Preferably, the leather bio-based degreasing agent comprises the following raw materials in weight percentage: 18-22% lipase, 38-42% bio-based surfactant, 0.1-0.2% enzyme activator, 1-3% enzyme stabilizer, 1-3% pH stabilizer and the balance water.

[0007] Preferably, the lipase is a neutral lipase or an alkaline lipase.

[0008] Preferably, the bio-based surfactant is one or both of a sophorolipid bio-based surfactant and a rhamnolipid bio-based surfactant.

[0009] Preferably, the enzyme activator is calcium chloride or magnesium chloride.

[0010] Preferably, the enzyme stabilizer is 4-formylphenylboronic acid, boric acid or propylene glycol.

[0011] Preferably, the pH stabilizer is sodium citrate or sodium tartrate.

[0012] Based on the same technical concept, another scheme of the present invention is to provide a method for preparing a leather bio-based degreasing agent, wherein the preparation method comprises: uniformly mixing all raw materials to obtain the leather bio-based degreasing agent.

[0013] Preferably, all raw materials are mixed uniformly at a temperature of 25 to 30° C. and a rotation speed of 40 to 60 r / min to obtain the leather bio-based degreasing agent.

[0014] The beneficial effects of the present invention are:

[0015] The leather bio-based degreasing agent described in the present invention organically combines lipase and bio-based surfactant (refers to metabolites with certain surface activity secreted during the metabolism of microorganisms when they are cultured under certain conditions) so that the two can play a synergistic role; and from the test results, it can be seen that the degreasing rate of the products obtained in Examples 1 to 3 is much higher than that of similar products on the market.

[0016] In addition, bio-based materials such as bio-based surfactants and lipases have great advantages over traditional petroleum-based surfactants in terms of carbon emission reduction and renewability, and are more conducive to promotion. DETAILED DESCRIPTION

[0017] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0018] Example 1

[0019] This embodiment provides a method for preparing a leather bio-based degreasing agent, the preparation method comprising the following steps:

[0020] (1) 20 g of neutral lipase, 40 g of sophorolipid biosurfactant, 0.1 g of calcium chloride, 2 g of 4-formylphenylboric acid, 2 g of sodium citrate and 35.9 g of water were mixed to obtain a premix;

[0021] (2) Stirring the premix at a temperature of 25° C. and a rotation speed of 60 r / min to obtain a leather bio-based degreasing agent after the system is uniform.

[0022] Example 2

[0023] This embodiment provides a method for preparing a leather bio-based degreasing agent, the preparation method comprising the following steps:

[0024] (1) 20 g of neutral lipase, 40 g of rhamnose bio-based surfactant, 0.1 g of magnesium chloride, 1 g of boric acid, 1 g of propylene glycol, 2 g of sodium tartrate and 35.9 g of water were mixed to obtain a premix;

[0025] (2) Stirring the premix at a temperature of 30° C. and a rotation speed of 40 r / min to obtain a leather bio-based degreasing agent after the system is uniform.

[0026] Example 3

[0027] This embodiment provides a method for preparing a leather bio-based degreasing agent, the preparation method comprising the following steps:

[0028] (1) 20 g of neutral lipase, 20 g of rhamnose bio-based surfactant, 20 g of sophorolipid bio-based surfactant, 0.1 g of calcium chloride, 1 g of 4-formylphenylboric acid, 1 g of propylene glycol, 2 g of sodium citrate and 35.9 g of water were mixed to obtain a premix;

[0029] (2) Stirring the premix at a temperature of 30° C. and a rotation speed of 40 r / min to obtain a leather bio-based degreasing agent after the system is uniform.

[0030] Degreasing effect verification example 1

[0031] Degreasing scheme: 100 kg of sheepskin after soaking and fleshing was added to a drum, and then 200 kg of water was added, the temperature was adjusted to 38°C, 3 kg of the prepared degreasing agent (leather bio-based degreasing agent obtained in Examples 1 to 3 and commercially available degreasing agent) was added, and the mixture was rotated for 120 minutes, and then drained; then 200 kg of water at a temperature of 38°C was added, and the mixture was rotated for 20 minutes, and then the mixture was drained and the leather embryo was taken out. The residual oil content in the leather embryo was sampled and measured, and the degreasing rate was calculated.

[0032] The degreasing process is shown in Table 1.

[0033] Table 1

[0034] Process Material Dosage / % temperature Operation time Degreasing water 200 38℃ Solution 1 Commercial degreasing agent 3 / Rotate for 120 minutes Solution 2 Example 1 3 / Rotate for 120 minutes Option 3 Example 2 3 / Rotate for 120 minutes Option 4 Example 3 3 / Rotate for 120 minutes Washing 1 water 200 38℃ Rotate for 20 minutes Wash 2 water 200 38℃ Rotate for 20 minutes

[0035] Note: The commercially available degreaser is Dawilan DG-NH (petroleum-based non-ionic degreaser).

[0036] The results of the fat removal rate are shown in Table 2.

[0037] Table 2

[0038] Group Commercial degreasing agent Example 1 Example 2 Example 3 Degreasing rate / % 30.64％ 49.15％ 37.17％ 44.42％

[0039] Degreasing effect verification example 2

[0040] Degreasing plan: 100 kg of pre-soaked and fleshed cowhide is added to a drum, and then 150 kg of water is added, the temperature is adjusted to 25°C, 1 kg of the prepared degreasing agent (the leather bio-based degreasing agent obtained in Examples 1 to 3 and a commercially available degreasing agent, respectively) and 0.5 kg of soda ash are added, and the drum is rotated for 120 minutes, then rotated for 1 minute and stopped for 60 minutes, and drained the next day; then 150 kg of water at 25°C is added, and after rotating for 20 minutes, the drum is drained, the leather embryo is taken out for sampling to determine the residual oil content in the leather embryo, and the degreasing rate is calculated.

[0041] The degreasing process is shown in Table 3.

[0042] Table 3

[0043] Process Material Dosage / % temperature Operation time Degreasing water 150 25℃ soda ash 0.5 Solution 1 Commercial degreasing agent 1 / Rotate for 120 minutes Solution 2 Example 1 1 / Rotate for 120 minutes Option 3 Example 2 1 / Rotate for 120 minutes Option 4 Example 3 1 / Rotate for 120 minutes Turn for 1 minute and stop for 60 minutes Until the next day drain Washing 1 water 150 25℃ Rotate for 20 minutes Wash 2 water 150 25℃ Rotate for 20 minutes

[0044] Note: The commercially available degreaser is Dawilan DG-NH (petroleum-based non-ionic degreaser).

[0045] The results of the fat removal rate are shown in Table 4.

[0046] Table 4

[0047] Group Commercial degreasing agent Example 1 Example 2 Example 3 Degreasing rate / % 38.33％ 50.11％ 40.42％ 46.31％

[0048] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A bio-based leather degreasing agent, characterized in that: The raw materials include lipase, bio-based surfactant, enzyme activator, enzyme stabilizer, pH stabilizer and water.

2. The leather bio-based degreasing agent according to claim 1, characterized in that: The invention comprises the following raw materials in weight percentage: 18-22% of lipase, 38-42% of bio-based surfactant, 0.1-0.2% of enzyme activator, 1-3% of enzyme stabilizer, 1-3% of pH stabilizer and the balance of water.

3. The leather bio-based degreasing agent according to claim 1 or 2, characterized in that: The lipase is neutral lipase or alkaline lipase.

4. The leather bio-based degreasing agent according to claim 1 or 2, characterized in that: The bio-based surfactant is one or both of a sophorolipid bio-based surfactant and a rhamnolipid bio-based surfactant.

5. The leather bio-based degreasing agent according to claim 1 or 2, characterized in that: The enzyme activator is calcium chloride or magnesium chloride.

6. The bio-based leather degreasing agent according to claim 1 or 2, characterized in that: The enzyme stabilizer is 4-formylphenylboronic acid, boric acid or propylene glycol.

7. The bio-based leather degreasing agent according to claim 1 or 2, characterized in that: The pH stabilizer is sodium citrate or sodium tartrate.

8. The method for preparing the bio-based leather degreasing agent according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: all raw materials are mixed evenly to obtain the leather bio-based degreasing agent.

9. The preparation method according to claim 8, characterized in that: Under the conditions of a temperature of 25 to 30° C. and a rotation speed of 40 to 60 r / min, all raw materials are mixed uniformly to obtain the leather bio-based degreasing agent.