Preparation of Alkylcyclohexanol Polyoxyethylene Ether Emulsifier and Application Thereof

Abstract

The disclosure discloses preparation and application of an alkylcyclohexanol polyoxyethylene ether emulsifier, and belongs to the technical field of surfactants. By performing ethylene oxide adducting on alkylcyclohexanol polyoxyethylene ether (1-3) and using a strong alkaline suspension dispersed in the solvent and alkylcyclohexanol polyoxyethylene ether (1-3) as a catalyst, nonionic surfactants alkylcyclohexanol polyoxyethylene ether (5-17) are synthesized. The products all have good characteristics of nonionic surfactants, and contain lower content of polyethylene. The products such as nonylcyclohexanol ethoxylate (7) and nonylcyclohexanol ethoxylate (9) have emulsifying properties similar to the emulsifying property of nonylphenol ethoxylate (10), and therefore can substitute for nonylphenol ethoxylate (10) as an emulsifier.

Claims

1. A method of preparing an alkylcyclohexanol polyoxyethylene ether emulsifier, wherein the alkylcyclohexanol polyoxyethylene ether emulsifier has a structure shown in Formula I as follows: ##STR00004## wherein R is a straight-chain or branched alkyl group having a carbon number of C.sub.6-C.sub.15, and n is 5-17; wherein in the method, an ethoxylation reaction of an alkylcyclohexanol polyoxyethylene ether with an adduct number of 1-3 is catalyzed by a basic catalyst, and the alkylcyclohexanol polyoxyethylene ether with the adduct number of 1-3 has a structural formula shown in Formula II as follows: ##STR00005## wherein in Formula II, R is a straight-chain or branched alkyl group having a carbon number of C.sub.6-C.sub.15, and n is 1-3; the method comprising: mixing the alkylcyclohexanol polyoxyethylene ether with the ethylene oxide adduct number of 1-3 with water and the catalyst to prepare a catalyst suspension, then placing the alkylcyclohexanol polyoxyethylene ether with the ethylene oxide adduct number of 1-3 and the catalyst suspension into a reactor, stirring and heating to a reaction temperature, dehydrating in vacuum until a water content is lower than 0.1%; keeping a system pressure at 0.1-0.5 Mpa when slowly adding ethylene oxide into the reactor, controlling the reaction temperature to be constant, continuing to stir for another 0.5-1 h after the pressure in the reactor does not drop any more, and then ending the heating; and after the temperature in the reactor is cooled to room temperature, neutralizing the reaction mixture in the reactor by acetic acid to pH 6.5-7 and then discharging.

2. The method of claim 1, wherein a molar ratio of a raw material NCEO.sub.1-3 to the ethylene oxide is 1:(4-14).

3. The method of claim 1, wherein the basic catalyst is one or more of KOH, NaOH, LiOH, K.sub.2CO.sub.3, Na.sub.2CO.sub.3, CH.sub.3OK or CH.sub.3ONa.

4. The method of claim 1, wherein the catalyst suspension is a disperse system comprising the alkylcyclohexanol polyoxyethylene ether with the ethylene oxide adduct number of 1-3 and the basic catalyst, and the basic catalyst is one or more of KOH, NaOH, LiOH, K.sub.2CO.sub.3, Na.sub.2CO.sub.3, CH.sub.3OK or CH.sub.3ONa.

5. The method of claim 1, wherein the mixing the alkylcyclohexanol polyoxyethylene ether with the ethylene oxide adduct number of 1-3 with water and the catalyst to prepare the catalyst suspension comprises: dissolving the catalyst in a solvent at room temperature to reach a final mass concentration of the catalyst in the catalyst suspension is 15-25%; and then adding NCEO.sub.1-3 with a mass accounting for 20-50% of a mass of the catalyst to the catalyst suspension, and intensely stirring the catalyst suspension to evenly disperse the NCEO.sub.1-3.

6. The method of claim 4, wherein the mixing the alkylcyclohexanol polyoxyethylene ether with the ethylene oxide adduct number of 1-3 with water and the catalyst to prepare the catalyst suspension comprises: dissolving the catalyst in a solvent at room temperature to reach a final mass concentration of the catalyst in the catalyst suspension is 15-25%; and then adding NCEO.sub.1-3 of 20 wt %-50 wt % of the catalyst in the catalyst suspension, and intensely stirring the catalyst suspension to evenly disperse the NCEO.sub.1-3.

7. The method of claim 5, wherein when the catalyst is one or two of KOH, NaOH, LiOH, K.sub.2CO.sub.3 and Na.sub.2CO.sub.3, the solvent is water; and when the catalyst is one or two of CH.sub.3OK and CH.sub.3ONa, the solvent is a 70% ethanol aqueous solution.

8. The method of claim 1, wherein a mass of the catalyst calculated according to a dry basis accounts for 0.1-1.0% of a total mass of NCEO.sub.1-3.

9. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 1.

10. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 2.

11. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 3.

12. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 4.

13. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 5.

14. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 6.

15. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 7.

16. An alkylcyclohexanol polyoxyethylene ether emulsifier prepared according to the method of claim 8.

17. A method of use of the alkylcyclohexanol polyoxyethylene ether emulsifier of claim 9, comprising: using the alkylcyclohexanol polyoxyethylene ether emulsifier as a dispersing agent and a wetting agent to prepare oil-in-water type emulsions.

18. The method of claim 17, wherein oil phases of the oil-in-water type emulsions comprise liquid paraffin, biodiesel, xylene, animal fat, vegetable oil or dimethyl silicone oil.

19. A method of use of the alkylcyclohexanol polyoxyethylene ether emulsifier of claim 10, comprising: using the alkylcyclohexanol polyoxyethylene ether emulsifier as a dispersing agent and a wetting agent to prepare oil-in-water type emulsions.

20. A method of use of the alkylcyclohexanol polyoxyethylene ether emulsifier of claim 11, comprising: using the alkylcyclohexanol polyoxyethylene ether emulsifier as a dispersing agent and a wetting agent to prepare oil-in-water type emulsions.

Description

BRIEF DESCRIPTION OF FIGURES

[0021] FIG. 1 is an FTIR spectrogram (IR) of nonylcyclohexanol ethoxylate (7) (NCEO.sub.7).

[0022] FIG. 2 is a mass spectrogram (ESI-MS) of nonylcyclohexanol ethoxylate (7) (NCEO.sub.7).

[0023] FIG. 3 shows emulsifying properties of nonylcyclohexanol ethoxylates NCEO.sub.n (n=7, 9, 11 and 13) (reference substance: nonylphenol ethoxylate NPEO.sub.10).

DETAILED DESCRIPTION

[0024] With the industrial commodities surfactant, nonylphenol ethoxylate NPEO.sub.n as the reference substances in the aspect of the surface activities, the NCEO.sub.n are synthesized and their emulsifying properties are detected, and the obtained alkylcyclohexanol polyoxyethylene ether surfactants provide a structure and application basis of an emulsifier.

[0025] The content of free polyethylene glycol in the products is detected according to the Weibull method (refer to the China national standard, GB 5560-2003). During the vacuum dehyration, the water content of a reaction mixture is measured according to the Karl Fischer assay (refer to the China national standard, GB/T 7380). The remained ethylene oxide in the products is detected with gas chromatography (refer to the China national standard, GB/T 16886.7-2001).

[0026] Measurement of emulsifying ability: Deemulsification time is used to indicate the emulsifying ability. Longer time represents better emulsifying ability. Liquid paraffin, biodiesel, xylene, olive oil or dimethyl silicone oil was used as oil phase substance, respectively. 40 mL of 1 g/L surfactant solution and 40 mL of the oil phase substance are placed in the mixing glass cylinder with a stopper. Firmly plug the mixing cylinder with the stopper, shaking vertically for five times followed by 1 min of standing, and then shaking vertically another five followed by 1 min of standing, keep the same strength for each shaking; which is repeatedly executed five times. After the fifth shaking ends, instantly started the timing, and the time for 10 mL of the water phase was separated to the lower layer is referred as the deemulsification time.

[0027] Measurement of cloud point: The cloud point assay refers to the China national standard of GB/T 5559-2010. A test tube containing 0.5% surfactant aqueous solution is placed into a water bath to be slowly heated (or cooled), a temperature corresponding to the time when the solution just becomes turbid (the heating assay) or turns into clear from completely turbid (the cooling assay) is referred to as a cloud point of a test sample. The cloud point of NPEO.sub.10 is 61.1 C.

SYNTHESIS AND APPLICATION OF NONYLCYCLOHEXANOL ETHOXYLATES ARE TAKEN AS EXAMPLES AS FOLLOWS

Example 1 Preparation of Nonylcyclohexanol Ethoxylate (7) Under Catalysis of KOH Catalyst Suspension

[0028] 5 g of KOH was dissolved in 15 mL of water at room temperature, and then 2 g of nonylcyclohexanol ethoxylate (1) was added to the solution and intensely stirred to be evenly dispersed to obtain the KOH catalyst suspension.

[0029] 1 kg of nonylcyclohexanol ethoxylate (1) was placed into the reactor, and the KOH catalyst suspension was added under stirring. The reaction mixture was heated to 90 C. and dehydrated in vacuum for 0.2 h. Then a system pressure was kept at 0.3 Mpa when 0.98 kg of ethylene oxide (a molar ratio of NCEO.sub.1:EO=1:6) was slowly added into the reactor, stirring for another 0.5 h at 120 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to a pH7 and was then discharged. The product nonylcyclohexanol ethoxylate (7) possess a cloud point of 62.5 C., a polyethylene glycol content of 1.1% and an ethylene oxide residual of 7 ppm. The FTIR spectrogram is shown in FIG. 1, the mass spectrogram is shown in FIG. 2, and the emulsifying properties are shown in FIG. 3.

Example 2 Preparation of Nonylcyclohexanol Ethoxylate (9) Under Catalysis of KOH Catalyst Suspension

[0030] 6 g of KOH was dissolved in 15 mL of water at the room temperature, and then 3 g of nonylcyclohexanol ethoxylate (1) was added to the solution and intensely stirred to be evenly dispersed to obtain the KOH catalyst suspension.

[0031] 1 kg of nonylcyclohexanol ethoxylate (1) was placed into a reactor, and the KOH catalyst suspension was added into the reactor under stirring. The reaction mixture was then heated to 100 C. and dehydrated in vacuum for 0.2 h. Then the reaction pressure was kept at 0.3 Mpa. 1.3 kg of ethylene oxide (a molar ratio of NCEO.sub.1:EO=1:8) was slowly added into the reactor. Stirring for another 0.5 h at 125 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH 6.5 and was then discharged. The product nonylcyclohexanol ethoxylate (9) possess a cloud point of 69.4 C., a polyethylene glycol content of 0.98% and an ethylene oxide residual of 7.2 ppm. The emulsifying properties of the product (recorded as NCEO.sub.9) are shown in FIG. 3 of the specification.

Comparative Example Preparation of Nonylcyclohexanol Ethoxylate (9) Under Catalysis of KOH Powder

[0032] 1 kg of nonylcyclohexanol ethoxylate (1) was placed into a reactor, and 6 g of KOH was added into the reactor under stirring. The reaction mixture was then heated to 100 C. and dehydrated in vacuum for 0.1 h. Then the reaction pressure was kept at 0.3 Mpa. 1.3 kg of ethylene oxide was slowly added into the reactor, stirring for another 0.5 h at 125 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH 6.5 and was then discharged. The product nonylcyclohexanol ethoxylate (9) possess a cloud point of 72 C., a polyethylene glycol content of 16% and an ethylene oxide residual of 120 ppm. The emulsifying properties of the product (recorded as NCEO.sub.9(I)) are shown in FIG. 3 of the specification.

Comparative Example Preparation of Nonylcyclohexanol Ethoxylate (9) Under Catalysis of KOH Aqueous Solution

[0033] 6 g of KOH was dissolved in 15 mL of water at room temperature to be stirred to obtain the KOH catalyst aqueous solution.

[0034] 1 kg of nonylcyclohexanol ethoxylate (1) was placed into a reactor, and the KOH catalyst aqueous solution was added into the reactor under stirring. The reaction mixture was then heated to 100 C. and dehydrated in vacuum for 0.1 h. Then the reaction pressure was kept at 0.3 Mpa. 1.3 kg of ethylene oxide was slowly added into the reactor, stirring for another 0.5 h at 125 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH 6.5 and was then discharged. The product nonylcyclohexanol ethoxylate (9) possess a cloud point of 75 C., a polyethylene glycol content of 20% and an ethylene oxide residual of 7.0 ppm.

Example 3 Preparation of Nonylcyclohexanol Ethoxylate (13) Under Catalysis of CH.SUB.3.OK Suspension

[0035] 6 g of CH.sub.3OK was dissolved in 15 mL of 70% ethanol aqueous solution at the room temperature, and then 1 g of nonylcyclohexanol ethoxylate (3) was added to the solution and intensely stirred to be evenly dispersed to obtain the CH.sub.3OK catalyst suspension.

[0036] 1 kg of nonylcyclohexanol ethoxylate (3) was placed into a reactor, and the CH.sub.3OK catalyst suspension was added into the reactor under stirring. The reaction mixture was then heated to 140 C. and dehydrated in vacuum for 0.2 h. Then the reaction pressure was kept at 0.4 Mpa. 1.23 kg of ethylene oxide (a molar ratio of NCEO.sub.3:EO=1:10) was slowly added into the reactor. Stirring for another 1 h at 140 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH 6.5 and was then discharged. The product nonylcyclohexanol ethoxylate (13) possess a cloud point of 83.9 C., a polyethylene glycol content of 2.1% and an ethylene oxide residual of 6.3 ppm. The emulsifying properties of the product (recorded as NCEO.sub.13) are shown in FIG. 3 of the specification.

Example 4 Preparation of Nonylcyclohexanol Ethoxylate (7) Under Catalysis of CH.SUB.3.OK Suspension

[0037] 4 g of CH.sub.3OK was dissolved in 12 mL of 70% ethanol aqueous solution at the room temperature, and then 1 g of nonylcyclohexanol ethoxylate (2) was added to the solution and intensely stirred to be evenly dispersed to obtain the CH.sub.3OK catalyst suspension.

[0038] 1 kg of nonylcyclohexanol ethoxylate (2) was placed into a reactor, and a CH.sub.3OK catalyst suspension was added into the reactor under stirring. The reaction mixture was then heated to 90 C. and dehydrated in vacuum for 0.2 h. Then the reaction pressure was kept at 0.3 Mpa. 0.70 kg of ethylene oxide was slowly added into the reactor. Stirring for another 1 h at 120 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH7 and was then discharged. The product nonylcyclohexanol ethoxylate (7) possess a cloud point of 63.5 C., a polyethylene glycol content of 2.6% and an ethylene oxide residual of 2.3 ppm.

Example 5 Preparation of Nonylcyclohexanol Ethoxylate (7) Under Catalysis of NaHCO.SUB.3 .Suspension

[0039] 5 g of NaHCO.sub.3 was dissolved in 15 mL of water at the room temperature, and then 2 g of nonylcyclohexanol ethoxylate (2) was added to the solution and intensely stirred to be evenly dispersed to obtain the NaHCO.sub.3 catalyst suspension.

[0040] 1 kg of nonylcyclohexanol ethoxylate (2) was placed into a reactor, and the NaHCO.sub.3 catalyst suspension was added into the reactor under stirring. The reaction mixture was then heated to 90 C. and dehydrated in vacuum for 0.2 h. Then the reaction pressure was kept at 0.3 Mpa when 0.70 kg of ethylene oxide was slowly added into the reactor. Stirring for another 0.5 h at 120 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH7 and was then discharged. The product nonylcyclohexanol ethoxylate (7) possess a cloud point of 69 C., a polyethylene glycol content of 28.2% and an ethylene oxide residual of 26 ppm.

[0041] Under the above same reaction conditions, nonylcyclohexanol ethoxylates (7) are prepared under catalysis of Na.sub.2CO.sub.3 and NaOH correspondingly; and the obtained products nonylcyclohexanol ethoxylates (7) have cloud points of 63 C. and 62.6 C., polyethylene glycol contents of 1.2% and 1.0% and ethylene oxide residual quantities of 8 ppm and 5 ppm correspondingly.

[0042] Under the same reaction conditions, NaHCO.sub.3 cannot effectively catalyze the reaction, and by-products polyethylene glycol and residual ethylene oxide are relatively high in content, which may be a cause of weak alkalinity of NaHCO.sub.3 or may need to increase the consumption of weak base. However, it can be seen in Example 5 that nevertheless, due to the adoption of the suspension for catalysis, residual ethylene oxide in the product still has a catalysis effect better than that of base powder of Comparative example in Example 2.

[0043] In the following Comparative example, reaction was repeated after the increase of a NaHCO.sub.3 consumption, reaction temperature and ageing time.

Comparative Example Preparation of Nonylcyclohexanol Ethoxylate (7) Under Catalysis of NaHCO.SUB.3.Suspension after Increase of NaHCO.SUB.3 .Consumption, Reaction Temperature and Ageing Time on Basis of Example 5

[0044] 10 g of NaHCO.sub.3 was dissolved in 30 mL of water at the room temperature, and then 4 g of nonylcyclohexanol ethoxylate (2) was added to the solution and intensely stirred to be evenly dispersed to obtain the NaHCO.sub.3 catalyst suspension.

[0045] 1 kg of nonylcyclohexanol ethoxylate (2) was placed into a reactor, and the NaHCO.sub.3 catalyst suspension was added into the reactor under stirring. The reaction mixture was then heated to 130 C. and dehydrated in vacuum for 1 h. Then the reaction pressure was kept at 0.5 Mpa when 0.70 kg of ethylene oxide was slowly added into the reactor. Stirring for another 2 h at 130 C. until the reaction pressure in the reactor does not drop. Keep stirring until the reaction mixture was cooled to the room temperature. The reaction mixture was then neutralized by acetic acid to pH7 and was then discharged. The product nonylcyclohexanol ethoxylate (7) has a cloud point of 73.1 C., a polyethylene glycol content of 25.2% and an ethylene oxide residual of 20 ppm.

[0046] It can be seen that even after the increase of the NaHCO.sub.3 consumption, reaction temperature and ageing time, the NaHCO.sub.3 suspension still cannot perform catalysis well to prepare the nonylcyclohexanol ethoxylate. Thus, it is not the problem of NaHCO.sub.3 consumption, and the cause remains to be studied.

Example 6 Preparation of Emulsions from Nonylcyclohexanol Ethoxylate Surfactant and Several Typical Oil Products

[0047] With liquid paraffin, biodiesel, xylene, olive oil and dimethyl silicone oil as oil phase substance, respectively, and a 0.1% nonylcyclohexanol ethoxylate surfactant as an emulsifier, emulsifying abilities, namely stability properties of the obtained emulsions, are shown in FIG. 3 of the specification.

[0048] FIG. 3 shows that emulsifying abilities of nonylcyclohexanol ethoxylates (7) and (9) for several typical oils are close to the emulsifying ability of NPEO.sub.10. Specifically, the emulsifying ability of NCEO.sub.7 for mineral oil or vegetable oil is higher than that of NPEO.sub.10, the emulsifying ability of NCEO.sub.7 for biodiesel is consistent with the emulsifying ability of NPEO.sub.10. Therefore, NCEO.sub.7 and NCEO.sub.9 can be used for substituting for NPEO.sub.10 as an emulsifier for these oil emulsions.