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 (NCEO) emulsifier, wherein the NCEO emulsifier has a structure shown in Formula I as follows: ##STR00004## Formula I, wherein R is a straight-chain or branched alkyl group having a carbon number of C.sub.6-C.sub.15, and wherein n is 5 to 17; which comprises: conducting an ethoxylation reaction by: (a) preparing a catalyst suspension by: dissolving KOH as a basic catalyst in water as a solvent at room temperature, adding a first amount of NCEO with an adduct number of 1 to 3 (NCEO.sub.1-3) in an amount of 20 wt % to 50 wt % of the basic catalyst of the catalyst suspension, wherein the final mass concentration of the basic catalyst is 15 wt % to 25 wt % of the catalyst suspension, and stirring the catalyst suspension with sufficient intensity to evenly disperse the first amount of NCEO.sub.1-3 in the catalyst suspension, wherein: the NCEO.sub.1-3 has a structural formula shown in Formula II as follows: ##STR00005## Formula II, R is a straight-chain or branched alkyl group having a carbon number of C.sub.6-C.sub.15, n is 1 to 3, and the catalyst suspension optionally further comprises at least one of LiOH, K.sub.2CO.sub.3, or Na.sub.2CO.sub.3: (b) placing the catalyst suspension into a reactor, (c) adding a second amount of NCEO.sub.1-3 into the reactor with the catalyst suspension, wherein a dry mass of the basic catalyst is 0.1% to 1.0% of a total mass of the NCEO.sub.1-3 in the ethoxylation reaction, (d) stirring and heating the reactor to a reaction temperature of 90? C. to 140? C., (e) dehydrating the reactor in a vacuum until a water content in the reactor is lower than 0.1%; (f) adding ethylene oxide (EO) to the reactor at a molar ratio of NCEO.sub.1-3: EO of 1:8 while maintaining a system pressure at 0.1 to 0.5 Mpa in the reactor, and maintaining constant reaction temperature, (g) stirring the reactor for 0.5 hour to 1 hour after the pressure in the reactor does not drop any more, (h) cooling the reactor to room temperature, (i) neutralizing the reaction mixture in the reactor by addition of acetic acid to pH 6.5 to 7, and (i) discharging the reactor thereby producing NCEO emulsifier.

2. The method of claim 1, wherein the catalyst suspension is a disperse system comprising the NCEO.sub.1-3 and the basic catalyst.

3. The method of claim 1, wherein the catalyst suspension further comprises one or more of LiOH, K.sub.2CO.sub.3, and Na.sub.2CO.sub.3.

4. The method of claim 1, wherein adding ethylene oxide (EO) to the reactor is performed at 120? C. to 125? C.

5. The method of claim 1, wherein the NCEO produced comprises a polyethylene glycol content of 1.1% or less and an ethylene oxide residual of 7.2 ppm or less.

6. The method of claim 1, wherein the method further comprises adding the NCEO emulsifier to an oil phase to prepare an emulsion.

7. The method of claim 6, wherein the oil phase comprises one or more of liquid paraffin, biodiesel, xylene, olive oil, and dimethyl silicone oil.

8. The method of claim 6, wherein the NCEO emulsifier is added in an amount of 0.1% to the oil phase.

9. The method of claim 6, wherein the emulsion comprises no nonyl phenol.

Description

BRIEF DESCRIPTION OF FIGURES

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

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

(3) 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

(4) 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.

(5) 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).

(6) 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.

(7) 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

(8) 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.

(9) 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

(10) 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.

(11) 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

(12) 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

(13) 6 g of KOH was dissolved in 15 mL of water at room temperature to be stirred to obtain the KOH catalyst aqueous solution.

(14) 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

(15) 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.

(16) 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

(17) 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.

(18) 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

(19) 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.

(20) 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.

(21) 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.

(22) 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.

(23) 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

(24) 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.

(25) 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.

(26) 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

(27) 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.

(28) 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.