CN110078163B

CN110078163B - Application of polylysine derivative as demulsifier

Info

Publication number: CN110078163B
Application number: CN201910360749.XA
Authority: CN
Inventors: 张魏肖; 王天宇; 宁朋歌; 曹宏斌; 姜建壮
Original assignee: Institute of Process Engineering of CAS; University of Science and Technology Beijing USTB
Current assignee: Institute of Process Engineering of CAS; University of Science and Technology Beijing USTB
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-10-23
Anticipated expiration: 2039-04-30
Also published as: CN110078163A

Abstract

The invention provides an application of polylysine derivative as a demulsifier, relates to the technical field of wastewater treatment, and can obtain a novel demulsifier with low cost and no pollution, reduce the demulsification cost and protect the environment; the application is wide, and the method is suitable for demulsification treatment of various waste water; the polylysine derivative used as the demulsifier is a product obtained by substituting part of amino groups in polylysine with alkyl; the alkyl is dodecane, heptane and/or octane; the molar ratio of the polylysine main chain of the polylysine derivative to the alkyl is 1: 10-1: 30. The technical scheme provided by the invention is suitable for the demulsification process in various wastewater treatment processes.

Description

Application of polylysine derivative as demulsifier

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of wastewater treatment, in particular to application of a polylysine derivative as a demulsifier.

[ background of the invention ]

For the treatment of wastewater of steel enterprises, the treatment of emulsion is one of the key and difficult points, and demulsification is a very critical link. The emulsion in the steel industry has important characteristics. For example, the emulsion in cold rolling mill is generally oil-in-water emulsion, the oil content can reach about 8% by mass, and the organic matter concentration is very high. The efficient demulsification of the emulsion is an important problem to be solved urgently. On the other hand, the water, inorganic salts and organic substances in the crude oil emulsion have a great influence on the processes of crude oil extraction, transportation, storage and refining. Oilfield sewage also exists in the form of various emulsions. Demulsification associated with crude oil recovery is even more of a great need.

Although various emulsion breaking methods exist, the chemical emulsion breaking method based on the emulsion breaker is always most convenient and efficient, and the research and development of the novel emulsion breaker have very important significance. The demulsifiers are of various types, including ionic surfactants, nonionic polyether demulsifiers, polyamide demulsifiers, and the like. Among them, the polyamide demulsifiers gradually show great advantages and are more and more widely regarded by people.

Polylysine (-PL), a homotypic monomer polymer composed of many L-lysines, is produced by microbial fermentation and is a natural product with a polyamide structure. Polylysine has been widely developed for use in preservation, sterilization, drug carriers, and superabsorbent polymers, among others. In recent years, the synthesis of various derivatives of polylysine has attracted considerable research interest.

Accordingly, there is a need to find a low cost demulsifier from natural products to address the deficiencies of existing demulsifiers to solve or mitigate one or more of the problems described above.

[ summary of the invention ]

In view of the above, the invention provides an application of polylysine derivative as a demulsifier, which can obtain a novel demulsifier with low cost and no pollution, reduce the demulsification cost and protect the environment; and the application is wide, and the method is suitable for demulsification treatment of various waste waters.

On one hand, the invention provides application of a polylysine derivative as a demulsifier, which is characterized in that the polylysine derivative is a product obtained by replacing part of amino groups in polylysine with alkyl groups.

The above aspects and any possible implementations further provide an implementation in which the alkyl is dodecane, heptane, and/or octane.

The aspect as described above and any one possible implementation manner further provides an implementation manner in which the polylysine derivative has a polylysine main chain to the alkyl group molar ratio of 1:10 to 1: 30.

The above aspects and any possible implementation manner further provide an implementation manner, when the polylysine derivative is used as a demulsifying agent to perform demulsification, the temperature of demulsification is 30-60 ℃, the demulsification time is 30 minutes-1 hour, and the concentration of the polylysine derivative is 80 mg/L-3000 mg/L.

The above aspects and any possible implementations further provide an implementation in which the polylysine derivative is used as a demulsifier for demulsifying steel-making wastewater, metallurgical wastewater, oil-in-water crude oil emulsion, oil field wastewater, and petrochemical plant wastewater.

The above aspects and any possible implementation manners further provide an implementation manner that when the polylysine derivative is used for demulsifying the steelmaking wastewater, the demulsification rate is increased along with the increase of the concentration of the polylysine derivative in a concentration range of 0-200 mg/L.

The above aspects and any possible implementation manners further provide an implementation manner that the concentration of the polylysine derivative is 150mg/L, and the demulsification rate of the steelmaking wastewater reaches more than 80%.

The above aspects and any possible implementations further provide an implementation where the polylysine derivative is at a concentration of 600mg/L to 1000mg/L when the oil-in-water crude oil emulsion is broken.

The aspects as described above and in any possible implementation manner, there is further provided an implementation manner in which the chemical oxygen demand is gradually reduced with an increase in the concentration of the polylysine derivative in a concentration range of 0 to 300 mg/L.

In accordance with the above aspect and any possible implementation manner, there is further provided an implementation manner in which a heptane-substituted polylysine derivative is prepared by: s1, dissolving polylysine in dimethyl sulfoxide; s2, dropwise adding an alkaline solution into the solution obtained in the step S1, and stirring at a proper temperature; s3, adding bromoheptane into the stirred solution, and stirring at a proper temperature; s4, purifying and drying the product obtained in the S3 to obtain the heptane-substituted polylysine derivative.

Compared with the prior art, the invention can obtain the following technical effects: both polylysine derivatives and their degradation products are derived from natural products and are environmentally friendly; the demulsifier has wide applicability, and can be used for wastewater treatment of steel metallurgy enterprises and petroleum enterprises; the demulsifier can be prepared in large batch by low-cost raw materials and a simple synthesis method; the cost is low.

Of course, it is not necessary for any one product in which the invention is practiced to achieve all of the above-described technical effects simultaneously.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1A) is a NMR chart of dodecane substituted polylysine (-PL-g-dodecyl) provided by an embodiment of the present invention;

FIG. 1B) is an infrared spectrum of dodecane substituted polylysine (-PL-g-dodecyl) provided in accordance with an embodiment of the present invention;

FIG. 2 is a diagram of demulsification of a steel mill coking wastewater sample with demulsifiers of different concentrations provided by an embodiment of the present invention;

FIG. 3 is a graph showing the relationship between the concentration of a demulsifier and the demulsification rate when demulsifying the coking wastewater of a steel mill according to an embodiment of the present invention;

FIG. 4 is a graph of demulsifier dosage versus demulsification rate for demulsification of an oil-in-water crude oil emulsion sample according to one embodiment of the present invention;

FIG. 5 is a graph of demulsifier concentration versus chemical oxygen demand provided by one embodiment of the present invention.

[ detailed description ] embodiments

For better understanding of the technical solutions of the present invention, the following detailed descriptions of the embodiments of the present invention are provided with reference to the accompanying drawings.

It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The application of polylysine derivative as demulsifier, wherein the polylysine derivative (-PL-R) is a product obtained by alkylating part of amino groups in polylysine (-PL) which is natural product, and has main chain structure of polyamide; the terminal group comprises amino, hydrophobic alkyl chain and carboxylic acid; since the protonation of the amino group in water makes it positively charged, the free amino group in the demulsifier has a large positive charge in water. The element is L-lysine, so that the L-lysine also has a large number of homochiral centers, and the L-lysine can effectively promote water-oil separation. The polylysine derivative may have a molecular weight of from 5000 to 30000. Wherein the molar ratio of the polylysine main chain to the alkyl is 1: 10-1: 30. The alkyl related to the substitution can be dodecane, heptane and/or octane, and can also be other alkyl, and the polylysine substituted by partial alkyl can effectively reduce the interfacial tension and promote the oil-water separation of the emulsion. The formula is the structural formula of the partially alkyl substituted polylysine:

partial alkyl substitution improves the amphiphilicity of polylysine. And the rich cation of the polylysine derivative enables the polylysine derivative to have the characteristics of both the polyamide compound and the cationic surfactant. The natural product characteristics, wide sources, low price and simple structure modification of the polylysine make the derivative of the polylysine possibly become the demulsifier which is very environment-friendly, low in cost and wide in application.

The polylysine derivative may be dispersed in an oil-in-water emulsion for breaking. When the polylysine derivative is used as a demulsifying agent for demulsifying, the demulsifying temperature is 30-60 ℃, and the demulsifying time is 30 minutes-1 hour; the demulsification concentration of the polylysine derivative is 80-3000 mg/L. The polylysine derivative can be used as a demulsifier for demulsifying steel-making waste water, metallurgical waste water containing heavy metals, oil-in-water type crude oil emulsion, oil field sewage, waste water of petrochemical plants and the like. The various types of wastewater and sewage herein are generally oil-in-water type wastewater and sewage.

Example one: preparation of part heptane substituted polylysine demulsifier

Preparing a first step: 0.5g of polylysine (-PL) was dissolved in dimethyl sulfoxide (DMSO) in a round-bottomed flask, and 4ml of a 1mol/ml NaOH solution was added dropwise thereto, followed by stirring at 50 ℃ for 2 hours. Then, 10ml of dioxane solution containing 1.32g of bromoheptane was added thereto, and the mixture was stirred at 60 ℃ for 24 hours. And (3) purifying the product, namely putting the product into a dialysis bag, soaking the product in distilled water for dialysis for 3 days, and removing water and drying to obtain the product, namely the part of the heptane-substituted polylysine (-PL-g-heptanyl).

Preparing a second step: polylysine (2g) was dissolved in 30ml dimethyl sulfoxide (DMSO) and 10ml of a 1M NaOH solution was added dropwise with stirring at 50 ℃ and the system was stirred at 50 ℃ for 3 hours. Then a certain amount of dioxane solution of brominated alkanes is added dropwise, and the heating and stirring are continued for 24 hours. The product is purified by dialysis method, using semipermeable membrane to dialyze in pure water for about 3 days, removing water and drying to obtain polylysine derivative (-PL-R).

The NaOH solution is not the only reaction solution, but may be other alkaline solutions.

Preparation of polylysine derivatives may also be reacted with polylysine and alkyl bromide to give partially alkyl-substituted polylysine derivatives (-PL-R).

The preparation method of polylysine derivatives based on dodecane and octane substitution is substantially the same as the preparation method of polylysine derivatives substituted with heptane, and is not described herein in detail.

Example two: nuclear magnetic and infrared spectral characterization of partially dodecane substituted polylysine (-PL-g-dodecyl)

FIG. 1A) and FIG. 1B) are respectively a nuclear magnetic resonance image and an infrared spectrum of dodecane-substituted polylysine (-PL-g-dodecyl), from which analysis can be made: specificity of polylysine¹H-NMR peaks appeared between 1.2 and 4.0 ppm. Terminal methane and methylene groups corresponding to substituted alkyl chains at chemical shifts of about 3.12 and 3.32 ppm. in-PL-g-dodecyl, the peak at 0.82ppm is attributed to the methyl proton (-NH [ CH)₂-(CH₂)₁₀-CH₃]). While chemical shifts of 1.1-2.0ppm are attributed to the methylene hydrogen (-NH. CH) of the alkyl group attached to N₂-(CH₂)₁₀-CH₃]) And (4) reacting. The peak around 2900cm-1, which can be found by analysis in the infrared spectrum, is C-H tensile vibration, and a wide absorption band in the range of 3200 to 3300cm-1 is attributed to N-H stretching vibration.

Example three: demulsification of coking wastewater sample of Hebei iron and steel group Handan iron and steel company

Taking the Handrail waste water sample into 10 centrifugal tubes with 10ml, and exploring the influence of different amounts of the demulsifier on the demulsification effect. The same Handrail sewage emulsion was measured in 10ml centrifuge tubes, and the volume of addition was 5 ml. Preparing 50ml of demulsifier with the concentration of 1000mg/L, extracting the demulsifier by using a 1ml needle tube, and adding 0.1ml, 0.2ml, 0.3ml, 0.4ml, 0.5ml, 0.6ml, 0.7ml, 0.8ml, 0.9ml and 1ml of demulsifier into the sample of the Handover sewage emulsion. Water bath is 50-55 deg.c and demulsifying time is 1 hr. The system is kept stand, the demulsification phenomenon is observed, and as can be seen from figure 2, the synthesized partially alkyl-substituted polylysine (-PL-g-dodecyl) has good demulsification effect on the Handover sewage. As can be seen from FIG. 3, the demulsification rate can reach more than 80% under the condition of 150 mg/L. From the figure 3, it can be seen that within a certain demulsification dosage range, the demulsification effect is better along with the increase of the demulsification dosage.

Example four: demulsification of oil-in-water type crude oil emulsion sample

Preparing a demulsifier with the concentration of 10g/L, preparing 6 separating funnels, measuring 5ml of crude oil emulsion sample respectively, controlling other conditions to be unchanged, wherein the demulsification temperature is 50 ℃ and the demulsification time is 30 min. The amounts of the demulsifier solution added were: 50ul, 100ul, 200ul, 300ul, 400ul and 500ul are heated in a water bath of a shaking table for 30min, then 25ml of carbon tetrachloride serving as an extractant is added, then the shaking table is used for extraction for 20min, the mixture is kept stand for 10min, then the oil-water separation condition is studied by measuring the oil content, and the demulsification results are shown in table 1 and figure 4. For the oil-in-water type crude oil emulsion sample, the demulsifying effect is better when the concentration of the demulsifier is 600-1000 mg/L; at a concentration of 800mg/L, the best demulsification effect can be achieved, namely, the demulsification rate is about 35 percent.

TABLE 1

Example five: determination of Chemical Oxygen Demand (COD)

And (3) opening a switch of the COD instrument to heat the machine to 165 ℃, taking a sample of 2.5ml, adding a standard amount of D-reagent and C-reagent into the digestion tube, uniformly vibrating, putting the digestion tube into the COD instrument, clicking a digestion button, and clicking to close after digestion is finished. Next, the digestion tube was cooled to room temperature, 2.5ml of distilled water was added to the digestion tube, and the mixture was allowed to stand for 8 to 10 min. And opening the COD instrument again, starting measurement, firstly measuring the COD of the distilled water, aiming at measuring a blank sample, clicking the blank after the blank measurement is finished, and then sequentially measuring the samples. The data are recorded as in table 2. From Table 2, it can be seen that the effect of the addition of the demulsifier-PL-R on COD is significant, and the specific linear relationship is shown in FIG. 5, and the chemical oxygen demand of the demulsifier gradually decreases with the increase of the concentration of the demulsifier. COD is an important and relatively fast measurable parameter of organic contamination, and emulsion is often accompanied by a large amount of organic matter, and the reduction of COD can indicate the degradation of organic matter by the demulsifier. Thus, the gradual decrease in chemical oxygen demand in FIG. 5 indicates a significant decrease in the level of organic contamination in the water.

TABLE 2

Concentration of demulsifier added/mg/L	Oxygen demand/mg/L
		0	304.0
100	252.8
		200	243.9
300	222.7

Compared with the prior art, the invention has the beneficial effects that: (a) both polylysine derivatives and their degradation products are derived from natural products and are environmentally friendly; (b) the demulsifier has wider applicability, and can be used for wastewater treatment of ferrous metallurgy enterprises and petroleum enterprises; (c) the demulsifier can be prepared in large batch by low-cost raw materials and a simple synthesis method; (d) the demulsifier of the invention integrates the characteristics of a polyamide demulsifier and a cationic demulsifier, and has the advantages of high branching, good dispersibility, mild reaction conditions and the like; (e) the molecules of the demulsifier of the invention have a large number of homochiral centers, and the molecular chirality is beneficial to phase separation, aggregation and flocculation in the demulsification process; (f) the polylysine derivative can stably exist in a high-temperature environment, and the application range of the demulsifier is further expanded.

The application of the polylysine derivative as the demulsifier provided by the embodiments of the present application is described in detail above. The above description of the embodiments is only for the purpose of helping to understand the method of the present application and its core ideas; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

As used in the specification and claims, certain terms are used to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect. The description which follows is a preferred embodiment of the present application, but is made for the purpose of illustrating the general principles of the application and not for the purpose of limiting the scope of the application. The protection scope of the present application shall be subject to the definitions of the appended claims.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The foregoing description shows and describes several preferred embodiments of the present application, but as aforementioned, it is to be understood that the application is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the application as described herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the application, which is to be protected by the claims appended hereto.

Claims

1. The application of the polylysine derivative as the demulsifier is characterized in that the polylysine derivative is a product obtained by alkyl substitution of part of amino groups in polylysine;

the structural formula of the product obtained after part of amino groups in the polylysine are substituted by alkyl is as follows:

2. use of polylysine derivatives according to claim 1 as demulsifiers, wherein the alkyl groups are dodecane, heptane and/or octane.

3. The use of a polylysine derivative according to claim 1 or 2 as a demulsifier, wherein the polylysine derivative has a polylysine backbone to alkyl group molar ratio of from 1:10 to 1: 30.

4. The use of the polylysine derivative as a demulsifier according to claim 3, wherein the polylysine derivative is used as a demulsifier to demulsify at a temperature of 30-60 ℃ for 30 minutes-1 hour, and the polylysine derivative has a concentration of 80-3000 mg/L.

5. The use of a polylysine derivative as a demulsifier according to claim 4, wherein the polylysine derivative is used as a demulsifier for demulsifying steel-making wastewater, metallurgical wastewater, oil-in-water crude oil emulsion, oil field wastewater, and petrochemical plant wastewater.

6. The use of polylysine derivative as a demulsifier according to claim 5, wherein the polylysine derivative demulsifies the steelmaking wastewater at a concentration ranging from 80 to 200mg/L, and the demulsification rate increases with increasing polylysine derivative concentration.

7. The use of the polylysine derivative as a demulsifier according to claim 6, wherein the concentration of the polylysine derivative is 150mg/L, the demulsification rate on the steelmaking wastewater is more than 80%.

8. The use of a polylysine derivative as a demulsifier according to claim 5, wherein the polylysine derivative is present at a concentration of from 600mg/L to 1000mg/L when demulsifying an oil-in-water crude oil emulsion.

9. The use of polylysine derivative as a demulsifier according to claim 5, wherein the chemical oxygen demand of the polylysine derivative decreases with increasing concentration in the range of 80-300 mg/L.

10. The use of polylysine derivative as claimed in claim 2, wherein the heptane-substituted polylysine derivative is prepared by: s1, dissolving polylysine in dimethyl sulfoxide; s2, dropwise adding an alkaline solution into the solution obtained in the step S1, and stirring at a proper temperature; s3, adding bromoheptane into the stirred solution, and stirring at a proper temperature; s4, purifying and drying the product obtained in the S3 to obtain the heptane-substituted polylysine derivative.