Biological oil spill dispersant and preparation method thereof

Abstract

The invention discloses a biological type oil spill dispersing agent and a preparation method thereof, and the method comprises the following steps: selecting a natural anionic surfactant and a nonionic surfactant, mixing the natural anionic surfactant and the nonionic surfactant with a solvent and an auxiliary agent, then adding petroleum degrading bacteria in proportion, and mixing to obtain the biological type green and efficient oil spill dispersing agent. According to the invention, the oil spill dispersing agent is combined with petroleum degrading bacteria, the 30 s emulsification rate of the prepared oil spill dispersing agent reaches 69.28%, other indexes all exceed the requirements of the national standard GB18188.1-2000, the 7 d degradation rate of crude oil is 87.62%, and the oil spill dispersing agent can emulsify and disperse oil spill on the water surface and also has the effect of degrading and eliminating petroleum pollutants.

Description

Technical Field

[0001] The present invention relates to the technical field of biological emulsification and degradation for treating marine oil spills (water pollution prevention and control), and particularly relates to a biological oil spill dispersant and a preparation method thereof. Background Art

[0002] With the booming development of the shipping industry, a large amount of oily bilge water is generated during the operation of ships, and even oil spills occur. According to incomplete statistics, about 300,000 tons of oily bilge water and 2 - 10 million tons of oil are poured into the ocean every year, which will inevitably have an adverse impact on the marine ecological environment. For dealing with sudden marine oil spills, oil spill dispersants are an effective option.

[0003] An oil spill dispersant is composed of high - purity surfactants, coupling agents, penetrants and water. It has good effects of penetrating, diluting and viscosity - reducing on the polluted oil. After the content of the emulsifier is optimized and balanced, it has excellent emulsifying and dispersing ability, so as to efficiently emulsify the polluted oil and disperse it into the water body. After being sprayed on the polluted oil, it first penetrates into the polluted oil and fuses with it, and then undergoes an emulsification reaction with water under mechanical agitation or natural agitation of water waves, forming an oil - in - water emulsion and dispersing in the water body. Due to the increased surface area, the oil - contaminated particles can fully contact microorganisms and be degraded by them as soon as possible. Since most surfactants are chemical - based and pose a risk of secondary pollution to the environment, therefore, researching and preparing more green, safe and efficient oil spill dispersants has become a current research hotspot.

[0004] Currently, research is being carried out in this regard. For example, in the publication number CN111534281A "An Environment - Friendly Oil Spill Dispersant and a Preparation Method Thereof", the oil spill dispersant prepared with non - ionic and anionic biosurfactants as the main components not only improves its biodegradability but also reduces its biological toxicity; in the publication number CN115895685A "A Preparation Method of a Highly Efficient Marine Oil Spill Dispersant Based on a Gemini Surfactant Composite System", the dispersant prepared by compounding biosurfactants, Gemini surfactants and ethylene glycol monobutyl ether (or dipropylene glycol monobutyl ether) has high stability and low biological toxicity; in the publication number CN111732937A "A Foaming Degradable Oil Spill Dispersant on the Water Surface and a Preparation Method Thereof", the dispersant obtained by compounding biosurfactants such as fatty alcohol polyoxyethylene ether and glycolipid has good dispersing effect and low pollution. None of the above - mentioned dispersants can better balance the improvement of the dispersion rate while reducing its biological toxicity, and they only have the function of emulsifying and dispersing oil spills on the water surface and cannot degrade and eliminate them. Therefore, it is necessary to develop a highly efficient, economical and environment - friendly oil spill dispersant, which has certain practical significance for solving the application bottleneck of oil spill dispersants in oil spill accidents. Summary of the Invention

[0005] To solve the problems of poor dispersion effect and high biological toxicity of traditional oil spill dispersants, the present invention provides a biological oil spill dispersant and its preparation method, which can be applied to the in-situ treatment of oil spills on the water surface. The oil spill dispersant obtained by the preparation method of the present invention can be applied to various environments, can emulsify and disperse oil stains, is green and environmentally friendly, and will not cause secondary pollution to the environment.

[0006] On the one hand, the present application provides a biological oil spill dispersant, and the dispersant contains sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, polyethylene glycol, ethanol, purified water, ethylene glycol, alkyl polyglycoside, and petroleum hydrocarbon degrading bacteria.

[0007] Further, in terms of weight percentage, the dispersant contains 6-12 wt% of sodium dodecylbenzenesulfonate, 4-12 wt% of rhamnolipid, 6-11 wt% of fatty alcohol polyoxyethylene ether, 3-4 wt% of polyethylene glycol, 10-13 wt% of ethanol, 2-2.5 wt% of ethylene glycol, 2-5 wt% of alkyl polyglycoside, and a bacterial suspension of petroleum hydrocarbon degrading bacteria 1×10 14 ~1×10 20 CFU / mL, and the balance is water.

[0008] Further, the petroleum degrading bacteria are one or more of the genera Rhodopseudomonas palustris, Pacific alkanovores, Bacillus toyonensis, Bacillus albus, and Proteus vulgaris;

[0009] Further, the concentration of the bacterial suspension in the dispersion liquid is 1×10 15 ~1×10 18 CFU / mL; preferably 1×10 16 ~1×10 17 CFU / mL.

[0010] On the other hand, the present application provides a preparation method of a biological oil spill dispersant. The characteristics of the present invention include the following steps:

[0011] (1) Weigh sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, polyethylene glycol, ethanol, purified water, ethylene glycol, and alkyl polyglycoside by weight for standby;

[0012] (2) Stir, heat, and mix evenly the weighed sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl polyglycoside, and then cool;

[0013] (3) Mix the mixture obtained in step (2) with the remaining 50% polyethylene glycol, 50% ethanol, 50% purified water, and 50% ethylene glycol evenly to obtain a dispersant.

[0014] (4) Add petroleum hydrocarbon-degrading bacteria to the dispersant obtained in step (3) to obtain a biological oil spill dispersant.

[0015] Further, in step (2), stir and heat to 40 - 60 °C and stir for 20 - 30 min.

[0016] Further, in step (1), the mass content of the anionic surfactant is 10 - 22 wt%; the mass content of the non-ionic surfactant is 8 - 16 wt%.

[0017] Further, the purpose of mixing the solvent, auxiliary agent, and surfactant step by step in step (3) is to make the mixing more uniform.

[0018] Further, the petroleum-degrading bacteria in step (4) are an independently constructed mixed bacterial community, including but not limited to one or more of the genera Rhodopseudomonas palustris, Pacific alkanovores, Bacillus toyonensis, Bacillus albus, and Proteus vulgaris.

[0019] Further, in actual application, the volume ratio of the bacterial liquid to the dispersant is 1:9 - 9:1.

[0020] The solvent in the present invention is purified water or ethanol; the auxiliary agent is polyethylene glycol or ethylene glycol; the surfactant is divided into an anionic surfactant and a non-ionic surfactant. The anionic surfactant is sodium dodecylbenzenesulfonate and rhamnolipid, and the non-ionic surfactant is fatty alcohol polyoxyethylene ether and alkyl glycoside.

[0021] A biological oil spill dispersant is prepared by the above method.

[0022] Compared with the prior art, the present invention has the following remarkable advantages:

[0023] (1) For the oil spill dispersant prepared in the present invention, its emulsification rate is measured according to the national standard "Technical Conditions for Oil Spill Dispersants" (GB18188.1 - 2000). The 30s emulsification rate of this dispersant can reach 69.28%, and the 10min emulsification rate can reach 35.83%, both higher than the national standard requirements, and it can be applied to the emergency treatment of oil spills on the water surface.

[0024] (2) The surfactant in the oil spill dispersant composition prepared by the present invention is a natural extract or low-toxic type, reducing the harm of chemical surfactants to fish (marine organisms). According to the detection of (GB18188.1-2000), its fish toxicity meets the requirement that the median lethal time for fish exceeds 24 hours, and no fish deaths were found during the test time. It is an environmentally friendly product.

[0025] (3) The kinematic viscosity of the oil spill dispersant prepared by the present invention is 28.39 mm 2 ·s -2 , the flash point is greater than 70 °C, and the appearance is a yellowish-brown transparent liquid without stratification.

[0026] (4) The biological oil spill dispersant prepared by the present invention has a high degradation rate for crude oil. The 7-day degradation rate for crude oil reaches 87.62%. While emulsifying the oil spill on the water surface, it realizes the degradation and elimination of oil pollutants.

[0027] (5) The emulsification rate of the biological oil spill dispersant prepared by the present invention has been significantly improved. Compared with the single use of sodium dodecylbenzenesulfonate and rhamnolipid, the 30s emulsification rate of the dispersant for crude oil is increased by 21.61% and 14.15% respectively. Brief Description of the Drawings

[0028] Figure 1 is the technical route diagram for preparing the biological oil spill dispersant of the present invention.

[0029] Figure 2 is the emulsification rate of the oil spill dispersant at different dispersant-to-oil ratios (DOR).

[0030] Figure 3 is the surface tension of the emulsion at different dispersant-to-oil ratios (DOR).

[0031] Figure 4 is the emulsification situation of the oil spill dispersant for crude oil at different dispersant-to-oil ratios (DOR).

[0032] Figure 5 is the growth curve of the dispersant for the microbial flora at different volume ratios.

[0033] Figure 6 is the 7-day degradation rate of the biological oil spill dispersant prepared by the present invention for crude oil. Detailed Embodiments

[0034] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the scope of protection of the present invention.

[0035] The screening experiment of the surfactant component of a biotype oil spill dispersant is as follows:

[0036] Anionic surfactants have good detergency, foaming, and emulsifying properties; cationic surfactants have strong bactericidal and disinfectant abilities and certain biological toxicity; nonionic surfactants have good emulsifying, wetting, and dispersing properties. To meet the characteristics of green environmental protection and no secondary pollution of the present invention, anionic surfactants and nonionic surfactants are selected for the surfactant of the present invention considering comprehensively.

[0037] Therefore, the platinum ring method and the emulsification index method are used to measure the surface tension and emulsification rate of each surfactant respectively, and the average value is taken after repeating 3 times. The results are shown in Table 1.

[0038] Table 1 Comparison of surfactant properties

[0039]

[0040] In summary, rhamnolipid and sodium dodecylbenzenesulfonate are selected as anionic surfactants, and fatty alcohol polyoxyethylene ether and alkyl polyglycoside are selected as nonionic surfactants.

[0041] The degradation bacteria used in the present invention are Rhodopseudomonas palustris, Pacific alkanovores, Bacillus toyonensis, Bacillus albus, and Proteus vulgaris, which are purchased from BeiNa Bio - Henan Engineering Technology Research Center for Industrial Microbial Strains.

[0042] Example 1

[0043] The specific operation for preparing a biotype oil spill dispersant is as follows:

[0044] (1) Weigh 11.21 wt% of sodium dodecylbenzenesulfonate, 8.97 wt% of fatty alcohol polyoxyethylene ether, 3.59 wt% of polyethylene glycol, 11.21 wt% of ethanol, 62.78 wt% of purified water, and 2.24 wt% of ethylene glycol for standby;

[0045] (2) Mix the weighed sodium dodecylbenzenesulfonate, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol evenly, stir and heat to 50 °C, stir for 25 min, and cool to room temperature;

[0046] (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol to obtain a dispersant;

[0047] (4) Add Rhodopseudomonas palustris and Pacificalkanovores (the viable cell number ratio of the two is 1:1) with a bacterial suspension concentration of 5×10 16 CFU / mL of petroleum hydrocarbon-degrading bacteria, and the volume ratio of the two is 9:1 to obtain a bio-based oil spill dispersant.

[0048] Example 2

[0049] The specific operation for preparing a bio-based oil spill dispersant is as follows:

[0050] (1) Weigh rhamnolipid 9.17 wt%, fatty alcohol polyoxyethylene ether 9.17 wt%, polyethylene glycol 3.67 wt%, ethanol 11.47 wt%, purified water 64.22 wt%, and ethylene glycol 2.29 wt% for standby;

[0051] (2) Mix the weighed rhamnolipid, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol evenly, stir and heat to 50 °C, stir for 25 min, and cool to room temperature;

[0052] (3) Mix the mixture obtained in step (2) with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol evenly to obtain a dispersant;

[0053] (4) Add Pacific alkanovores, Bacillus toyonensis, and Bacillus albu (the viable cell number ratio of the three is 1:1:1) with a bacterial suspension concentration of 5×10 16 CFU / mL of petroleum hydrocarbon-degrading bacteria, and the volume ratio of the two is 9:1 to obtain a bio-based oil spill dispersant.

[0054] Example 3

[0055] The specific operation for preparing a bio-based oil spill dispersant is as follows:

[0056] (1) Weigh sodium dodecylbenzenesulfonate 12.02 wt%, polyethylene glycol 3.85 wt%, ethanol 12.02 wt%, purified water 67.31 wt%, ethylene glycol 2.40 wt%, and alkyl polyglycoside 2.40 wt% for standby;

[0057] (2) Mix the weighed sodium dodecylbenzenesulfonate, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl polyglycoside evenly, stir and heat to 50 °C, stir for 25 min, and cool to room temperature;

[0058] (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol to obtain a dispersant;

[0059] (4) Add a petroleum hydrocarbon degrading bacterium with a bacterial suspension concentration of 5×10 16 CFU / mL of Rhodopseudomonas palustris, Bacillus albus, and Proteus vulgaris (the viable cell number ratio of the three is 1:1:1) to the dispersant obtained in step (3), and the volume ratio of the two is 9:1 to obtain a bio-based oil spill dispersant.

[0060] Example 4

[0061] The specific operation for preparing a bio-based oil spill dispersant is as follows:

[0062] (1) Weigh 10.08 wt% of sodium dodecylbenzenesulfonate, 8.06 wt% of rhamnolipid, 8.06 wt% of fatty alcohol polyoxyethylene ether, 3.23 wt% of polyethylene glycol, 10.08 wt% of ethanol, 56.45 wt% of purified water, 2.02 wt% of ethylene glycol, and 2.02 wt% of alkyl polyglycoside for standby;

[0063] (2) Mix the weighed sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether with 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl polyglycoside evenly, stir and heat to 50°C, stir for 25 min, and cool to room temperature;

[0064] (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol to obtain a dispersant;

[0065] (4) Add a petroleum hydrocarbon degrading bacterium with a bacterial suspension concentration of 7.6×1016 CFU / mL of Rhodopseudomonas palustris, Pacificalkanovores, Bacillus toyonensis, Bacillus albus, and Proteus vulgaris (the viable cell number ratio of the five bacteria is 1:1:1:1:1) to the dispersant obtained in step (3), and the volume ratio of the two is 9:1 to obtain a bio-based oil spill dispersant.

[0066] Example 5

[0067] The specific operation for preparing a bio-based oil spill dispersant is as follows:

[0068] (1) Weigh 8.23 wt% of sodium dodecylbenzenesulfonate, 6.17 wt% of rhamnolipid, 10.29 wt% of fatty alcohol polyoxyethylene ether, 3.29 wt% of polyethylene glycol, 10.29 wt% of ethanol, 57.61 wt% of purified water, and 4.12 wt% of alkyl polyglycoside for later use;

[0069] (2) Mix the weighed sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl polyglycoside evenly, stir and heat to 40 °C, stir for 20 min, and then cool to room temperature;

[0070] (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol to obtain a dispersant;

[0071] (4) Add a bacterial suspension of Bacillus toyonensis, Bacillus albus, and Proteus vulgaris (the viable cell number ratio of the three is 1:1:1) with a concentration of 6×10 16 CFU / mL of petroleum hydrocarbon-degrading bacteria to the dispersant obtained in step (3), and the volume ratio of the two is 8:2 to obtain a bio-based oil spill dispersant.

[0072] Example 6

[0073] The specific operation for preparing a bio-based oil spill dispersant is as follows:

[0074] (1) Weigh 6.82 wt% of sodium dodecylbenzenesulfonate, 4.55 wt% of rhamnolipid, 6.82 wt% of fatty alcohol polyoxyethylene ether, 11.36 wt% of ethanol, 63.64 wt% of purified water, 2.27 wt% of ethylene glycol, and 4.55 wt% of alkyl polyglycoside for later use;

[0075] (2) Mix the weighed sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl polyglycoside evenly, stir and heat to 60 °C, stir for 30 min, and then cool to room temperature;

[0076] (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, and 50% of ethylene glycol to obtain a dispersant;

[0077] (4) Add the petroleum hydrocarbon degrading bacteria with a concentration of 7×10 16 CFU / mL of Pacific alkanovores, Bacillus albus, and Proteus vulgaris (the viable bacteria count ratio of the three is 1:1:1) to the dispersant obtained in step (3), and the volume ratio of the two is 7:3 to obtain a bio-based oil spill dispersant.

[0078] According to the determination methods of emulsification rate, biodegradability, and biotoxicity of oil spill dispersants in the national standard "Guidelines for the Use of Oil Spill Dispersants" (GB18188.2-2000), at a DOR of 25%, the 30s and 10min emulsification rates of the prepared oil spill dispersant are 69.28% and 35.83% respectively, which are 15.47% and 79.15% higher than the specified values of the standard respectively; the biodegradability is increased by 55.13%; the half-lethal time of fish for biotoxicity evaluation exceeds 24h, and no fish deaths are found within the test time.

[0079] The dispersant and the bacterial community are compounded to obtain the best compounding ratio of 1:9; finally, the 7-day degradation rate of the bio-based green and highly efficient oil spill dispersant for crude oil is measured to be 87.62%. While emulsifying and dispersing the oil spill on the water surface, the degradation and elimination of pollutants are achieved.

[0080] Referring to the standard GB18188.1-2000, the performance indicators of the dispersant are measured, and the results are shown in Table 2.

[0081] Table 2 Specific performance indicators of the dispersant

[0082]

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail through the above embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the above embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A biotype oil spill dispersant, characterized in that, Comprising the following components: Sodium dodecylbenzenesulfonate 6 - 12 wt%, rhamnolipid 4 - 12 wt%, fatty alcohol polyoxyethylene ether 6 - 11 wt%, polyethylene glycol 3 - 4 wt%, ethanol 10 - 13 wt%, ethylene glycol 2 - 2.5 wt%, alkyl polyglycoside 2 - 5 wt%, petroleum hydrocarbon degrading bacteria suspension 1×10 14 ~1×10 20 CFU / mL。 2. The oil spill dispersant according to claim 1, characterized in that, The petroleum hydrocarbon-degrading bacteria are Rhodopseudomonas palustris, Pacific alkanovores, Bacillus toyonensis, Bacillus albus, Proteus vulgaris one or more species in the genus.

3. The oil spill dispersant according to claim 1, wherein The concentration of the bacterial suspension in the dispersant is 1×10 15 ~1×10 18 CFU / mL.

4. A preparation method of a biological oil spill dispersant according to claim 1, characterized in that, The preparation method comprises the following steps: (1) Weigh sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, polyethylene glycol, ethanol, water, ethylene glycol, and alkyl glycoside according to weight for standby; (2) Stir and heat the weighed sodium dodecylbenzenesulfonate, rhamnolipid, fatty alcohol polyoxyethylene ether, 50% of polyethylene glycol, 50% of ethanol, 50% of purified water, 50% of ethylene glycol, and alkyl glycoside until they are mixed evenly, and then cool; (3) Mix the mixture obtained in step (2) evenly with the remaining 50% of polyethylene glycol, 50% of ethanol, 50% of water, and 50% of ethylene glycol to obtain a dispersant; (4) Add a petroleum hydrocarbon degrading bacterium suspension to the dispersant obtained in step (3) to obtain a biological type green and highly efficient oil spill dispersant.

5. The preparation method according to claim 4, characterized in that, In step (2), it is stirred and heated to 40 - 60 °C and stirred for 20 - 30 min.

6. Use of a biotype oil spill dispersant according to claim 1, characterized in that, The oil spill dispersant is used for the treatment of oil pollutants.

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