JPH0334517B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to additives that improve the fluidity of crude oil. More specifically, it relates to an additive that improves the fluidity of crude oil at low temperatures. At low temperatures, crude oil loses its fluidity due to the precipitation of paraffin wax contained therein, making it impossible to transport or making it difficult to burn in a burner. BACKGROUND ART Fluidity improving additives have been conventionally added to petroleum-based fuel oils in order to maintain fluidity even at low temperatures. Many additive components used for this purpose include polyalkyl (meth)acrylates, condensates of chlorinated paraffins and naphthalene, alkenyl succinic acid amides, and ethylene-vinyl acetate copolymers.
However, most of these do not often exhibit a satisfactory pour point lowering effect on crude oil. The present inventor has conducted intensive research to develop a fluidity-improving additive that exhibits an excellent fluidity-lowering effect on crude oil. The present invention was achieved by discovering that a polymer significantly improves the fluidity of crude oil. That is, the present invention provides (meth)acrylate (a) of an aliphatic alcohol (having 12 or more carbon atoms) and an alkylene oxide adduct of the aliphatic alcohol (meth)acrylate (a).
This is a crude oil fluidity improving additive characterized by containing a copolymer with acrylate (b). In the (meth)acrylate of an aliphatic alcohol having 12 or more carbon atoms, the aliphatic alcohol includes saturated or unsaturated linear or branched alcohols such as lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, oleyl alcohol, Eicosyl alcohol, docosyl alcohol, tetracosyl alcohol, aliphatic alcohols with a wide carbon chain distribution derived from natural animal and vegetable oils, straight chain synthetic alcohols such as Ziegler process synthetic alcohol [Alfur (manufactured by Continental Oil)] ]; Branched synthetic alcohols {for example, oxo-method alcohols [Dovanol (manufactured by Ciel Chemical), Oxocol (manufactured by Nissan Chemical), Diadol (manufactured by Mitsubishi Kasei), secondary alcohols obtained by oxidation of paraffin [Lyall (manufactured by Liqui Chemical) (manufactured by Union Carbide), Tergitol S (manufactured by Union Carbide), and two or more of these alcohols. Among these, preferred are linear aliphatic saturated alcohols having a carbon number of 16 to 30. If there is no aliphatic alcohol with a carbon number of 12 or more, the pour point lowering effect will be insufficient. Chain or branched saturated or unsaturated aliphatic alcohols such as methyl alcohol, butyl alcohol, hexyl alcohol, 2-ethylhexyl alcohol,
Examples include octyl alcohol, decyl alcohol, dodecyl alcohol, the aforementioned alcohols having 12 or more carbon atoms, and mixtures of two or more of these. Among these, preferred are aliphatic alcohols having 6 to 40 carbon atoms. In addition, alkylene oxides include ethylene oxide, propylene oxide, butylene oxide,
(1.2-, 2.3-, 1.4-butylene oxide, etc.), styrene oxide, epichlorohydrin, and two or more thereof, preferably ethylene oxide, propylene oxide, and a combination thereof. In the alkylene oxide adduct of aliphatic alcohol, the number of moles of alkylene oxide added to the aliphatic alcohol is usually in the range of 1 to 70 moles, preferably in the range of 5 to 50 moles. When the number of moles of alkylene oxide added exceeds 70, the solubility in crude oil decreases. Examples of the form in which two or more alkylene oxides are added to an aliphatic alcohol include those in which they are added randomly or in the form of blocks. The copolymer of the present invention may contain other monomers in addition to (a) and (b), and other monomers include lipophilic monomers such as monoethylene monomers (ethylene , propylene, butylene, etc.), aromatic hydrocarbon monomers (styrenes such as styrene, α-alkylstyrene, etc.), unsaturated alcohol esters of higher fatty acids (higher fatty acids with 10 or more carbon atoms, such as capric acid, myristic acid, vinyl esters or allyl esters such as stearic acid), hydrophilic or weakly hydrophilic monomers such as acyclic amines [dialkylaminoalkyl (meth)
Acrylates such as dimethylaminoethyl (meth)acrylate], cyclic amines [pyridine,
N-(meth)acryloyloxyalkylmorpholine, e.g. N-methacryloyloxyethylmorpholine, N-(meth)acryloylpolyoxyalkylmorpholine, e.g. N-methacryloylpentaoxyethylmorpholine] Acyclic amide ((meth)acrylamide etc.), cyclic Examples include amides (vinyl lactams, such as vinyl pyrrolidone), imides (maleic acid imide, etc.), nitriles [(meth)acrylonitrile, etc.], and quaternary nitrogen-containing monomers [such as quaternized products of the above-mentioned acyclic amines or cyclic amines]. . The molar ratio of (a) and (b) in the copolymer of (a) and (b) can be freely changed, but is usually 1:0.03 to 1:10, preferably 1:0.1 to 1. :5. When (b) is less than 0.03, there is no synergistic effect due to copolymerization and the pour point lowering effect is insufficient, and when (b) is greater than 10, the solubility in crude oil decreases. The total content of (a) and (b) in all monomers is usually 80 mol% or more, preferably 85 to 100 mol%. The copolymer can be produced in the same way as in the case of copolymerization of general acrylic esters or methacrylic esters. in the presence or absence of an inert solvent for the reaction system, such as aromatic hydrocarbon solvents (e.g. can be easily produced by heating normally to 60°C to 140°C in an inert gas atmosphere. The number average molecular weight of the copolymer in the present invention is usually
The range is from 3,000 to 100,000, preferably from 10,000 to 50,000. If the number average molecular weight is outside this range (3,000 to 100,000), the pour point lowering effect and the solubility in crude oil will be insufficient. The properties of the copolymer in the present invention and its solubility in petroleum solvents including crude oil are determined by (a) the length and structure of the aliphatic group of the component, (b) the type of aliphatic alcohol of the component, the type of alkylene oxide, and the addition mole. Although the number varies depending on the ratio of components (a) and (b) and the molecular weight of the copolymer, it is usually solid or viscous liquid. Regarding solubility in crude oil and petroleum-based solvents, it shows good solubility even when these factors are varied within a fairly large range. Crude oil to which the additive of the present invention can be applied includes the United States, Venezuela, the Middle East (Iran, Iraq, Saudi Arabia, Kuwait), Canada, and Southeast Asia (Indonesia, Brunei, etc.)
Crude oil is produced in China, Mexico, the Soviet Union, Romania, the North Sea region, etc., and its properties vary depending on the region of production, but the main component is a mixture of various hydrocarbons with carbon numbers of 4 to 40. It usually also contains small amounts of sulfur, nitrogen, and metals. One of the major factors governing the fluidity of such crude oil at low temperatures is the molecular weight and content of linear paraffin contained in the crude oil. For example, Middle Eastern crude oil such as Arabian Light The content of linear paraffin is relatively low, and the carbon number of linear paraffin is also low, so it has good fluidity at low temperatures. However, some crude oil produced from Southeast Asia and China has a low carbon number. Many of them contain large amounts of large linear paraffins, and therefore have poor fluidity at low temperatures. The additive of the present invention can be applied to crude oils with a low content of linear paraffins, such as Middle Eastern crude oils, as well as linear paraffins with a high melting point and a large number of carbon atoms, such as Southeast Asian crude oils and Chinese crude oils (for example, melting points of 38° to 38°C). It can also be used for crude oil containing a large amount of 76℃, carbon number 20-36, and a large amount of wax (sometimes referred to as wax). It is particularly suitable for crude oil with a high wax content. The wax content in crude oil usually varies between 2 and 30% by weight, and its pour point (lowest temperature at which it can flow) is, for example, -
The pour point ranges over a wide range of 35°C to 40°C, but in the case of crude oil with a high wax content such as Chinese crude oil, the pour point reaches a range of 20°C to 40°C. When using the additive of the present invention, the content is usually 0.001 to 1.0 on a weight basis in crude oil.
%, preferably 0.01 to 0.3%, and the method of incorporating it into crude oil is not particularly limited. Examples include a method in which the additive is added to crude oil as it is, a method in which the fluidity improver is diluted with a solvent such as an aromatic hydrocarbon solvent, kerosene, light oil, A heavy oil, etc., and then added. Conventionally, there has been a major problem that conventional fluidity-improving additives are not sufficiently effective for crude oil with a high pour point, but the additive of the present invention has a significant effect even when added at a very low concentration. This is an epoch-making product that shows the effect of improving fluidity. Furthermore, the effect of the additive of the present invention is not only to lower the pour point, but also to significantly lower the viscosity of the added crude oil at temperatures above the pour point. These effects can be achieved by eliminating the need for heating and significantly improving transportation efficiency by reducing viscosity, whereas conventional pipeline transportation required heating, which required a huge amount of expense. There are great economic benefits. The present invention will be further explained below with reference to Examples, Comparative Examples, and Test Examples, but the present invention is not limited thereto. Example 1 An additive of the present invention was produced as follows. In a 1 liter glass four-necked flask equipped with a stirrer, a thermometer, a nitrogen blowing tube, and an exhaust tube, 150 g (1 mol) of a higher alcohol acrylate with a carbon number of C ₂₀ to C ₂₆ and lauryl alcohol (Calcol 20 155 g (0.25 mol) of acrylate, a 30 mol adduct of ethylene oxide (Kao product) and 305 g of toluene were heated and dissolved at 40°C, and 0.3 g of azobisisobutyronitrile (AIBN) and 2 ,2′-Azobis-
2,4-dimethylvaleronitrile (ADVN)
0.45g was added. The temperature was further raised to 70°C, and a polymerization reaction was carried out at the same temperature for 7 hours. Continue to be 110-120℃
and toluene was removed under reduced pressure. The obtained copolymer was a pale yellow solid, and the number average molecular weight was 32,000 as determined by gel permeation chromatography (GPC). This copolymer was used as the additive of the present invention. The higher alcohol of the _C20 to _C26 higher alcohol acrylate was a commercially available product "Alphor 22" (manufactured by Continental Oil Co., Ltd.), and the carbon number composition was as follows.

[Table] Examples 2 to 6 Copolymers were produced in the same manner as in Example 1, except that the raw materials shown in Table 1 were used, and used as additives of the present invention.

[Table] Comparative Example 1 300 g of higher alcohol acrylate having a carbon number of C ₂₀ to C ₂₆ and 300 g of toluene were placed in a 1 liter glass four-necked flask equipped with a stirrer, a thermometer, a nitrogen blowing pipe, and an exhaust pipe. The mixture was heated and dissolved at 40 DEG C., and 0.3 g of azobisisobutyronitrile and 0.45 g of 2,2'-azobis-2,4-valeronitrile were added as polymerization initiators in a nitrogen atmosphere. The temperature was further raised to 70°C, and a polymerization reaction was carried out at the same temperature for 7 hours. Subsequently, the temperature was raised to 110-120°C, and toluene was removed under reduced pressure. The obtained polymer was a yellowish brown solid, and the number average molecular weight was 50,000 as determined by gel permeation chromatography. This material was used as the additive of Comparative Example 1. Comparative Examples 2 to 3 Copolymers were produced in the same manner as in Example 1 except that the raw materials shown in Table 1 were used. Comparative Examples 2 to 3
It was used as an additive. Test Example 1 Additives of the present invention in Examples 1 to 6 and Comparative Example 1
The following tests were conducted to see the effects of comparative products No. 3 to 3. The fluidity was evaluated by adding the additive to three types of crude oil and measuring the pour points and viscosity at low temperatures of the oils prepared. The measurement results are shown in Tables 2 and 3. (Pour point depressing ability measurement method) Additives are added and dissolved to a predetermined concentration in crude oil for evaluation that has been preheated to 40 to 50°C. Then, it was placed in a 98℃ bath for 10 minutes, -17℃ bath for 20 minutes, and a 48℃ bath for 25 minutes.
The pour point is measured according to JISK2269, which is soaked for a minute to erase the thermal history. (Viscosity measurement method) The crude oil for evaluation in which the above additives have been added and dissolved to erase the thermal history is cooled to a measurement temperature, and the viscosity is measured using a B-type viscometer.

[Table] Crude oil-3: Southeast Asian crude oil

[Table] As is clear from Tables 2 and 3, it can be seen that the fluidity improving additive of the present invention provides superior fluidity compared to Comparative Example 1, which is a conventionally used polyalkyl acrylate. .

Claims (1)

[Scope of Claims] 1. (Meth)acrylate (a) of aliphatic alcohol (with 12 or more carbon atoms) and (meth)acrylate of alkylene oxide adduct of aliphatic alcohol
A crude oil fluidity improving additive characterized by containing a copolymer with (b). 2. The additive according to claim 1, wherein the aliphatic alcohol in (a) is a straight chain aliphatic alcohol having 16 to 30 carbon atoms. 3. The additive according to claim 1 or 2, wherein (b) is a (meth)acrylate of an ethylene oxide or/and propylene oxide adduct of an aliphatic alcohol having 6 or more carbon atoms. 4. The additive according to any one of claims 1 to 3, wherein the molar ratio of (a) and (b) is in the range of 1:0.03 to 1:10. 5. The additive according to any one of claims 1 to 4, wherein the copolymer has an average molecular weight in the range of 3,000 to 100,000.