JPS602342B2 - oil adsorbent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adsorbent for hydrocarbon oil floating on the water surface,
This invention relates to an oil adsorbent whose main component is crude linter.

More specifically, it consists of an aggregate of coarse linters or 10 to 7 parts by weight of crude linters as a binder.
3 parts by weight of a fibrous or powdered thermoplastic synthetic polymer or thermoplastic semi-synthetic polymer is mixed with a binder, and the crude linter is mixed into a mat or slightly burnt rope shape (hereinafter referred to as strand shape). The invention relates to an oil adsorbent which is fixed in the molded state by heating the thermoplastic polymer 2 in a molded state above the melting point of the thermoplastic polymer 2 and cooling it.

Currently, adsorbents for hydrocarbon oils that float on water surfaces include those made from cellulose materials such as pulp and rayon, and those made from synthetic polymer compounds such as polypropylene (PP) and polyurethane 2 (PU). It is used. However, although cellulose is an oil-absorbing material, in order to give it buoyancy on water, it is generally necessary to perform water repellency treatment, which is expensive and also requires sacrificing some of the oil-absorbing properties of cellulose. ing. In addition, materials such as PP and FU have a specific gravity of less than 1, but are selected as molded products containing closed cells that provide buoyancy on water surfaces and are compatible with Germany. When incinerated, scales have the disadvantage that they generate harmful gases or the exothermic silica is too large and can damage the scale incinerator.

Furthermore, since the material itself is not biodegradable, there is a risk of secondary pollution caused by spillage of the oil absorbent. In view of the above, the present inventor has discovered that there is no risk of attracting secondary pollution, and the oil adsorption capacity is high.
As a result of various studies on oil-absorbing materials that have low water absorption and are available at low cost, we found that unrefined crude linter, which is collected from cottonseed, contains a thin amount of oil and fat, which makes it difficult to adsorb oil such as heavy oil. It has been found that the material can provide an ideal oil adsorbent because it is of good quality and has well-balanced properties with vertical water properties suitable as an oil adsorbent and is available at a low price.

The oil in the present invention is a hydrocarbon oil, such as turbine oil, kerosene, gasoline, B heavy oil, C heavy oil, etc., which float on water surfaces.

Therefore, for example, if a small amount of waste oil, in some cases, the crude linter is directly thrown into the water surface containing waste oil such as heavy oil or turbine oil, and the crude linter is allowed to adsorb the waste oil such as heavy oil or turbine oil, or The crude linter is stored as it is in a bag-like net, and the waste oil is adsorbed by the furnace.

In addition, if the amount of waste oil is large and the fiber length of the crude linter is long, either form it into a strand or mat shape to absorb the waste oil, or use a short fiber length such as a second-cut linter or a hull coarse linter. (If the tensile strength is extremely low when formed into a strand or mat, it may be stored as is in a bag-like net, or a thermoplastic synthetic polymer or thermoplastic semi-synthetic polymer with a relatively low melting point may be used as a binder for the coarse linter.) Mix about 10 to 3% by weight of the combined materials and form into a strand shape or mat shape, etc.
Create an oil adsorbent with high tensile strength and use it to adsorb waste oil. The binder of the present invention is a fibrous or powdered thermoplastic polymer or semi-synthetic polymer, which is mixed with a crude linter and heated above the melting point of the thermoplastic polymer or semi-synthetic polymer, Thereafter, cooling acts to form the aggregate of coarse linters into a mat or strand shape.

That is, the heat-fusibility of thermoplastic polymers or semi-synthetic polymers;
The coarse linter aggregate is molded using thermoplasticity.

As thermoplastic polymers for the binder, PP, ethylene propylene copolymer (EP), polyethylene vinyl acetate copolymer (EVA), PU, polyester, nylon, polyvinyl alcohol resin, etc. are used, especially PP or EV.
A is preferred. Semi-synthetic polymers are chemically modified natural polymers such as cellulose, such as cellulose acetate and cellulose propionate, with cellulose acetate being preferred.

Among semi-synthetic polymers, those which are thermoplastic and have a relatively low melting point, for example, those having a melting point of 250° C. or lower, can be used as binders in the same way as thermoplastic synthetic polymers having a relatively low melting point.

Moreover, even when 10 to 3% by weight of thermoplastic synthetic polymers or thermoplastic semi-synthetic polymers are mixed, the amount of oil adsorption is extremely large and the amount of water absorption is low, such as synthetic fibers such as PP or PU.
It has been found that it is possible to provide an extremely superior oil adsorbent in practical use because it does not cause secondary oxidation compared to the case where the amount is 0% by weight. When the amount of thermoplastic synthetic polymers or semi-synthetic polymers mixed as a binder is less than 1% by weight, the strength of the oil adsorbent of the present invention when formed into a mat or strand shape increases. If the amount exceeds 3% by weight, it may cause pollution due to synthetic or semi-synthetic polymers, so they cannot be used together. Furthermore, crude linters also have adsorption capacity for non-aqueous organic solvents such as aromatic hydrocarbons and aliphatic hydrocarbons.
It can be used as a treatment material for wastewater containing these non-aqueous organic solvents.

Many commercially available oil absorbent mats lose their shape when exposed to organic solvents and cannot be used.

In the case of crude linter, since the crude linter itself does not dissolve in organic solvents, it can be used for adsorbing organic solvents by using a solvent-resistant binder.

- The performance required of oil adsorbents as specified by the Isoko Transport Ministry Ordinance is as follows.

The amount of adsorption by heavy oil B is 6 or more per night on the oil adsorbent, and 0.
Must be 8 ta or above.

{Low Water absorption amount should be 1.5 ta or less for the adsorbent 1 and 0.1 ta or less for the oil adsorbent 1.

1. The material does not change easily under normal storage conditions1.
To be something.

(1) It should not settle for a long time while adsorbing oil, and there should be no dimensional change or deoiling phenomenon.

Target: Easy to collect after use.

N: Can be incinerated and generates only a small amount of harmful gas due to incineration.

As is clear from the following examples, the oil adsorbent of the present invention satisfies all of the above-mentioned properties.

Next, the present invention will be explained in detail by way of examples. Example 1
'[a} Regarding adsorption rates for various oils.

Table 1 shows the results of a comparative test between the oil adsorbent of the present invention and a commercially available oil adsorbent. The samples contained 0.0% oil adsorbent. I used spots.

Table 1 Comparison of oil adsorption rates of various oil adsorbents Here, the crude linter mat of the present invention is composed of coarse linter and thermoplastic polymer fibers. and thermoplastic polymer or copolymer fibers in the respective weight ratios and fed to a cotton making machine.The resulting web was sandwiched between two wire meshes, a load was applied, and a hot air dryer was used to dry the web at 110% by weight. ~15 bi○, 20~3
It is formed into a matte shape by heat treatment for 0 minutes.

For example, in Table 2 below, there are three types of mats with almost the same square footage, but these are examples of mats with different thicknesses and densities depending on how the load is applied when sandwiched between wire mesh. be.

2. Also, the results shown in Table 3 show that when a large load was applied and the density was set to about 0.3, excellent results were obtained in both oil absorption and physical properties. Weight % of crude linter mat A and crude linter 8.

Tricopolymer fiber (EVA) containing 9% by weight of ethylene and 7% by weight of vinyl acetate (trade name: Rheofil PE manufactured by Daiichi Race Co., Ltd.)
A) Mat consisting of 20% by weight. coarse lintermat B,
Weight % of crude linter 9.

Ethylene, propylene copolymer fiber 3 (EP) specific gravity 0.
94" (made by Yamato paper, BF type) A mat consisting of 1% by weight.

Weight % of crude linter mat C and crude linter 8.

A mat consisting of 2% by weight of polypropylene fibers (manufactured by Yamato Tsuzuri, specific gravity 0.92).

4 Commercially available oil adsorbents L, T, and W are all dry nonwoven fabrics made of polypropylene fiber webs fixed using adhesives, and their respective composition ratios are the same, but their physical properties are different from those of coarse linter mats A, B, and B. As in the case of C, as shown in Examples 1, 2, and 3, the present inventors measured the tsubo (Y/J) and thickness (Ki) each time, and determined the high density (J/J). As shown in Tables 3, 4, and 5, the thickness is the same, but the weight per square meter and the density are different. Commercial oil adsorption L used in Table 1
, T, and W are as follows.

The oil adsorption rate test was carried out as follows: (i) The crude lithotarmat of the present invention and the commercially available oil adsorbent were each manually torn apart and decomposed into fibers.

(In this case, the binder component is attached around the fibers.) (ii) The fiber length is set to 0. Collect as a paper sample.

(iii) Put a large amount of oil (100%) into the enamel pad against the above fibers. GW Float the whole fiber sample in the oil, observe the state in which the oil is absorbed by the fibers, and float the fiber sample in the oil. The time from this point until the entire fiber is completely contaminated with oil (referred to as full saturation) is measured and defined as the saturation point.

(The saturation point is achieved within 1 minute.) Oils such as kerosene, turbine oil, A heavy oil, C heavy oil, etc. are similarly measured.

Immediately after being released for another 5 minutes from the point of saturation, the sample was taken out and left on a wire mesh for 5 minutes, then its weight was measured and the oil adsorption rate was determined by the following formula.

Adsorption rate = WZ constant and X・oo W,: weight of the initial sample W2: weight of the sample after 5 minutes of incubation from the saturation point Regarding the observation of full saturation mentioned above, since the oil is black in color, Fully saturated is when the color is uniformly distributed throughout the sample.

The time required for this is significantly shorter than the subsequent 5 minutes of standing as described above.

The results in Table 1 show that the oil adsorption rate of the fibers used in the present invention is significantly higher than any of the commercially available products. In particular, the P listed in Table 1 shows an excellent oil adsorption rate among commercially available products.
Compared to the oil adsorbent of commercial product T, which is a dry nonwoven fabric made of P fibers, only the coarse linter and coarse linter mat A of the product of the present invention
It can be seen that when using , the following excellent self-adsorption rate is shown.

The reason why crude linter exhibits such an excellent oil adsorption rate as mentioned above is that while synthetic fiber oil adsorbents only adsorb oil onto the fiber surface due to the lipophilic properties of the fibers themselves, coarse linter shows an excellent oil adsorption rate. This is because the fiber structure is crimped and hollow, so waste oil is adsorbed on the fiber surface and penetrates into the fiber interior by capillary action, where it is adsorbed and occluded.

'b' Regarding the change in dimensions over time in the oil absorption state.

Dimensional changes (swelling) when heavy oil B is taken into a pad filled with seawater and the oil adsorbent crude lintermat B and commercially available products L, T, and W (listed in Table 1) are added and the whole surface absorbs oil. After it settled by making waves for several days, we tested whether it would lose its original shape or not. As a result, the swelling ratio immediately after oil absorption (area ratio before and after oil absorption) is as follows. Crude lintermat B, 0.05% commercial product L,
0.31% commercial product T,
0.18% 4 Commercial product W,
0.09% In this case, the crude linter mat B is composed of 9% by weight of crude linter and 10% by weight of ethylene propylene copolymer fibers, and the weight of the mat is 350 ta' and high. Density (evening/clump) is 0.
065 was used, and commercially available products L, T, and W were the same as those shown in Table 1.

The method for measuring the swelling ratio is to put 350 cc of seawater and 150 cc of B heavy oil into a enamel vat of 2&Makura x Shiaraki.

(In this case, heavy oil B will be floating on the sea surface.

) The sample is a mat piece (or non-woven fabric piece) of 10 skins x 10 arcs, floated on the liquid surface, taken out after 5 minutes, and placed on a wire mesh for 5 minutes.
After standing still for a minute, the dimensions of the side surface of the sample were measured, and the swelling ratio was determined from the ratio to the area of the side surface before dipping.

Side ratio = L2;

In the case of this example, there was no precipitate even after 5 days of immersion. The crude lintermat B of the present invention has a low swelling ratio,
Moreover, after 14 days, the oil adsorbents of each test sample did not settle, and no dimensional change or oil removal phenomenon was observed.

'c' Regarding gasoline solubility. A gasoline dissolution test was conducted on crude lintermat A and crude lintermat C (Table 1) of the present invention, and a immersion test was conducted for 1 sand interval, 10 minutes, and 2 Misakiju, but no change was observed in either case. It did not dissolve in gasoline*, and the commercially available L and T products lost their shape.

[d- Regarding oil absorption capacity on the sea surface.

The measurement results in Table 1 are oil absorption tests on the oil surface using only the oil of the oil absorbing material, but in the case of oil spilled on the sea surface, there is a thin oil film layer. Pour seawater into the tank, add 150cc of B heavy oil, and place the test piece of the present invention (1
The amount of oil absorbed and the oil absorption time were measured by floating the melon (melon radish) and measuring the oil absorption time.

The oil absorption amount is listed after Table 3.
The measurements were followed. The oil absorption time was determined by floating a test piece of Rinku Mat A, the size of one melon, on the oil surface, and measuring the saturation point when the entire surface of the test piece was completely contaminated with oil. It was decided that In Table 2, "r tsubo" refers to the weight per unit, and is commonly used in the paper and other industries, and the tsubo weight is abbreviated to tsubo.

In addition, the tsubo and thickness were measured and the high density was calculated as tsubo/thickness. From the results in Table 2, the smaller the density, the longer the oil absorption time.

From Example 1 above, it can be seen that the oil adsorbent using the coarse linter and coarse linter mat of the present invention has the following effects.

It has passed all the standards of the Ministry of Transport ordinance, and is about 1. It has a sound-sealing oil absorption ability.

'The cost of raw materials is low. 1. It selectively adsorbs only oils and hardly any water.

B. It does not settle in water. ■ Since it is made of natural cellulose, it is completely non-toxic and does not cause secondary pollution to marine products or emit harmful gases when incinerated.

N It maintains its original shape for a long time while adsorbing oil. [It is economical because it is easy to recover after using the oil adsorbent and can be reused.]

It does not dissolve in hydrocarbon organic solvents such as gasoline.

Meat Can also be used as an adsorbent for non-aqueous solvents.

Example 2 Performance tests were conducted on the crude linter and coarse linter mat of the present invention, as well as commercially available mats, based on the performance test method for oil adsorbents specified by the Ordinance of the Ministry of Transport. The results are summarized in Table 3.

Table 3 (Commercial products T L W are the same as in Table 1.

) * "Coarse Rinku Mat" is a thermoplastic polymer fiber; it is just a wet cloth because it contains fibers. Therefore, there are no measurements of strength. ※※The amount of thermoplastic polymer is too small, and the strength is extremely low/''・Measured values have been omitted.

Pour a) Oil absorption: 1 piece of 10cxlo 20g test piece
Float it in oil K at ℃ and let it stand for 5 minutes, then leave it in the dark for 5 minutes on a wire mesh with a wire sieve with a diameter of 1 and the length of the mesh on the 1.7 side. Then, measure its weight.

Calculate the oil absorption amount per weight of the test piece and per volume of the test piece. The B heavy oil used in this test has a specific gravity of 0.90 to 0.91 at 15°C. Viscosity 15-30C
ST (50''C) is standard.

In addition, in calculating the capacity, the thickness of the test piece is 79 per 1
Measure under a load of (1) Float one 10 x loc test piece on the water surface at 20°C for 5 minutes, then leave it on a wire mesh of the same size as in the previous item (a) for 5 minutes. Measure its weight.

Calculate the water absorption amount per 19 weight and per 1 volume of the test piece. (c) Measurement of tensile strength using test piece 2.50 x 8
Willow, tensile speed 8/mn, gripping interval 6, temperature 20℃
It was carried out in From the results in Table 3, the 'a' crude lintermats A, B, and C all have values that exceed the standard values specified by the Ministry of Transport ordinance, and are superior to commercially available products.

'b' The oil absorption amount per weight and per volume is related to the density, and there is a contradictory relationship, but the density of the mat is 0.05~
0.20/more is better.

'c- The water absorption amount of the oil adsorbent of the present invention is significantly smaller than the standard value.

'd- The tensile strength of the product of the present invention is
Although it seems to be slightly inferior to commercially available products, there is no difference in the oil absorption state during actual use, and the oil adsorbent of the present invention has sufficient tensile strength when used.

The melting points of the synthetic polymers as binders used in the present invention are, for example, PE120°C, EVAIOO~140Z°C.
, PP 150 to 17,000 and a melting point of this level is desirable for matting.

Example 3 Pour 500 cc of water into an IZ beaker, add 200 cc of gasoline or benzene to it, and use it as the clearest liquid.
Test pieces (5 x 5) of the present invention and a commercially available adsorbent were introduced.

All oil adsorbents floated on the water surface and immediately adsorbed gasoline or benzene. Within 1 second, they were completely contaminated with oil by naked eye observation and reached the saturation point, so they were removed from the immersion liquid and placed on a wire mesh for 1 minute. Immediately after, the weight was measured and the amount of oil adsorption was determined.

The oil used in this example had a low viscosity and quickly reached the saturated oil absorption as described above.As a test condition, the oil adsorbed amount was poured into a mulch solution, left for 1 minute, then withdrawn, and placed in a wire mesh as described above. Immediately after standing still for 1 minute, the weight was measured to determine the amount of oil adsorption.

The results are shown in Tables 4 and 5.

Table 4 Table 5 Cellulose acetate listed in Tables 4 and 5 both have an acetylation degree of 552.
%.

Vertical acetic acid fibers with a polymerization degree of 180 and a thickness of 8 denier were used. From the results in Tables 4 and 5, it can be seen that the oil adsorbents of the present invention are superior in adsorbing amounts of gasoline and benzene than any of the commercially available products.

Claims (1)

[Claims] 1. An oil adsorbent made of crude linter. 2. Mixing 10 to 30 parts by weight of fibrous or powdered thermoplastic synthetic polymers or thermoplastic semi-synthetic polymers as a binder to 90 to 70 parts by weight of crude linter,
An oil adsorbent made by forming crude linter mixed with a binder into a pine-like or slightly twisted rope-like shape by heating above the melting point of these polymers and then cooling.