JPS6211039B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an oil-absorbing material that is easy to operate and has high oil-water separation performance. [Prior Art] With the progress of industrialization, various petrochemical materials useful in human life have been developed, and cultural activities have begun to take place. On the other hand, in the process of developing and manufacturing petrochemical materials, raw materials, auxiliary agents,
By-products, products, or parts of waste may leak outside in some way, contaminating the environment,
The purpose of originally serving to improve the cultural life of humankind is
On the contrary, it has reached a state where even the survival of humanity is threatened. To take it to the extreme, in order to obtain large quantities of products at low prices,
It is easy to dispose of unnecessary things by the so-called ``flushing'' method, and we must understand that the fact that this process was carried out not only by manufacturers but also in the lives of individuals is a major cause of today's environmental pollution. It won't happen. Modern life cannot be considered inseparable from petroleum, but some of the waste produced in the manufacturing process of products that use petroleum, and the waste that is produced after using those products, are more or less indispensable. ,
So-called waste oil is mixed in. Not only that, but there are many cases where waste oil is mixed into what is considered to be just wastewater. In particular, in recent years, as industrial wastewater and the number of ships entering and exiting ports continue to increase, river and seawater pollution from waste oil has increased, and problems such as negative effects on water and marine resources and fires have become serious. Unless oil and water are separated, not only from the waste that is about to be disposed of, but also preferably from parts that have already been contaminated with waste oil, it will not be possible to live a safe life. For this reason, many oil-water separation materials (agents) and oil-water separation devices have been developed. However, most of the oil-water separation materials that have been developed to date are made of fibers or porous materials made of organic polymers, requiring complicated manufacturing methods and high costs. In general, the idea that ``it is not economical to spend a large amount of money for disposal'' still persists, and the reality is that this type of expensive oil-water separation material is not being used to its full potential. On the other hand, in the manufacturing process of silicones, RSi
Cl ₃ , (R is CH ₃ , C ₂ H ₅ , C ₃ H ₇ , C ₂ H ₃ or
A large amount of C ₆ H ₅ ) is produced as a by-product, and when this is added to water, silsesquioxane (RSi O _{3/2 )} is formed. It had been. However, as the disposal itself has become a problem these days, manufacturers of various silicone products have been struggling to deal with the issue. By the way, it was obvious that this silisequioxane (RSi O _3/2 ) _o itself has oil absorbing properties and that it was cheap because it was industrial waste, but in general, this material was made of glass-like blocks. Or, because it is a powder, it is only possible to absorb oil on the surface if it is in glass form, and although powder absorbs a large amount of oil, it is complicated to handle, so the reality is that it is not used effectively. It was hot. [Problems to be Solved by the Invention] In view of this situation, the present inventors used silsesquioxane (RSi O _{3/2 )} , which is the above-mentioned industrial waste, to develop a method that is inexpensive, has a large amount of oil absorption, and is easy to handle. They conducted extensive research to create a simple oil-absorbing material and arrived at the present invention. That is, an object of the present invention is to provide an oil-absorbing material that is inexpensive and easy to handle. [Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration. "A composition comprising 3 to 80 parts by weight of an alkali silicate component represented by the following formula [] and 97 to 20 parts by weight of a silsesquioxane component represented by the following formula [], _An oil-absorbing material _{characterized} by having a foam structure. ) (RSi O _3/2 ) _o ... [] (However, R is -CH ₃ , -C ₂ H ₅ , -C ₃ H ₇ , -
C ₂ H ₃ or -C ₆ H ₅ (phenyl group), n
indicates the degree of polymerization. )” Silsesquioxane (RSi O _{3/2 )} , one of the components of the present invention, has low polarity and strong water repellency, whereas alkali silicate (or its raw material) has low polarity. Although it is highly hydrophilic and inherently incompatible with polarity,
(RSi O _3/2 ) The molecular terminal of _o is thought to be -Si-OH, and the two often coalesce, probably because this chemically bonds with the alkali silicate (or its raw material) (a type of block copolymerization). do. At the same time, alkali silicates or their raw materials have the property of foaming when heated in the presence of water. Therefore, according to the present invention, even if (RSi O _3/2 ) _o is used as a powder that is difficult to handle, it will coalesce with the alkali silicate.
It can be formed into various shapes, and since the alkali silicate itself foams, it is possible to form an oil-absorbing material of any shape and with a large surface area. The alkali silicate component represented by the formula [] in the present invention may be an alkali silicate itself, or may be started from a raw material that produces an alkali silicate. Such raw materials include _SiO2 at 50%
It consists of a mixture of a silicic acid raw material containing more than % by weight and an alkaline raw material containing Na or K, and when heated to a temperature that foams in the presence of at least water, part or all of it becomes an alkali silicate raw material. Something that becomes something. Siliceous raw materials that can be used for this purpose include natural products such as diatomaceous earth, silica stone, silica stone, silica sand, and silicate clay, pozzolans that are by-products in the manufacturing process of metallic silicon and silicon alloys, and various metals. These include slag or fly ash from scouring. There are many alkaline raw materials such as sodium hydroxide, potassium hydroxide, sodium oxide, and potassium oxide. In the present invention, the alkali silicate may be a completely alkali silicate, a mixture of a silicic acid raw material and an alkaline raw material, or an intermediate thereof, or a mixture of both. . In the present invention, the molar ratio of SiO ₂ /A ₂ O is from 2 to
A range of 25 is required, particularly preferably between 2.5 and 15
is within the range of If this molar ratio is lower than the above range and the proportion of (RSi O _3/2 ) _o added is small, the water resistance will be poor and the durability of the product will be poor, which is not preferable.
On the other hand, if this molar ratio is high, foaming properties will be poor,
This is not preferred because the surface area of the product is small and the oil absorption performance is reduced. In the present invention, the mixing ratio of the alkali silicate component (abbreviated as S) and silsesquioxane (abbreviated as C) is 3 to 80:97 to 20 by weight (however, S:
The range C) is good, particularly preferably 30-80:70-
20 (however, the range of S:C) is good. If the ratio of (RSi O _3/2 ) _o is lower than the above range, sufficient oil absorption effect will not be exhibited, and conversely, if it is higher than the above range, the oil absorption will decrease, probably due to the smaller surface area, and it will be easier to handle. This is not desirable because it makes it difficult to freely form shapes. Further, in the present invention, the Si/Na ₂ conversion ratio in all raw materials is 3.5 or more, preferably 5 or more. The reason for this is that it falls under the category of ordinary glass or other ceramics, and after being incinerated or otherwise treated, it becomes completely harmless to humans and animals. This ratio is 3.5
If it is less than that, the alkaline content of the residue will be too strong even if it is incinerated or otherwise treated after oil absorption, causing problems. Next, R in silsesquioxane (RSiO _3/2 ) _which is a compound of formula [] is -CH ₃ , -C ₂ H ₅ , -C ₃ H ₇ , -C ₂ H ₃ , -C ₆ H ₅ (phenyl group). The reason for this is that most of the compounds discharged as by-products in general silicone factories have this structure. If this or that material is used, the raw material cost is low, so it can be made into a low-cost oil absorbing material. Further, n in the compound of formula [] simply indicates a polymer, and it can be used in the present invention without particular limitations. In other words, it is generally difficult to determine the degree of polymerization n for inorganic compounds; for example, quartz glass is a polymer of SiO ₂ , so strictly speaking,

〔Example〕

Examples will be described below. Example 1 First, 60 parts by weight of dry powder of (CH ₃ SiO _3/2 ) _o was added to 100 parts by weight of a 40% by weight aqueous caustic soda solution, and heated at 90° C. for 30 minutes to cause a partial reaction. The above (CH ₃ SiO _3/2 ) _o is a glassy (crosslinked structure) obtained by adding CH ₃ Si Cl ₃ to water.
It is a powdered product that is washed with water, dried, and ground into 150 to 250 mesh pieces. Next, 120 parts by weight of water was added to the partial reactant and cooled to room temperature, which was then produced as a by-product during the production of ferrosilicon.
SiO ₂ and 150 parts by weight of silica dust containing 96% by weight were added and mixed to obtain a slurry. This product was placed in a polyethylene bag and reacted at 40°C for 16 hours to obtain a solid block. The obtained reaction product (mixed composition) was as follows. 0.5Na ₂ O・2.4SiO ₂ ; Approximately 175 parts by weight (CH ₃ SiO _3/2 ) _o ; 60 parts by weight Therefore, in the former compound, A in the above formula [] is Na.
In this case, y/x was 4.8, and the latter compound was exactly the same as the above formula []. When the total reaction product obtained was 100 parts by weight, the weight ratio of the former compound to the latter compound was 74:26. The reaction product was crushed and the crushed particles (a) were collected using a filter of 45 meshes or more and 5 meshes or less. Next, a portion of this (a) was taken and heated in a rotor at 300°C for about 5 minutes to foam it in a water-containing state. As a result, foamed beads (b) with an apparent specific gravity of about 0.5 and an average size of about 4 meshes were obtained. 10 g of this (b) was added to 1 liter of wastewater from a polystyrene suspension polymerization tank (1600 ppm styrene dispersed in water, slightly dissolved in water, mostly in an emulsion state) and stirred at room temperature for about 5 minutes. Then, when the entire amount was passed through a 60-mesh wire mesh, a clear liquid was easily obtained. It was also found that the styrene content in this liquid was reduced to 240 ppm, confirming that the foamed beads were easy to operate and had extremely high oil absorption. Comparative Example 1 Instead of using 10 g of foamed beads (B) obtained in Example 1, 10 g of powder (150 to 250 mesh) of (CH ₃ SiO _3/2 ) _o , that is, only the compound of the formula [] of the present invention, was used. The same oil absorption operation was performed using Next, this material was passed through a cloth made of nylon taffeta, but it became clear that the cloth was clogged to a large extent, and drainage was difficult, and the operation required more than 10 times the time compared to the method of Example 1. Ta. Moreover, when this powder was used, it rose up in the air currents in the draft, making it essentially difficult to handle. Also, the oil absorption efficiency is approximately
It was extremely bad at 1/3. From the above experiments, it was found that a good product could not be obtained unless the compound of the formula was also present. Example 2 The particles (a) in Example 1 were heated at 90° C. for 30 minutes to foam them in a water-containing state to obtain foamed beads (c). Outer diameter of this (c) 50g with flanges on both ends φ = 60.5
packed in a galvanized steel pipe with a length of 50 mm, and the flanges at both ends were temporarily closed with iron plates, leaving the steel pipe standing.
Heated at 300°C for 1 hour. After cooling, when the iron plates at both ends were removed, the inside of the steel pipe was almost completely filled with the above (c).
The secondary foamed material was attached in a semi-molten state, and it also adhered well to the steel pipe. In other words, (c) was trapped inside the steel pipe like a glass filter. Therefore, this steel pipe is coated with oil mainly composed of toluene.
Connect the water pipe for waste liquid containing 2050ppm,
When the wastewater was experimentally flowed at 1m/min, the oil content in the wastewater that permeated through the steel pipe was already 800ppm.
It was found that there was a decline in As a result, it became clear that extremely simple oil-water separation was possible. [Effects of the Invention] The oil-absorbing material according to the present invention has unexpectedly excellent oil-absorbing performance (oil-water separation performance). Although the exact principle behind this is not clear to the inventors, it is important to note that the highly polar alkali silicate and silsesquioxane (RSi)
_This is because there is a part where _O is chemically bonded, forming a type of block copolymer, which exhibits a surfactant effect and has the property of containing an oil component. It is believed that there is. It is also considered that continuous foaming is preferable. As mentioned above, the oil-absorbing material according to the present invention has a composition that falls within the category of glass or ceramics after incineration, and is not a fine powder. It can be used as a raw material for inexpensive ceramic products, and it is also porous.
Since it is mainly composed of SiO ₂ , it can actually be used as a dehumidifier. In addition, when oil is absorbed by the oil-absorbing material of the present invention, if the oil component is a high-grade chemical product such as a raw material for perfumery or an expensive monomer, the oil component is recovered and removed by distillation as it is, and the oil component is used again as an oil-absorbing material. can be used. Furthermore, since the oil absorbing material of the present invention reuses industrial waste, it can be made at low cost.

Claims (1)

[Claims] Alkaline silicate component 3 represented by the linear formula []
80 parts by weight, and 97 to 20 parts by weight of a silsesquioxane component represented by the following formula [), wherein the composition has a foam structure. x・A ₂ O・y・Sio ₂ ... [] (However, A represents Na or K, and the molar ratio of y/x is in the range of 2 to 25.) (RSiO _3/2 ) _o ... [ ] (However, R is -CH ₃ , -C ₂ H ₅ , -C ₃ H ₇ , -
C ₂ H ₃ or -C ₆ H ₅ (phenyl group), n
indicates the degree of polymerization. )