JP2008280493A - Method for separation treatment of plastic leathercloth and plastic wallpaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate extreme difficulties experienced in recycling (reusing resources) of a plastic leathercloth, a plastic wallpaper and the like which have been mass produced, mass consumed and mass disposed because a woven fabric or paper being a substrate part of the plastic leathercloth or wallpaper is press-bonded or coated with plastic. <P>SOLUTION: The reuse of resources from a plastic leathercloth or wallpaper can be achieved without seriously affecting the environment by separating the plastic leathercloth or wallpaper into a woven fabric part or a paper part being a substrate of the plastic leathercloth or wallpaper and a plastic part press-bonded with or coated onto the substrate, respectively, with use of a solution dissolving sodium peroxide in an aqueous sodium hydroxide solution. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a separation processing method that facilitates recycling (resource reuse) of plastic leather cloth or plastic wallpaper.

Background of the Invention

  The background of the present invention is that these products, which are widely used in vehicle interior materials, furniture, building interior materials, shoes, books, etc., are produced, constructed, processed, and used in wallpaper. A large amount is abandoned as industrial waste at the time of interior renovation.

  In addition, since these products are in close contact with the woven fabric or paper as the base material, it is impossible to easily recycle (reuse resources).

  Plastics used in these products are soft polyvinyl chloride (PVC), polyurethane (PU), ethylene vinyl acetate copolymer (EVA), ethylene methyl methacrylate (EMMA), polyamide (PA), etc. in use.

  In addition, polyvinyl chloride products with large specific gravity, including wallpaper, use organic separation type foaming agents such as azodicarbonamide (ADCA), 4,4'-oxybisbenzenesulfonyl hydrazide (OBSH), etc. Are manufactured as foamed products.

  At present, these products are all incinerated or disposed of as landfills without being recycled (resource reuse).

In particular, when disposing of these products in which soft polyvinyl chloride is used for plastic parts, the problem of dioxins caused by polyvinyl chloride is a problem due to recent improvements in incineration technology. However, there are concerns about the impact of acidic components on the incinerator caused by hydrogen chloride generated by incineration.
Further, when landfilling is carried out, particularly when it is a foamed product, the bulk specific gravity is small and the landfilling efficiency is poor.

  The woven or paper parts of these products that are disposed of in landfills are degraded by enzymes contained in the soil, while the plastic parts are preserved in the soil for many years.

  The disposal of these industrial wastes as described above is not an appropriate disposal method from the viewpoint of the global environment, and it is considered that these industrial wastes are increasing in the future including wallpaper.

  For these products to be discarded as industrial waste, for example, wallpaper has been pulverized by mechanical means to separate the plastic part and the base paper by the difference in specific gravity. Separation is impossible. Alternatively, a method of dissolving and separating plastic with a solvent has been tried, but problems remain in terms of processing cost and environment.

  In the present invention, unlike these treatment methods, these plastic wastes discarded as industrial wastes can be easily treated with a sodium hydroxide solution containing sodium peroxide, so that the woven fabric or the base material can be easily obtained. By dissolving the fiber part of the paper, separating the plastic part as recyclable (resources recyclable), and recovering the solution part as cellulose fiber, the original component of the fiber, by neutralizing with hydrochloric acid is there.

  The present inventor has focused on recycling (resource reuse) of these products that are extremely difficult to reuse, and as a result of conducting sincerity studies, a solution obtained by dissolving a small amount of sodium peroxide in an appropriate sodium hydroxide solution It has been found that the fiber part of the product can be dissolved and completely separated from the plastic.

  The plastic separated by this method can be obtained by neutralizing sodium hydroxide remaining on the surface with dilute hydrochloric acid, washing with water and drying, and then having a physical property equivalent to that of the plastic provided.

  Moreover, it discovered that the cellulose fiber which is the main component of the melt | dissolved paper was isolate | separated and precipitated by neutralizing the solution part which isolate | separated the plastic with dilute hydrochloric acid.

  The specific means of the present invention is to cut these products to be recycled into a suitable size and to 100 parts by weight of 1% to 15% sodium hydroxide, preferably 5% aqueous sodium hydroxide. Further, 5 to 20 parts by weight, preferably 10 parts by weight, is added to 100 parts by weight of a solution in which 0.1 to 5 parts by weight, preferably 2 parts by weight of sodium peroxide is dissolved, and 30 to 70 ° C., preferably 50 ° C. By stirring for about 8 hours before and after, the paper part is completely dissolved and can be separated from the plastic part.

  The separated plastic portion is fractionated, neutralized with dilute hydrochloric acid so that the pH is slightly lower than 7, and the resulting sodium chloride is washed with water and dried to obtain a reusable plastic.

Cellulose fibers, which are precipitated by neutralizing the residual liquid from which the plastic portion has been separated with dilute hydrochloric acid until the pH becomes slightly less than 7, are thoroughly washed and reused as a raw material for woven fabric or paper.
Furthermore, these cellulose fibers are pure and free of impurities such as lignin, and are ground, decomposed, fermented and distilled to open the way to production of bioethanol.

  As described above, the present invention is an easy and environmentally friendly method for treating such products that are discarded, as a means for solving landfill processing, which is a problem in the current environment, or problems associated with incineration. It is an economically advantageous solution.

  Moreover, the plastics and cellulose fibers obtained by such treatment are obtained by reducing the odor of wastes used over a long period of time due to the bleaching action of active oxygen caused by the sodium peroxide used. The whiteness of each item is improved.

  Furthermore, the present invention provides a product whose base material is different from that of woven fabric or paper if the plastic part of each product is a common material such as soft polyvinyl chloride within a range in which the degree of polymerization does not greatly differ. Even so, it is possible to perform the separation process at the same time.

  Hereinafter, the present invention will be described by way of examples, but the present invention is not limited thereto.

  50 g of soft polyvinyl chloride wallpaper (product obtained from Takeno Co., Ltd.) appropriately cut into a solution of 20 g of sodium peroxide dissolved in 1 L of 10% aqueous soda solution, and stirred at 50 ° C. for 8 hours After that, the insoluble part and the solution part are separated.

  The insoluble portion was neutralized and washed with dilute hydrochloric acid and then sufficiently dried to obtain 39.3 g of soft vinyl chloride.

  100 parts of vinyl chloride resin (degree of polymerization 1100), 50 parts of DINP (di-isononyl phthalate), 2 parts of Ba-Zn liquid stabilizer and 30 parts of soft vinyl chloride obtained from insoluble parts are mixed to bring the surface temperature to 170. The mixture was kneaded for 5 minutes with two 6-inch test rolls maintained at 0 ° C., and a very uniform soft vinyl chloride sheet having a thickness of 0.5 mm and no fibrous material was observed.

  Further, the fibrous material precipitated by neutralization treatment is filtered off with a diluted hydrochloric acid of about 1/10 mol of the solution portion so as to have a pH of about 7 and then thoroughly washed and dried. Cellulose fibers originated from some paper could be obtained.

  A product obtained by cutting 70 g of interior soft vinyl chloride leather obtained from a vehicle dismantling company is immersed in a solution of 10 g of sodium peroxide in 1 L of 15% sodium hydroxide water and stirred at 60 ° C. for 5 hours. Separated into an insoluble part and a solution part.

  Thereafter, cellulose fibers caused by 49.7 g of soft vinyl chloride and 25.5 g of the woven fabric as the base material could be obtained by the same treatment as in Example 1.

Claims (1)

  Dissolve 0.1% to 5% sodium peroxide in 1% to 15% aqueous soda solution using a leather cloth or wallpaper made by pressing or applying plastic to one side of a woven fabric using paper or natural fiber as a base material. In the solution, the fiber part of the leather cloth or wallpaper is dissolved, separated from the insoluble plastic part, each is washed with acid neutralized water and completely separated into recyclable plastic and recyclable cellulose fiber. Separation method that makes it possible to recycle leather cloth or wallpaper.