At first the government tried to convince them to do different industries to factories to recycle such material. And now instead recycling is increasing every day due to its cost equals two thirds of the raw materials produced.
In the worldwide market there are fifty different types of plastic. The polyethylene plastic used for soda bottles is one of the types of recycled plastic in greater quantity. Recycled polyethylene are currently manufactured carpets, auto parts and balls for tennis.
The separation of different plastics is costly, since many products, including bottles containing sauces, are five to six layers of different plastics and for a new product, high quality, it is necessary to use each type separately. Every day new applications are discovered for the recycled plastic: soft drink containers, hooks for hanging clothes, toys etc.
Plastics that are in the market are differentiated by a number from "1" through "7", usually located on the bottom. This is the classification of the Society of the Plastics Industry (SPI in English) which has been adopted worldwide. Since the quality of a plastic deteriorates rapidly when combined with other plastic different, the usefulness of this code is to assist in the separation of different types of plastic and maximize the number of times they can be recycled. The meaning of this code is shown below:
Number Abbreviation Full name
1 PET, PETE polyethylene terephthalate
2 High Density Polyethylene HDPE
3 V, PVC polyvinyl chloride
4 LDPE Low Density Polyethylene
5 PP Polypropylene
6 PS Polystyrene
7 other
Under "other" we can find plastic such as polyurethane (PU), acrylonitrile-butadienestireno (ABS), polycarbonate (PC) and the biopolymers.
PVC
The abandonment of the plastic PVC, identified by Greenpeace as a toxic, environmentally harmful and unsustainable, represents much of the work done by the organization. PVC is unique in its chlorine content and additives, which makes it an environmental poison throughout its life cycle, including disposal. Recycling is very difficult to do, and cremation generates carcinogens such as dioxins. In Mexico, 55% of PVC is used in the manufacture of rigid pipe and profiles, while the rest goes to the production of toys, floors and tile, upholstery, packaging, footwear, cables and film among others.
PVC plastic is not the only obvious risks, as there are others that also generate toxic emissions and present difficulties for recycling.
PU
Polyurethane is used primarily as insulation. Its production consumes about 11% of world production of chlorine, uses many hazardous intermediates and creates numerous toxic byproducts such as phosgene, isocyanates, toluene, diamines and CFCs among others. The burning of PU releases numerous toxic compounds, including hydrogen cyanide, and dioxins (if present halogenated flame retardants or CFCs). It was noted that the buried, PU foams degrade toxic leachate generated. The PU is the second most toxic plastic in the market. According to the industry, flexible PU foam is recycled into other products of high quality. Despite being less problematic than PVC, PU use is not recommended as an alternative to PVC.
PS, ABS, PC
While the production of polystyrene (PS) involves the use of carcinogens such as benzene, and others are suspected carcinogens such as styrene and 1,3-butadiene, this film requires far fewer additives than PVC. During his burning is released again styrene and some toxic hydrocarbons, generating hydrogen chloride and dioxins if present halogenated flame retardants. The PS technique can be recycled, although the recovery rates are low. It is also not recommended as a substitute for PVC.
The ABS (Acrylonitrile-butadienestireno) is a hard plastic used in pipes, fenders of cars and toys. Its production uses besides styrene butadiene and acrylonitrile, a highly toxic. Given its complex chemical composition, the ABS is extremely difficult to recycle.
Moreover, compact discs and jugs of water of 19 liters usually are made of polycarbonate (PC). The PC does not need additives but their production is employed phosgene and solvents such as trichloroethane and chlorobenzene in addition to bisphenol-A, an endocrine disruptor frequently used. Currently processes are explored to produce PC without these compounds. We have designed some PC recovery processes for the production of lower quality.
PET
PET is the most commonly recycled plastics in the U.S. and Europe. Is generally used in cans and bottles and often contains stabilizers and flame retardants. The total amount of pigments and additives it contains may reach 30% by weight. Its production and irritants used during production can be used heavy metals as catalysts, same will eventually be released into the environment. However, PET is considered to not cause severe health impacts, and represents a lesser risk to the environment than PVC. Greenpeace believes that the recycling of PET, as well as plastics that are mentioned below, should be encouraged.
HDPE, LDPE, PP
Polyolefins such as PE and PP containing simple structures that do not require the addition of additives (plasticizers), but used additives such as UV stabilizers and antioxidants. PP production often uses chlorine, although there is a chlorine free process that should be promoted. The polyolefins have few risks and have the highest potential for mechanical recycling. Both PE and PP are versatile and inexpensive, and can be used to replace virtually all uses of PVC. The raw materials used, ethylene and propylene, are highly flammable and explosive, but little damaging to the environment.
Biopolymers
The vast majority of plastics are made from oil and fossil fuels are by definition non-sustainable. Biodegradable plastics are a promising alternative for the future, especially for vessels that have a reduced life or are not practical to recycle, such as food wrappers. Degradation products (methane, methanol) can be reused and the remaining material transformed into organic carbon to soil, thus closing the cycle of clean production.
Do not confuse biodegradable plastics (which can be produced from oil, and subsequently be degraded by microorganisms) with the biopolymers produced from starch, cellulose or bacteria. It is essential, however, that the production of biopolymers not involve the use of genetically modified organisms, patents on these beings. http://thechemistrysideoftheforce.blogspot.com/
What we need is to take a clean production process and the selection of raw materials used. Clean production systems are circular, ie close the cycle of extraction of natural raw return as the environment clean and sustainable. The recycling of waste is an essential step to maintain an adequate flow of materials, for which it must also involve the use of toxic substances during their production.
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