Non-renewable sources

The simple fact is that the world s reserves of fossil fuels will eventually run out, depending on the rate of use, and therefore, if the consumption of these forms of energy are reduced, the existing reserves will last longer. Research and experimentation could lead to those reserves currently available but uneconomic to recover and use being rendered economic, thus extending further the number of years before these non-renewable sources of energy do eventually run out. 

They are derived from a non-renewable source, petroleum ... 

Use of renewable feedstocks is most likely where they can compete economically with petrochemically derived materials. This already happens in many areas, and it is sometimes forgotten that even in a world that seems to be dominated by chemicals and materials from fossil carbon and other non-renewable sources, industry already uses annually 19.8 MT of vegetable oils, 22.5 MT starch, 28.4 MT of plant fibres and 42.5 MT of wood pulp. These all compete on price and performance with synthetic alternatives. 

With the successful development and commercial manufacture of semi-synthetic Taxol , tile destruction of the Pacific yew tree forests was halted. However, this successful move away from an essentially non-renewable source (extraction of the Pacific yew tree bark) to a renewable source (harvested European yew tree leaves and twigs to obtain 10-DAB, followed by syntliettc transformation to Taxol ) still presented significant environmental challenges. The use of 13 different solvents. 

This adipic acid synthesis poses environmental and health concerns because it has benzene as a starting material. Benzene is a volatile organic compound and its inhalation can lead to leukemia and cancer. This compound, therefore, is often an occupational hazard to those who work with it or come in contact with it. Moreover, benzene is a byproduct of petroleum manufacture thus, it is produced from a non-renewable source. 

As discussed for mass intensity indicators, energy intensity indicators are simple to calculate but give only a partial overview of sustainability, as processes outside the chemical reaction or the chemical plant are not included. In addition, no discrimination is made between renewable and non-renewable sources, which have very different implications with regard to sustainability. Finally, the energy intensity related to material production (reactants, solvents, etc.) is also not included. As a consequence, energy intensity indicators must always be accompanied by material intensity indicators, which are measured in different units and cannot be directly aggregated. 

Table 2.2A, B C lists the non-fossil energy sources that are potential candidates to fill all or part of our future energy needs as defined in Table 2.1. They are divided into renewable sources, nonrenewable sources with relatively short lifetime and non-renewable sources with a long lifetime. In this context, a lifetime less than 100 years is considered short.

Table 2-2B Non-renewable sources with short use life ...

NON-RENEWABLE SOURCES WITH SHORT SERVICE LIFE... 

DC (direct current) electricity, which powers the electrolyzer, can come from a variety of renewable sources, such as wind generators, photovoltaic panels and small hydro and geothermal systems. Batteries are a common non-renewable source of DC current, as well as AC power supplies with rectifiers that change the AC to DC. 

Biotechnology research is seeking to develop new foods, feeds, fiber, and biomass energy production processes that are environmentally safe. Researchers are developing new uses for agricultural products to replace non-renewable sources of raw materials. Their work promises to have broad commercial applications and has already led to the creation of new industries. These discoveries have led to environmentally compatible commercial products such as biodegradable plastics (60), soybean oil printing inks, and super absorbent polymers (67). 

The properties of synthetic materials are hugely important to the sportswear industry they are inherently hydrophobic, thermoplastic, and demonstrate high-tensile strength, unlike natural and regenerated fibers that are absorbent but not as strong. Key polymer groups such as polyester and polyamide are conventionally synthesized from non-renewable sources at high cost to the environment. Efforts to find alternative... 

Hydrocarbon fuel is a non-renewable source of energy and it is well accepted that it would not last long. Research using alternate energy sources is being pursued seriously in many research labs worldwide. Use of renewable raw material includes ethanol, biodiesel, etc. Biomass appears to be the future energy source in addition to solar, wind, and wave. 

The raw materials used in the production of phenolic resins (phenol and formaldehyde) are obtained on a large scale from non-renewable sources. Therefore, the substitution of these reagents by equivalent chemicals obtained from non-fossil sources is an interesting alternative from both economic and environmental perspectives (Razera and Frollini, 2004 Hoareau et al., 2006 Paiva and Frollini, 2006). Moreover, substituting formaldehyde with other aldehydes obtained from renewable sources could eliminate the potential emission of formaldehyde during the use of phenolic resins (Ramires et al., 2010a). 

As seen, both adipic acid and catechol are obtained from benzene, which causes environmental and health problem. Also, benzene is produced from non-renewable source. In addition, in the synthesis of adipic acid, nitrous oxide is generated as a byproduct, which contributes to the greenhouse effect as well as destruction of the ozone layer. 

Bacterial cellulose has been used as a material in combination with many others to develop composites. It has been used with materials such as xmsaturated polyester [185], the conducting polymer polyaniline [158-162, 186], as well as various acrylic and phenolic resins [178, 187-189]. It has also been used with several biodegradable materials such as cellulose acetate butyrate (CAB) [146,190], PLA [167,174,191,192], PHB [193-195], PVA [196,197], and thermoplastic starch [198,199], to produce completely biodegradable composites. Though renewable and biodegradable composites are the focus of this review, techniques and resulting composites from non-renewable sources are also mentioned. 

In addition to PVOH and PLA, there are some other biodegradable polymers on the market these are listed in Table 1.1. These polymers are only produced on a small scale, primarily for biological applications, but also for exploration of commercial potential. Most of the biodegradable polymers are in the polyesters group. Biodegradable polymers can be derived from renewable and non-renewable sources (see Figure 1.4). Useful... 

On the last two pages you read about fossil fuels. These are finite or non-renewable sources of energy. Sooner or later, they will run out. So scientists are looking for other sources to replace them. 

Regarding other uses reported, ethyl lactate is being currently explored as green reaction medium for chemical synthesis and used as a route to produce 1,2-propanediol, chemical compound mainly used for the production of unsaturated polyester resins, which is actually produced from non-renewable sources on industrial scale. Moreover, as already pointed out, ethyl lactate production and subsequent hydrolysis can be used to obtain high-purity lactic acid. ... 

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