Isolation and Production
Carbon dioxide is mainly produced as an unrecovered side product of four technologies: combustion of fossil fuels, production of hydrogen by steam reforming, ammonia synthesis, and fermentation. It can be obtained by or from air distillation, however, this method is inefficient.
The combustion of all carbon-containing fuels, such as methane (natural gas), petroleum distillates (gasoline, diesel, kerosene, propane), but also of coal and wood, will yield carbon dioxide and, in most cases, water. As an example the chemical reaction between methane and oxygen is given below.
- CH4+ 2 O2→ CO2+ 2 H2O
The production of quicklime (CaO), a compound that enjoys widespread use, involves the heating (calcining) of limestone at about 850 °C:
- CaCO3→ CaO + CO2
Iron is reduced from its oxides with coke in a blast furnace, producing pig iron and carbon dioxide:
- Fe2O3+ 3 CO → 2 Fe + 3 CO2
Yeast metabolizes sugar to produce carbon dioxide and ethanol, also known as alcohol, in the production of wines, beers and other spirits, but also in the production of bioethanol:
- C6H12O6 → 2 CO2+ 2 C2H5OH
All aerobic organisms produce CO2 when they oxidize carbohydrates, fatty acids, and proteins in the mitochondria of cells. The large number of reactions involved are exceedingly complex and not described easily. Refer to (cellular respiration, anaerobic respiration and photosynthesis). The equation for the respiration of glucose and other monosachharides is:
- C6H12O6 + 6 O2 → 6 CO2 + 6 H2O
Photoautotrophs (i.e. plants, cyanobacteria) use another modus operandi: Plants absorb CO2 from the air, and, together with water, react it to form carbohydrates:
- nCO2 + nH2O → (CH2O)n + nO2
Read more about this topic: Carbon Dioxide
Famous quotes containing the words isolation and/or production:
“One of the most significant effects of age-segregation in our society has been the isolation of children from the world of work. Whereas in the past children not only saw what their parents did for a living but even shared substantially in the task, many children nowadays have only a vague notion of the nature of the parents job, and have had little or no opportunity to observe the parent, or for that matter any other adult, when he is fully engaged in his work.”
—Urie Bronfenbrenner (b. 1917)
“An art whose limits depend on a moving image, mass audience, and industrial production is bound to differ from an art whose limits depend on language, a limited audience, and individual creation. In short, the filmed novel, in spite of certain resemblances, will inevitably become a different artistic entity from the novel on which it is based.”
—George Bluestone, U.S. educator, critic. The Limits of the Novel and the Limits of the Film, Novels Into Film, Johns Hopkins Press (1957)