Recycle carbon dioxide

In photosynthesis, nature recycles carbon dioxide and water, using the energy of sunlight, into carbohydrates and thus new plant life. The subsequent formation of fossil fuels from the biomass, however, takes... 

Besides chemical catalytic reduction of carbon dioxide with hydrogen, which is already possible in the laboratory, we are exploring a new approach to recycling carbon dioxide into methyl alcohol or related oxygenates via aqueous eleetrocatalytic reduction using what can be called a regenerative fuel cell system. The direct methanol fuel cell... 

Ethylene oxide is produced by adding ethylene, oxygen, a methane diluent, and recycled carbon dioxide to a continuous reactor. Gaseous compositions are controlled carefully to keep the concentrations outside the explosion limits. 

Separator. In general, the lowest separator operating pressure and resulting operating temperature will produce the cleanest recycled carbon dioxide. Contamination carry over from the separator is a function of the contaminant vapor pressure and the separator design. Some of the contaminant that is removed from carbon dioxide in the separator will fractionate as a function its vapor pressure at... 

M.M. Halmann, Chemical Fixation of Carbon Dioxide— Methods for Recycling Carbon Dioxide into Useful Products, CRC Press, Boca Raton, FL, 1994. 

Figure 8.12 Equilibrium and operating lines for the ethanol-water-carbon dioxide system in this instance there is no ethanol in the recycled carbon dioxide.

Non-Thermal Plasma Synthesis of Formic Acid in CO2-H2O Mixture. Determine the minimum energy efficiency of the plasma-chemical HCOOH synthesis in the CO2-H2O mixture (9-60) required for effective hydrogen production in the double-step cycle (9-60) and (9-61). Assume that thermodynamically about 70% of the total energy required for hydrogen production from water should be consumed in this case for decomposition of formic acid (9-61) to form hydrogen and to recycle carbon dioxide back to the plasma process. 

Olah, George A., Alain Goeppert, and G. K. Surya Prakash. Beyond Oil and Gas. New York John Wiley Sons, 2006. This is a very accessible book describing the use of methanol in combustion fuels and fuel cells and the possibility of recycling carbon dioxide to make methanol thus reducing the greenhouse gas emission problem. 

The first successful large-scale production of a polypropylene carbonate (PPC) polymer using waste carbon dioxide (CO ) was conducted by Novomer in collaboration with specialty chemical manufacturer Albemarle Corporation (Orangeburg, SC) in May 2013 (http //energy.gov/fe/articles/recycling-carbon-dioxide-make-plastics). 

That might be a fitting twist on Nike s iconic slogan after recent announcement that it is adopting a waterless dyeing technology that uses recycled carbon dioxide to color synthetic textiles. 

When solute removal is by washing (as in Table 8.1 c and d), phase equilibria and mass transfer rate data will be required for the mixtures of the solute, and also of the near-critical solvent in the washing fluid. In particular, distribution coefficients will be required for the solute between the two phases. The water-washing of recycled carbon dioxide following decaffeination has been described in chapter 5 and is discussed in detail in two patents [1,2]. 

As we have mentioned previously, for highly exothermic reactions such as the partial oxidation of organic molecules, it is sometimes necessary to add an inert material to the reactor feed to moderate the temperature rise in the reactor and/or to move the reacting conponents outside of the explosive (flammability) limits. The most often used material for this purpose is steam, but any inert material that is available may be considered. For exanple, in the coal gasification exanple given earlier, steam is used to moderate the tenperature rise in the reactor. For the case of recycling carbon dioxide to affect the water-gas shift reaction, there is another potential benefit. The recycling of carbon dioxide reduces the amount of steam needed in the feed to the reactor, because the carbon dioxide can absorb heat and reduce the tenperature rise in the reactor. 

Moreover the characteristic of bioplastics to recycle carbon dioxide and/or to biodegrade minimising the risks of pollution can offer significant environmental and social benefits in a wide range of disposal options such as sewage sludge water treatment plants, composting, and incineration. 

M. Peters, B. Kohler, W. Kuckshinrichs, W. Leitner, P. Markewitz, T.E. Muller, Chemical technologies for exploiting and recycling carbon dioxide into the value chain, ChemSusChem 4 (2011) 1216-1240. 

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