Carbon dioxide solvents such as organochlorides. It is used by some dry cleaners for this reason (see green chemistry). It is used in the preparation of some aerogels because of the properties of supercritical carbon dioxide. Plants require carbon dioxide to conduct photosynthesis. The atmospheres of greenhouses may (if of large size, must) be enriched with additional to sustain and increase the rate of plant growth. At very high concentrations (100 times atmospheric concentration, or greater), carbon dioxide can be toxic to animal life, so raising the concentration to 10,000 ppm (1%) or higher for several hours will eliminate pests such as
Carbon dioxide removal funded by Bill Gates, is developing a process to capture carbon dioxide using a solution of potassium hydroxide mixed with some water at their pilot plant. They hope to create and sell synthetic fuels at a cost of $100 a ton. Among the technologies studied for direct air capture (DAC), the use of aqueous hydroxide sorbents is one of the most promising approaches. In this process, CO from the air is chemically dissolved into NaOH(aq) solution as NaCO; the NaCO is then reacted with solid Ca(OH), which regenerates the solvent and produces CaCO crystals; lastly, heat is applied to the