건강 ≫ 원료 ≫ Water ≫ 물의 역할

이산화탄소 CO2

괴담과 괴담 패러디
- 죽음의 물질 : 일산화이수소
- 가장 은밀히 가장 많이 사용되는 합성보존료 hexuronic acid
- 중독의 물질 메틸화잔틴
- 인류의 생존을 위협하는 물질 CO2
- 죽음의 집행자 Ca
- 엄마의 독성, 모유는 불량품?

이 식품첨가물로 인한 사망사고는 끝임이 없다.

최근에도 청춘남녀가 이 첨가물로 자살을 했다. 선진국에서는 이물질의 농도를 최대 5천PPM을 상한선으로 두고 관리하는 이유는 그보다 높으면 피로, 두통, 어지럼증, 심박수 증가가 나타날 수 있으며 5만PPM에 이르면 의식을 잃고 8만PPM에 이르면 사망에 이르게 되기 때문이다. 어떤 사람이던 이 물질의 농도가 5만PPM이 넘는 공간에 들어가면 호흡 몇 번 하는 것으로도 의식을 잃을 수 있다. 일단 의식을 잃으면 스스로 깨어나지 못하고 사망에 이르기 쉽다.
그런데 이물질은 무미 무취 무색이라 소량을 집어넣으면 그 존재를 알기 힘들다. 누군가 몰래 넣어도 알기 힘들다는 뜻이다.
이것은 부식성이 있다. 그래서 암석 특히 석회암도 쉽게 구멍을 낸다. 지하 땅속에 존재하는 거대한 동굴 중에 많은 것들이 이 물질의 부식성 때문에 만들어진 것이다. 하지만 이런 부식성보다 훨씬 심각한 것은 바다 속 생태계에 미치는 영향이다. 이 물질은 다른 기체보다 훨씬 물에 용해도가 높은데, 바다 속으로 들어갈수록 농도가 높아서 강력한 부식성을 나타낸다는 것이다. 지금도 위험하지만 갈수록 이물질의 오남용에 의한 농도의 증가로 조만간 바다 속 깊은 곳의 생태계가 완전히 파괴될 가능성도 높다.
그리고 이물질은 화학공업에서 폭넓게 쓰인다. 암모니아를 합성하거나 에틸렌을 만들 때 등 수많은 화학물질의 제조에 이 물질이 쓰이며 화학 반응의 결과로 생기기도 한다. 석유의 끈적이는 타르물질을 분해할 때도 생긴다. 이렇게 생긴 부산물을 일부 회사는 비용을 들여 폐기하는 대신에 탱크로리에 담아 원예업자, 농부 등에 판매하기도 한다. 큰 수익은 아니지만 다른 기체에 비해 무책무취이고 별다른 안전조치를 취하지 않아도 되기 때문이다.
그런데 이물질이 식품첨가물로 허용이 되어있기에 많은 식품회사가 사용한다. 이것이 있으면 치즈, 육류, 소시지처럼 부패하기 쉬운 음식의 부패가 억제된다. 또 알카리성을 중화하는데도 쓰고, 니코틴이나 카페인을 추출하는데도 쓴다. 비극성이라 액체 상태에서는 기름이나 지용성 성분을 녹이는데 효과적이기 때문이다. 그래서 이것을 이용한 세탁방식이 개발되기도 하였다. 그리고 고체인 이물질을 오래 만지면 심각한 피부 및 장기 손상을 있다.
하지만 이런 것들은 음료산업에 쓰이는 것에 비하면 새발의 피다. 많은 사람의 타도의 대상인 탄산음료치고 이것이 안 들어간 제품은 없다. 탄산음료 1병에는 병부피의 2~3배 정도 부피의 이 물질이 들어있다. 그래서 고온에 넣거나 냉동고에 넣으면 폭발을 할 수도 있다. 고압의 특수한 설비를 통해 워낙 많은 양을 주입하였기 때문이다
5만PPM이면 우리의 생명을 위협하는 이 물질을 우리는 여러 가지 가공식품을 통해 매일 조금씩 섭취하고 있는 것이다. 정말 끔찍한 일이 아닌가
우리는 하루바삐 이 물질의 소비를 줄여야 한다. 그것을 위해 세상에 정말 많은 사람이 노력하고 있지만 그 소비는 꾸준히 늘고 있다. 지금 인류를 위협하는 최대의 위협중의 하나이다

그런대도 아무런 사용제한이 없는 식품첨가물이다 (식품첨가물 화학적 합성품 187번)
식품첨가물 화학적 합성품 187번

이 물질의 이름은 이산화탄소이다

▶ Precursor to chemicals

In the chemical industry, carbon dioxide is mainly consumed as an ingredient in the production of urea and methanol.[citation needed] Metal carbonates and bicarbonates, as well as some carboxylic acids derivatives (e.g., sodium salicylate) are prepared using CO2.[citation needed]
In addition to conventional processes using CO2 for chemical production electrochemical methods are also being explored at a research level. In particular, the use of renewable energy for production of fuels from CO2 (such as methanol) is attractive as this could result in fuels that could be easily transported and used within conventional combustion technologies but have no net CO2 emissions.[20]

▶ Foods
Carbon dioxide is a food additive used as a propellant and acidity regulator in the food industry. It is approved for usage in the EU[21] (listed as E number E290), USA[22] and Australia and New Zealand[23] (listed by its INS number 290).
A candy called Pop Rocks is pressurized with carbon dioxide gas at about 4 x 106 Pa (40 bar, 580 psi). When placed in the mouth, it dissolves (just like other hard candy) and releases the gas bubbles with an audible pop.
Leavening agents cause dough to rise by producing carbon dioxide. Baker's yeast produces carbon dioxide by fermentation of sugars within the dough, while chemical leaveners such as baking powder and baking soda release carbon dioxide when heated or if exposed to acids.

▶ Beverages
Carbon dioxide is used to produce carbonated soft drinks and soda water. Traditionally, the carbonation in beer and sparkling wine came about through natural fermentation, but many manufacturers carbonate these drinks with carbon dioxide recovered from the fermentation process. In the case of bottled and kegged beer, the most common method used is carbonation with recycled carbon dioxide. With the exception of British Real Ale, draught beer is usually transferred from kegs in a cold room or cellar to dispensing taps on the bar using pressurized carbon dioxide, sometimes mixed with nitrogen.

▶ Wine making
Carbon dioxide in the form of dry ice is often used in the wine making process to cool down bunches of grapes quickly after picking to help prevent spontaneous fermentation by wild yeast. The main advantage of using dry ice over regular water ice is that it cools the grapes without adding any additional water that may decrease the sugar concentration in the grape must, and therefore also decrease the alcohol concentration in the finished wine.
Dry ice is also used during the cold soak phase of the wine making process to keep grapes cool. The carbon dioxide gas that results from the sublimation of the dry ice tends to settle to the bottom of tanks because it is denser than air. The settled carbon dioxide gas creates a hypoxic environment which helps to prevent bacteria from growing on the grapes until it is time to start the fermentation with the desired strain of yeast.
Carbon dioxide is also used to create a hypoxic environment for carbonic maceration, the process used to produce Beaujolais wine.
Carbon dioxide is sometimes used to top up wine bottles or other storage vessels such as barrels to prevent oxidation, though it has the problem that it can dissolve into the wine, making a previously still wine slightly fizzy. For this reason, other gases such as nitrogen or argon are preferred for this process by professional wine makers.

▶ Inert gas
It is one of the most commonly used compressed gases for pneumatic (pressurized gas) systems in portable pressure tools. Carbon dioxide is also used as an atmosphere for welding, although in the welding arc, it reacts to oxidize most metals. Use in the automotive industry is common despite significant evidence that welds made in carbon dioxide are more brittle than those made in more inert atmospheres, and that such weld joints deteriorate over time because of the formation of carbonic acid. It is used as a welding gas primarily because it is much less expensive than more inert gases such as argon or helium. When used for MIG welding, CO2 use is sometimes referred to as MAG welding, for Metal Active Gas, as CO2 can react at these high temperatures. It tends to produce a hotter puddle than truly inert atmospheres, improving the flow characteristics. Although, this may be due to atmospheric reactions occurring at the puddle site. This is usually the opposite of the desired effect when welding, as it tends to embrittle the site, but may not be a problem for general mild steel welding, where ultimate ductility is not a major concern.
It is used in many consumer products that require pressurized gas because it is inexpensive and nonflammable, and because it undergoes a phase transition from gas to liquid at room temperature at an attainable pressure of approximately 60 bar (870 psi, 59 atm), allowing far more carbon dioxide to fit in a given container than otherwise would. Life jackets often contain canisters of pressured carbon dioxide for quick inflation. Aluminium capsules of CO2 are also sold as supplies of compressed gas for airguns, paintball markers, inflating bicycle tires, and for making carbonated water. Rapid vaporization of liquid carbon dioxide is used for blasting in coal mines. High concentrations of carbon dioxide can also be used to kill pests. Liquid carbon dioxide is used in supercritical drying of some food products and technological materials, in the preparation of specimens for scanning electron microscopy and in the decaffeination of coffee beans.

▶  Fire extinguisher

Carbon dioxide extinguishes flames, and some fire extinguishers, especially those designed for electrical fires, contain liquid carbon dioxide under pressure. Carbon dioxide extinguishers work well on small flammable liquid and electrical fires, but not on ordinary combustible fires, because although it excludes oxygen, it does not cool the burning substances significantly and when the carbon dioxide disperses they are free to catch fire upon exposure to atmospheric oxygen. Carbon dioxide has also been widely used as an extinguishing agent in fixed fire protection systems for local application of specific hazards and total flooding of a protected space.[24] International Maritime Organization standards also recognize carbon dioxide systems for fire protection of ship holds and engine rooms. Carbon dioxide based fire protection systems have been linked to several deaths, because it can cause suffocation in sufficiently high concentrations. A review of CO2 systems identified 51 incidents between 1975 and the date of the report, causing 72 deaths and 145 injuries.

▶ Supercritical CO2 as solvent[edit]
Liquid carbon dioxide is a good solvent for many lipophilic organic compounds and is used to remove caffeine from coffee. Carbon dioxide has attracted attention in the pharmaceutical and other chemical processing industries as a less toxic alternative to more traditional 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.

▶ Agricultural and biological applications
Plants require carbon dioxide to conduct photosynthesis. Greenhouses may (if of large size, must) enrich their atmospheres with additional CO2 to sustain and increase plant growth.[26][27] A photosynthesis-related drop (by a factor less than two) in carbon dioxide concentration in a greenhouse compartment would kill green plants, or, at least, completely stop their 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 whiteflies and spider mites in a greenhouse.[28] Carbon dioxide is used in greenhouses as the main carbon source for Spirulina algae.[citation needed]
In medicine, up to 5% carbon dioxide (130 times atmospheric concentration) is added to oxygen for stimulation of breathing after apnea and to stabilize the O
2/CO 2 balance in blood.
It has been proposed that carbon dioxide from power generation be bubbled into ponds to grow algae that could then be converted into biodiesel fuel.[29]

▶ Oil recovery
Carbon dioxide is used in enhanced oil recovery where it is injected into or adjacent to producing oil wells, usually under supercritical conditions, when it becomes miscible with the oil. This approach can increase original oil recovery by reducing residual oil saturation by between 7 per cent to 23 per cent additional to primary extraction.[30] It acts as both a pressurizing agent and, when dissolved into the underground crude oil, significantly reduces its viscosity, and changing surface chemistry enabling the oil to flow more rapidly through the reservoir to the removal well.[31] In mature oil fields, extensive pipe networks are used to carry the carbon dioxide to the injection points.

▶ Bio transformation into fuel[edit]
Researchers have genetically modified a strain of the cyanobacterium Synechococcus elongatus to produce the fuels isobutyraldehyde and isobutanol from CO2 using photosynthesis.[32]

▶ Refrigerant[edit]
Comparison of phase diagrams of carbon dioxide (red) and water (blue) as a log-lin chart with phase transitions points at 1 atmosphere
Liquid and solid carbon dioxide are important refrigerants, especially in the food industry, where they are employed during the transportation and storage of ice cream and other frozen foods. Solid carbon dioxide is called "dry ice" and is used for small shipments where refrigeration equipment is not practical. Solid carbon dioxide is always below −78.5 °C at regular atmospheric pressure, regardless of the air temperature.
Liquid carbon dioxide (industry nomenclature R744 or R-744) was used as a refrigerant prior to the discovery of R-12 and may enjoy a renaissance due to the fact that R134a contributes to climate change. Its physical properties are highly favorable for cooling, refrigeration, and heating purposes, having a high volumetric cooling capacity. Due to its operation at pressures of up to 130 bar (1880 psi), CO2 systems require highly resistant components that have already been developed for mass production in many sectors. In automobile air conditioning, in more than 90% of all driving conditions for latitudes higher than 50°, R744 operates more efficiently than systems using R134a. Its environmental advantages (GWP of 1, non-ozone depleting, non-toxic, non-flammable) could make it the future working fluid to replace current HFCs in cars, supermarkets, and heat pump water heaters, among others. Coca-Cola has fielded CO2-based beverage coolers and the U.S. Army is interested in CO2 refrigeration and heating technology.[33][34]
The global automobile industry is expected to decide on the next-generation refrigerant in car air conditioning. CO2 is one discussed option.(see Sustainable automotive air conditioning)

▶ Coal bed methane recovery[edit]

In enhanced coal bed methane recovery, carbon dioxide would be pumped into the coal seam to displace methane, as opposed to current methods which primarily rely on the removal of water (to reduce pressure) to make the coal seam release its trapped methane.[35]

▶ Niche uses[edit]

A carbon dioxide laser.
Carbon dioxide is so inexpensive and so innocuous, that it finds many small uses that represent what might be called niche uses. For example it is used in the carbon dioxide laser, which is one of the earliest type of lasers.

Carbon dioxide can be used as a means of controlling the pH of swimming pools, by continuously adding gas to the water, thus keeping the pH level from rising. Among the advantages of this is the avoidance of handling (more hazardous) acids. Similarly, it is also used in the maintaining reef aquaria, where it is commonly used in calcium reactors to temporarily lower the pH of water being passed over calcium carbonate in order to allow the calcium carbonate to dissolve into the water more freely where it is used by some corals to build their skeleton. It is also used as the primary coolant in advanced gas-cooled reactors in the nuclear power generation industry.

Carbon dioxide induction is commonly used for the euthanasia of laboratory research animals. Methods to administer CO2 include placing animals directly into a closed, prefilled chamber containing CO2, or exposure to a gradually increasing concentration of CO2. In 2013, the American Veterinary Medical Association issued new guidelines for carbon dioxide induction, stating that a flow rate of 10% to 30% volume/min is optimal for the humane euthanization of small rodents.[36]