Ash

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Wood ash Wood ash.jpg
Wood ash

Ash or ashes are the solid remnants of fires. [1] Specifically, ash refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the non-gaseous, non-liquid residue after complete combustion.

Contents

Ashes as the end product of incomplete combustion are mostly mineral, but usually still contain an amount of combustible organic or other oxidizable residues. The best-known type of ash is wood ash, as a product of wood combustion in campfires, fireplaces, etc. The darker the wood ashes, the higher the content of remaining charcoal from incomplete combustion. The ashes are of different types. Some ashes contain natural compounds that make soil fertile. Others have chemical compounds that can be toxic but may break up in soil from chemical changes and microorganism activity.

Like soap, ash is also a disinfecting agent (alkaline). [2] The World Health Organization recommends ash or sand as alternative for handwashing when soap is not available. [3]

Natural occurrence

Ash occurs naturally from any fire that burns vegetation, and may disperse in the soil to fertilise it, or clump under it for long enough to carbonise into coal.

Composition

The composition of the ash varies depending on the product burned and its origin. The "ash content" or "mineral content" of a product is derived its incineration under temperatures ranging from 150 °C (302 °F) to 900 °C (1,650 °F). [4]

Wood and plant matter

The composition of ash derived from wood and other plant matter varies based on plant species, parts of the plants (such as bark, trunk, or young branches with foliage), type of soil, and time of year. The composition of these ashes also differ greatly depending on mode of combustion.

Wood ashes, in addition to residual carbonaceous materials (unconsumed embers, activated carbons impregnated with carbonaceous particles, tars, various gases, etc.), contain a between 20% and 50% calcium in the form of calcium oxide and are generally rich in potassium carbonate. Ashes derived from grasses, and the Gramineae family in particular, are rich in silica. [5] The color of the ash comes from small proportions of inorganic minerals such as iron oxides and manganese. The oxidized metal elements that constitute wood ash are mostly considered alkaline.

For example, ash collected from wood boilers is composed of [6]

The pH of the ash is between 10 and 13, mostly due to the fact that the oxides of calcium, potassium, and sodium are strong bases. Acidic components such as carbon dioxide, phosphoric acid, silicic acid, and sulfuric acid are rarely present and, in the presence of the previously mentioned bases, are generally found in the form of salts, respectively carbonates, phosphates, silicates and sulphates.

Strictly speaking, calcium and potassium salts produce the aforementioned calcium oxide (also known as quicklime) and potassium during the combustion of organic matter. But, in practice, quicklime is only obtained via lime-kiln, and potash (from potassium carbonate) or baking soda (from sodium carbonate) is extracted from the ashes.

Other substances such as sulfur, chlorine, iron or sodium only appear in small quantities. Still others are rarely found in wood, such as aluminum, zinc, and boron. (depending on the trace elements drawn from the soil by the incinerated plants).

Mineral content in ash depends on the species of tree burned, even in the same soil conditions. More chloride is found in conifer trees than broadleaf trees, with seven times as much found in spruces than in oak trees. There is twice as much phosphoric acid in the European aspen than in oaks and twice as much magnesium in elm trees than in the Scotch pine.

Ash composition also varies by which part of the tree was burnt. Silicon and calcium salts are more abundant in bark than in wood, while potassium salts are primarily found in wood. Compositional variation also occurred based on the season in which the tree died.

Food

In food processing, mineral and ash content is used to characterize the presence of organic and inorganic components in food for monitoring quality, nutritional quantification and labeling, analyzing microbiological stability, and more. [4] This process can be used to measure minerals like calcium, sodium, potassium, and phosphorus as well as metal content such as lead, mercury, cadmium, and aluminum.

Other Properties

Shape

Size

Hardness

Incomplete combustion

Specific types

Joss paper ash. With wind and dispersion, the size of particulates decreases, while the number of particles increases. HK Sheung Wan Wing Lok Street fire burning offering papers Chinese style December 2018 IX2 02.jpg
Joss paper ash. With wind and dispersion, the size of particulates decreases, while the number of particles increases.

Cremation ashes

Cremation ashes, also called cremated remains or "cremains," are the bodily remains left from cremation. [7] They often take the form of a grey powder resembling coarse sand. While often referred to as ashes, the remains primarily consist of powdered bone fragments due to the cremation process, which eliminates the body's organic materials. [8] [9] People often store these ashes in containers like urns, although they are also sometimes buried or scattered in specific locations. [10]

Aging process

Global distillation

Health effects

Mechanism

Oxidative stress

Inflammation

Others

Health conditions

Effect on climate change

See also

Related Research Articles

In chemistry, an alkali is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The adjective alkaline, and less often, alkalescent, is commonly used in English as a synonym for basic, especially for bases soluble in water. This broad use of the term is likely to have come about because alkalis were the first bases known to obey the Arrhenius definition of a base, and they are still among the most common bases.

<span class="mw-page-title-main">Carbonate</span> Salt or ester of carbonic acid

A carbonate is a salt of carbonic acid, H2CO3, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate groupO=C(−O−)2.

<span class="mw-page-title-main">Potash</span> Salt mixture

Potash includes various mined and manufactured salts that contain potassium in water-soluble form. The name derives from pot ash, plant ashes or wood ash soaked in water in a pot, the primary means of manufacturing potash before the Industrial Era. The word potassium is derived from potash.

<span class="mw-page-title-main">Weathering</span> Deterioration of rocks and minerals through exposure to the elements

Weathering is the deterioration of rocks, soils and minerals through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs in situ, and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity.

<span class="mw-page-title-main">Sodium carbonate</span> Chemical compound

Sodium carbonate is the inorganic compound with the formula Na2CO3 and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water. Historically, it was extracted from the ashes of plants grown in sodium-rich soils, and because the ashes of these sodium-rich plants were noticeably different from ashes of wood, sodium carbonate became known as "soda ash". It is produced in large quantities from sodium chloride and limestone by the Solvay process, as well as by carbonating sodium hydroxide which is made using the Chlor-alkali process.

A period 3 element is one of the chemical elements in the third row of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases: a new row is begun when chemical behavior begins to repeat, meaning that elements with similar behavior fall into the same vertical columns. The third period contains eight elements: sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine and argon. The first two, sodium and magnesium, are members of the s-block of the periodic table, while the others are members of the p-block. All of the period 3 elements occur in nature and have at least one stable isotope.

The Leblanc process was an early industrial process for making soda ash used throughout the 19th century, named after its inventor, Nicolas Leblanc. It involved two stages: making sodium sulfate from sodium chloride, followed by reacting the sodium sulfate with coal and calcium carbonate to make sodium carbonate. The process gradually became obsolete after the development of the Solvay process.

The Solvay process or ammonia–soda process is the major industrial process for the production of sodium carbonate (soda ash, Na2CO3). The ammonia–soda process was developed into its modern form by the Belgian chemist Ernest Solvay during the 1860s. The ingredients for this are readily available and inexpensive: salt brine (from inland sources or from the sea) and limestone (from quarries). The worldwide production of soda ash in 2005 was estimated at 42 million tonnes, which is more than six kilograms (13 lb) per year for each person on Earth. Solvay-based chemical plants now produce roughly three-quarters of this supply, with the remaining being mined from natural deposits. This method superseded the Leblanc process.

ATC code A12Mineral supplements is a therapeutic subgroup of the Anatomical Therapeutic Chemical Classification System, a system of alphanumeric codes developed by the World Health Organization (WHO) for the classification of drugs and other medical products. Subgroup A12 is part of the anatomical group A Alimentary tract and metabolism.

<span class="mw-page-title-main">Water softening</span> Removing positive ions from hard water

Water softening is the removal of calcium, magnesium, and certain other metal cations in hard water. The resulting soft water requires less soap for the same cleaning effort, as soap is not wasted bonding with calcium ions. Soft water also extends the lifetime of plumbing by reducing or eliminating scale build-up in pipes and fittings. Water softening is usually achieved using lime softening or ion-exchange resins, but is increasingly being accomplished using nanofiltration or reverse osmosis membranes.

<span class="mw-page-title-main">Lime (material)</span> Calcium oxides and/or hydroxides

Lime is an inorganic material composed primarily of calcium oxides and hydroxides. It is also the name for calcium oxide which occurs as a product of coal-seam fires and in altered limestone xenoliths in volcanic ejecta. The International Mineralogical Association recognizes lime as a mineral with the chemical formula of CaO. The word lime originates with its earliest use as building mortar and has the sense of sticking or adhering.

<span class="mw-page-title-main">Organic fertilizer</span> Fertilizer developed from natural processes

Organic fertilizers are fertilizers that are naturally produced. Fertilizers are materials that can be added to soil or plants, in order to provide nutrients and sustain growth. Typical organic fertilizers include all animal waste including meat processing waste, manure, slurry, and guano; plus plant based fertilizers such as compost; and biosolids. Inorganic "organic fertilizers" include minerals and ash. The organic-mess refers to the Principles of Organic Agriculture, which determines whether a fertilizer can be used for commercial organic agriculture, not whether the fertilizer consists of organic compounds.

In analytical chemistry, ashing or ash content determination is the process of mineralization by complete combustion for preconcentration of trace substances prior to a chemical analysis, such as chromatography, or optical analysis, such as spectroscopy.

<span class="mw-page-title-main">Mineral ascorbates</span>

Mineral ascorbates are a group of salts of ascorbic acid. They are composed of a mineral cation bonded to ascorbate.

A pyrotechnic composition is a substance or mixture of substances designed to produce an effect by heat, light, sound, gas/smoke or a combination of these, as a result of non-detonative self-sustaining exothermic chemical reactions. Pyrotechnic substances do not rely on oxygen from external sources to sustain the reaction.

<span class="mw-page-title-main">Alkaline precipitation</span>

Alkaline precipitation occurs due to natural and anthropogenic causes. It happens when minerals, such as calcium, aluminum, or magnesium combine with other minerals to form alkaline residues that are emitted into the atmosphere, absorbed by water droplets in clouds, and eventually fall as rain. Aquatic environments are especially impacted by alkaline precipitation. Because alkaline precipitation can be harmful to the environment, it is important to utilize various methods such as air pollution control, solidification and stabilization, and remediation to manage it.

<span class="mw-page-title-main">Alkali soil</span> Soil type with pH > 8.5

Alkali, or Alkaline, soils are clay soils with high pH, a poor soil structure and a low infiltration capacity. Often they have a hard calcareous layer at 0.5 to 1 metre depth. Alkali soils owe their unfavorable physico-chemical properties mainly to the dominating presence of sodium carbonate, which causes the soil to swell and difficult to clarify/settle. They derive their name from the alkali metal group of elements, to which sodium belongs, and which can induce basicity. Sometimes these soils are also referred to as alkaline sodic soils. Alkaline soils are basic, but not all basic soils are alkaline.

<span class="mw-page-title-main">Wood ash</span> Residue powder left after the combustion of wood

Wood ash is the powdery residue remaining after the combustion of wood, such as burning wood in a fireplace, bonfire, or an industrial power plant. It is largely composed of calcium compounds along with other non-combustible trace elements present in the wood. It has been used for many purposes throughout history.

<span class="mw-page-title-main">Uranyl carbonate</span> Chemical compound

Uranyl carbonate refers to the inorganic compound with the formula UO2CO3. Also known by its mineral name rutherfordine, this material consists of uranyl (UO22+) and carbonate (CO32-). Like most uranyl salts, the compound is a polymeric, each uranium(VI) center being bonded to eight O atoms. Hydrolysis products of rutherfordine are also found in both the mineral and organic fractions of coal and its fly ash and is the main component of uranium in mine tailing seepage water.

References

  1. ↑ "the definition of ash". www.dictionary.com. Retrieved 2018-06-18.
  2. ↑ Howard et al. 2002: Healthy Villages A guide for communities and community health workers. CHAPTER 8 Personal, domestic and community hygiene. WHO. Accessed Oct. 2014. http://www.who.int/water_sanitation_health/hygiene/settings/hvchap8.pdf
  3. ↑ WHO 2014: Water Sanitation Health. How can personal hygiene be maintained in difficult circumstances? Accessed Oct. 2014
  4. 1 2 McClements, D. Julian. "Analysis of Ash and Minerals". Analysis of Food Products Lectures. Retrieved 2024-06-15.
  5. ↑ Pépin, Denis (2013). Composts et paillis: pour un jardin sain, facile et productif. Terre vivante. p. 54. ISBN   978-2360980918.
  6. ↑ Couturier, Christian; Brasset, Thierry. "Gestion et valorisation de cendres de chaufferies bois" [Management and recovery of wood boiler ashes](PDF) (in French). Agence de l'Environnement et de la Maîtrse de l'Energie. Archived from the original (PDF) on 2015-01-15. Retrieved 2024-06-24.
  7. ↑ "What Are Cremains? (& What to Do with Them) » Urns | Online". www.usurnsonline.com.
  8. ↑ "All About Cremation Ashes | What Are Human Ashes Made of | Scattering Ashes". www.cremationsolutions.com.
  9. ↑ "Education | Cremation ashes". www.lonite.ca.
  10. ↑ "What To Do With Cremated Remains". cremation.com. Retrieved 25 June 2023.
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