Calcination in the context of Volatility (chemistry)

Bone china is a type of vitreous, translucent pottery, the raw materials for which include bone ash, feldspathic material and kaolin. It has been defined as "ware with a translucent body" containing a minimum of 30% of phosphate derived from calcined animal bone or calcium phosphate. Bone china is amongst the strongest of whiteware ceramics, and is known for its high levels of whiteness and translucency. Its high strength allows it to be produced in thinner cross-sections than other types of whiteware. Like stoneware, it is vitrified, but is translucent due to differing mineral properties.

In the mid-18th century, English potters had not succeeded in making hard-paste porcelain (as made in East Asia and Meissen porcelain), but found bone ash a useful addition to their soft-paste porcelain mixtures. This became standard at the Bow porcelain factory in London (operating from around 1747), and spread to some other English factories. The modern product was developed by the Staffordshire potter Josiah Spode in the early 1790s. Spode included kaolin, so his formula, sometimes called "Staffordshire bone-porcelain", was effectively hard-paste, but stronger, and versions were adopted by all the major English factories by around 1815.

Bone ash is a white material produced by the calcination of bones. Typical bone ash consists of about 55.82% calcium oxide, 42.39% phosphorus pentoxide, and 1.79% water. The exact composition of these compounds varies depending upon the type of bones being used, but generally the formula for bone ash is Ca₅(OH)(PO₄)₃. Bone ash usually has a density around 3.10 g/mL and a melting point of 1670 °C (3038 °F). Most bones retain their cellular structure through calcination.

A frit is a ceramic composition that has been fused, quenched, and granulated. Frits form an important part of the batches used in compounding enamels and ceramic glazes; the purpose of this pre-fusion is to render any soluble and/or toxic components insoluble by causing them to combine with silica and other added oxides.However, not all glass that is fused and quenched in water is frit, as this method of cooling down very hot glass is also widely used in glass manufacture.

According to the OED, the origin of the word "frit" dates back to 1662 and is "a calcinated (Calcination) mixture of sand and fluxes ready to be melted in a crucible to make glass". Nowadays, the unheated raw materials of glass making are more commonly called "glass batch".

A rotary kiln is a pyroprocessing device used to raise materials to a high temperature (calcination) in a continuous process. Materials produced using rotary kilns include:

• Cement
• Lime
• Refractories
• Metakaolin
• Titanium dioxide
• Alumina
• Vermiculite
• Iron ore pellets
• Incineration of biomedical waste
• process like pyrolysis {with without passing hot gases}

They are also used for roasting a wide variety of sulfide ores prior to metal extraction.

Pyroprocessing (from Greek Πυρος = fire) is a process in which materials are subjected to high temperatures (typically over 800 °C) in order to bring about a chemical or physical change. Pyroprocessing includes such terms as ore-roasting, calcination and sintering. Equipment for pyroprocessing includes kilns, electric arc furnaces and reverberatory furnaces.

Cement manufacturing is a very common example of pyroprocessing. The raw material mix (raw meal) is fed to a kiln where pyroprocessing takes place. As with most industries, pyroprocessing is the most energy-intensive part of the industrial process.

Petroleum coke, abbreviated coke, pet coke or petcoke, is a final carbon-rich solid material that derives from oil refining, and is one type of the group of fuels referred to as cokes. Petcoke is the coke that, in particular, derives from a final cracking process—a thermo-based chemical engineering process that splits long chain hydrocarbons of petroleum into shorter chains—that takes place in units termed coker units. (Other types of coke are derived from coal.) Stated succinctly, coke is the "carbonization product of high-boiling hydrocarbon fractions obtained in petroleum processing (heavy residues)". Petcoke is also produced in the production of synthetic crude oil (syncrude) from bitumen extracted from Canada's oil sands and from Venezuela's Orinoco oil sands.In petroleum coker units, residual oils from other distillation processes used in petroleum refining are treated at a high temperature and pressure leaving the petcoke after driving off gases and volatiles, and separating off remaining light and heavy oils. These processes are termed "coking processes", and most typically employ chemical engineering plant operations for the specific process of delayed coking.

This coke can either be fuel grade (high in sulfur and metals) or anode grade (low in sulfur and metals). The raw coke directly out of the coker is often referred to as green coke. In this context, "green" means unprocessed. The further processing of green coke by calcining in a rotary kiln removes residual volatile hydrocarbons from the coke. The calcined petroleum coke can be further processed in an anode baking oven to produce anode coke of the desired shape and physical properties. The anodes are mainly used in the aluminium and steel industry.

A lime kiln is a kiln used for the calcination of limestone (calcium carbonate) to produce the form of lime called quicklime (calcium oxide). The chemical equation for this reaction is: CaCO₃ + heat → CaO + CO₂

This reaction can take place at anywhere above 840 °C (1,540 °F), but is generally considered to occur at 900 °C (1,650 °F) (at which temperature the partial pressure of CO₂ is 1 atmosphere), but a temperature around 1,000 °C (1,830 °F) (at which temperature the partial pressure of CO₂ is 3.8 atmospheres) is usually used to make the reaction proceed quickly. Excessive temperature is avoided because it produces unreactive, "dead-burned" lime.