Carbonaceous in the context of Molecular weight

Soot (/sʊt/ suut) is a mass of impure carbon particles resulting from the incomplete combustion of hydrocarbons. Soot is considered a hazardous substance with carcinogenic properties. Most broadly, the term includes all the particulate matter produced by this process, including black carbon and residual pyrolysed fuel particles such as coal, cenospheres, charred wood, and petroleum coke classified as cokes or char. It can include polycyclic aromatic hydrocarbons and heavy metals like mercury.

Soot causes various types of cancer and lung disease.

Gasification is a process that converts biomass- or fossil fuel-based carbonaceous materials into gases, including as the largest fractions: dinitrogen (N₂), carbon monoxide (CO), dihydrogen (H₂), and carbon dioxide (CO₂). This is achieved by reacting the feedstock material at high temperatures (typically >700 °C), without combustion, via controlling the amount of oxygen and/or steam present in the reaction. The resulting gas mixture is called syngas (from synthesis gas) or producer gas and is itself a fuel due to the flammability of the H₂ and CO of which the gas is largely composed. Power can be derived from the subsequent combustion of the resultant gas, and is considered to be a source of renewable energy if the gasified compounds were obtained from biomass feedstock.

An advantage of gasification is that syngas can be more efficient than direct combustion of the original feedstock material because it can be combusted at higher temperatures so that the thermodynamic upper limit to the efficiency defined by Carnot's rule is higher. Syngas may also be used as the hydrogen source in fuel cells, however, the syngas produced by most gasification systems requires additional processing and reforming to remove the contaminants and other gases such as CO and CO₂ to be suitable for low-temperature fuel cell use, but high-temperature solid oxide fuel cells are capable of directly accepting mixtures of H₂, CO, CO₂, steam, and methane.

Spent shale or spent oil shale (also known as retorted shale) is a solid residue from the shale-oil extraction process of producing synthetic shale oil from oil shale. It consists of inorganic compounds (minerals) and remaining organic matter known as char—a carbonaceous residue formed from kerogen. Depending on the extraction process and the amount of remaining organic matter, spent shale may be classified as oil shale coke, semi-coke, or coke-ash residue, known also as oil shale ash. According to the European Union waste list, all these types of spent shale are classified as hazardous waste.

Oil shale coke is created by chamber ovens which were used for oil shale gas production. Vertical retorts create mainly semi-coke. Most solid heat-carrier processes create coke-ash residue, as the semi-coke created during the process is combusted for the process's energy needs.