English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Potassium catalyzed isothermal coal hydrogasification was investigated, as an alternative route for synthetic natural gas production. Potassium chemisorption occurred on oxygen sites in the coal structure and was strongly affected by the solution pH and followed the Cation Exchange Capability (CEC) which is also pH-dependent. A quadratic function described the relation between the solution pH and the fraction of the chemisorbed potassium, while; the cumulative distribution function of two Weibull probability density functions correlated the solution pH with the CEC that was linearly correlated with the fraction of the chemisorbed potassium. Coal hydrogasification is strongly affected by the increased alkalinity of the impregnating solution and increased methane yields were obtained while carbon conversion was slightly affected. This was attributed to the formation of profuse K +  substituted active sites that decompose under H 2  attacks and trigger scission of the aromatic rings followed by K +  migration to neighboring complexes, thus, the hydrogasification reaction continuous to yield CH 4 , as codified in a three stage reaction mechanism. The relative specific hydrogasification rate was found to increase linearly with the CEC of the coal samples, suggesting that the oxygen functional groups, on which potassium is chemisorbed, act as “active sites” and are linked with the carbon’s reactivity.

Potassium catalyzed hydrogasification of low-rank coal for synthetic natural gas production