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Graphical abstract Highlights • Resolution-enhanced KMDs using fractional base units are extended to carbonaceous samples. • Mass spectra of wood and coal extracts become compositional maps with a KMD analysis. • Consecutive data processing with slicing and zooming produces informative KMD plots. • Highly confident assignments of ion series and comparison of datasets are made possible. • Improvements of the KMD-based processing are compiled into an advanced KMD toolkit. Abstract The Kendrick mass defect (KMD) analysis conveniently turns a complex high-resolution mass spectrum into a compositional map with informative clustering of points depending on the elemental composition of the associated ions. It has nevertheless been left unchanged for thirty years with the use of chemical moieties such as methylene as base units for the computation of "regular" mass defects displayed in condensed plots regardless of the samples. The concept of "resolution-enhanced" KMD analysis using the mass of the repeating unit divided by an integer as the new fractional base unit has been recently introduced for the computation of expanded plots from polymeric mass spectral data with a dramatically improved separation of ion series. This user-friendly data processing is extended to the case of carbonaceous samples for the first time with the analysis of water-insoluble organic microspheres recovered from the hydrothermal extraction of wood and coals. In a didactic discussion with illustrative examples, the direct resolution-enhanced KMD analysis, the consecutive resolution-enhanced analysis of a part of a regular KMD plot or the systematic slicing of plots in a multistep procedure are shown to produce simple resolution-enhanced KMD plots or resolution-enhanced zooming from complex mass spectra. The combination of these techniques in a unique "advanced KMD analysis" toolkit is expected to revolutionize the data processing of high-resolution mass spectra with unprecedented separating and unraveling capabilities. [ABSTRACT FROM AUTHOR]

Three brown coals were extracted by a hydrothermal method at 350 °C and 20 MPa for 90 min, and the molecular compositions of the deposit extracts were analyzed in detail by high-resolution mass spectrometry measurements. The extract yields were as high as ∼30% for all brown coals, indicating that hydrothermal extraction is applicable to brown coals with differing ash and sulfur contents. The high-resolution mass measurements with Kendrick mass analyses identified the chemical compositions and clarified the abundance of common molecular species in all the extracts prepared from the three brown coals. The sum of mass intensities of overlapped C n H m , C n H m O, C n H m O 2 , C n H m O 3 , C n H m O 4 , and C n H m N species in the mass spectra of LY, NM, and YN extracts were 37.0%, 35.9%, and 50.8%, respectively, indicating the presence of abundant compounds with similar molecular compositions in all of the extracts, regardless of the parent coal. [ABSTRACT FROM AUTHOR]

Abstract: A novel coal conversion process was proposed: the method combines “a hydrothermal extraction of brown coal (HT-Extraction)” and “a catalytic hydrothermal gasification of the extract (CHT-Gasification)” both of which are performed under the exactly same conditions of less than 350°C and less than 20MPa. Organic compounds in the aqueous phase, extracted from brown coal, was gasified using a novel Ni-supported carbon catalyst developed by the authors, producing combustible gas rich in CH4 and H2. Through this process performed at 350°C and 18MPa, an Australian brown coal was almost perfectly converted into 53% of upgraded coal, 23% of methane, and 24% of carbon dioxide on carbon basis. Simultaneously, 4.4mol of hydrogen was generated from 100mol of carbon of the coal. This process transferred 97% of energy involved in the raw coal to the products, indicating its effectiveness. [Copyright &y& Elsevier]