https://www.selleckchem.com/products/2-3-cgamp.html Hydrochars are materials with a promising future, as their high carbon content and porosity renders them suitable for uses including peat substitutes, soil remediation and carbon adsorbent precursors. Combining hydrothermal carbonization and pyrolysis offers the prospect to provide advanced materials with a higher porosity and carbon content. This approach would mitigate drawbacks associated to hydrochars, including phytotoxicity. This research studied the influence of pyrolysis temperature and heating time on the resulting properties of chars made from hydrothermal carbonization of biomass wastes at 200 °C for 4 h and compared them to biochars that had not received any prior hydrothermal carbonization. Interestingly, hydrochar followed by pyrolysis was able to result in phytostimulation, while, when only pyrolysis was carried out, phytotoxicity was eliminated, but no phytostimulant effect was observed. In addition, the results indicated that the higher and longer the pyrolysis temperature (from 350 to 550 °C) and duration time (from 1 to 5 h), respectively, the more microporosity was generated, while phytotoxicity was reduced. In addition, aromaticity and thermal stability significantly increased with pyrolysis treatment. Consequently, hydrochars improve their properties and offer more potential for environmental applications after a pyrolysis post-treatment. Landfills are the third largest anthropogenic source of the greenhouse gas methane worldwide. In the upper portions of landfill covers, methane is oxidized aerobically by microorganisms to form the less-potent greenhouse gas carbon dioxide; however, because of the low permeability of oxygen, no aerobic oxidation occurs in deeper portions of the cover. Therefore, the goal of this study was to enhance anaerobic oxidation of methane (AOM) in the deeper parts of landfill covers, to increase overall methane removal, via addition of electron acceptors besides oxyge