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.

碳氢化合物是具有前途的材料，因为其高碳含量和高孔隙率使其适合用于泥炭替代品，土壤修复和碳吸附剂前体。水热碳化和热解的结合提供了提供具有更高孔隙率和碳含量的先进材料的前景。这种方法将减轻与水焦有关的缺点，包括植物毒性。这项研究研究了热解温度和加热时间对生物质废物在200°C进行水热碳化4小时制得的炭的最终性能的影响，并将其与之前未进行过任何水热碳化的生物炭进行了比较。有趣的是，先进行热解后再进行炭化可以刺激植物，而仅进行热解时，消除了植物毒性，但未观察到植物刺激作用。此外，结果表明热解温度（从350到550°C）和持续时间（从1到5 h）分别越高和越长，产生的微孔越多，而植物毒性降低了。另外，通过热解处理，芳香性和热稳定性显着提高。因此，在进行热解后处理后，水炭改善了其性能并为环境应用提供了更大的潜力。热解处理后，芳香性和热稳定性显着提高。因此，在进行热解后处理后，水炭改善了其性能并为环境应用提供了更大的潜力。热解处理后，芳香性和热稳定性显着提高。因此，在进行热解后处理后，水炭改善了其性能并为环境应用提供了更大的潜力。