Effects of atmospheric ageing under different temperatures on surface properties of sludge-derived biochar and metal/metalloid stabilization

Biochar Aging: Mechanisms, Physicochemical Changes, Assessment, And Implications for Field Applications

“…Atmospheric oxygen-induced oxidation can introduce additional oxygen-containing functional groups, such as hydroxyl, carbonyl, and carboxyl, to the biochar surface. This mild oxidation process is slow at ambient temperature . For instance, atmospheric aging of sludge biochar for 2 months could only increase the amount of oxygen-containing functional groups by 2% (incubation temperature 45 °C, measured by the Boehm titration method) .…”

Thallium contamination in agricultural soils and associated potential remediation via biochar utilization

“…Specifically, Tl can be rapidly immobilized by the applied biochar in agricultural soils, and this mitigates the plant uptake of Tl. Practically, biochar can be aged while entering into agricultural soils, thereby affecting the remediation of Tl, which can be affected by ambient (micro) organisms and many corresponding factors including clay minerals, pH, and organic matter (Li et al 2018a, Wang et al 2017a, b, Yue et al 2019, Zama et al 2018. Additionally, biochar exhibits a bulk density that is significantly lower than that of mineral soil and can decrease the majority density of the soil (Tack and Egene 2019), and thus the minerals which include phosphate and carbonates present in biochar can reduce the mobility and bioavailability of Tl in soil via a precipitation method among salts and Tl .…”

Biochar-cadmium retention and its effects after aging with Hydrogen Peroxide (H2O2)

“…The reported results show that when biochar ages it usually becomes more acidic ( Cheng and Lehmann 2009 ; Zhao et al., 2015 ), increasing the CEC and number of oxygenated surface functional groups (e.g. carboxylic acids) ( Yao et al., 2010 ), while lowering surface area and aliphatic C ( Ghaffar et al., 2015 ; Wang et al., 2017 ).…”

“…Research methods for studying aging effects on biochars include: composting ( Wiedner et al., 2015 ), incubations ( Mukome et al., 2014 ; Singh et al., 2016 ), field ( Khorram et al., 2017 ; Mukherjee et al., 2014 ; Ren et al., 2018 ), application of dry-wet and freeze-thaw cycles ( Xu et al., 2018 ), application of hot air ( Wang et al., 2017 ), acid leaching with HNO 3 /H 2 SO 4 ( Hadjittofi et al., 2014 ; Lu et al., 2015 ; Qian et al., 2015 ), and alkaline leaching with KOH ( Goswami et al., 2016 ; Jin et al., 2014 ; Petrović et al., 2016 ), NaOH ( Pietrzak et al., 2014 ) or H 2 O 2 ( Huff and Lee 2016 ; Lawrinenko et al., 2016 ; Mia et al., 2017b ; Xue et al., 2012 ; Zuo et al., 2016 ). We only found one research paper with the specific focus on evaluating how Cd adsorption changes after aging with H 2 O 2 .…”