The present study examined the effect of pyrolysis temperature on the physicochemical properties of biochar, activation process and carbon capture. Two different categories of biochars were synthesized from herbaceous (miscanthus and switchgrass) and agro-industrial (corn stover and sugarcane bagasse) feedstock under four different pyrolysis temperatures −500, 600, 700, and 800°C. The synthesized biochars underwent sono-amination activation comprising low-frequency acoustic treatment followed by amine functionalization to prepare adsorbents for CO₂ capture. The highest increment (200%) of CO₂ capture capacity was observed for sono-aminated samples prepared at 600 and 700°C (maximum improvement for miscanthus), while biochars synthesized at 500 and 800°C demonstrated comparatively lesser increment in adsorption capacities that falls in the range of 115–151 and 127–159%, respectively compared to 600 and 700°C. The elevated pyrolysis temperature (particularly 600 and 700°C) resulted in increased %C and %ash contents and reduced %N contents with enhancement of micro surface area and pore volume. Thus, the superior adsorption capacity of miscanthus (at 600 and 700°C) can be attributed to their large surface areas (303–325 m²/g), high carbon contents (82–84%), and low ash contents (4–5%), as well as %N contents after sono-amination that was twice that of raw char.

本研究检查了热解温度对生物炭的理化性质，活化过程和碳捕获的影响。在-500、600、700和800°C的四种不同热解温度下，从草食（芒草和柳枝））和农用工业（玉米秸秆和甘蔗渣）原料合成了两种不同类型的生物炭。对合成的生物炭进行声波胺化活化处理，包括低频声学处理，然后进行胺官能化，以制备用于CO ₂捕获的吸附剂。CO ₂的最高增量（200％）在600和700°C制备的声胺化样品观察到捕获能力（对芒草的最大改善），而在500和800°C合成的生物炭显示出相对较小的吸附能力增量，范围在115–151和127之间–600％和700°C分别为–159％。较高的热解温度（特别是600和700°C）导致％C和％灰分含量增加以及％N含量减少，同时微表面积和孔体积增加。因此，由于具有较大的表面积（303-325 m ² / g），高碳含量（82-84％）和低灰分含量（4），所以对金莲花具有较高的吸附能力（在600和700°C时）。–5％），以及经过声胺化处理后的％N含量是原炭的两倍。