Currently, the demand for activated carbon (AC) has been growing thanks to its adsorption capacity to remove liquid and gaseous pollutants. Lignin is a biomass derived from an abundant renewable resource, rich in carbon, with potential applications in modern society. This work seeks to add greater value for the lignin, transforming it in AC and also to demonstrate the microwave pyrolysis effectiveness. ACs were obtained from Kraft lignin treated with different proportions of phosphoric acid in two different periods of time, using microwave pyrolysis in oxidizing atmosphere. The results of Fourier transform infrared spectroscopy and X-ray diffraction showed that the conversion of lignin to carbon material occurred successfully. The morphology of lignin, observed by scanning electron microscopy, showed a globular appearance and different diameters, which was converted into AC with very porous structures. Adsorption/desorption of N₂ (BET) analyses showed that the AC presented high surface areas, between 635 and 1055 m²g^-1, with the presence of micro and mesopores. The highest acid:lignin weight ratio favored higher values of AC surface area and pore volume. The maximum adsorption capacity of prepared AC was tested with methylene blue dye (MB) and amoxicillin (AMOX), and values of 140 and 220 mgg⁻¹ were found, respectively. In the case of MB, the adsorption mechanism adjusted better to the Langmuir model and the AMOX to the Freundlich model.

目前，由于活性炭去除液体和气体污染物的吸附能力，对活性炭的需求一直在增长。木质素是一种源自丰富的可再生资源的生物质，富含碳，在现代社会中具有潜在应用。这项工作旨在为木质素增加更大的价值，将其转化为 AC，并证明微波热解的有效性。活性炭是从硫酸盐木质素中获得的，在两个不同的时间段内用不同比例的磷酸处理，在氧化气氛中使用微波热解。傅里叶变换红外光谱和X射线衍射结果表明木质素向碳材料的转化成功。扫描电镜观察木质素形态呈球形，直径不同，它被转换成具有非常多孔结构的交流电。N的吸附/解吸_{图 2} (BET) 分析表明，AC 具有高表面积，介于 635 和 1055 m ² g ^{-1 之间}，存在微孔和中孔。最高的酸：木质素重量比有利于 AC 表面积和孔体积的更高值。用亚甲蓝染料 (MB) 和阿莫西林 (AMOX) 测试制备的活性炭的最大吸附容量，分别发现值为 140 和 220 mgg ^-1。在 MB 的情况下，吸附机制更好地适应 Langmuir 模型和 AMOX 更好地适应 Freundlich 模型。