Abstract:

A low-cost, easy-to-recycle, green and pollution-free biochar/geopolymer composite film (BC/GM) was prepared by in-situ synchronous carbonization and self-activation with alkali lignin, metakaolin and slag for the catalytic degradation of tetracycline antibiotics in water. The morphology and physical and chemical properties of BC/GM were analyzed by SEM, XRD, FTIR and XPS. The effects of water glass modulus, alkali lignin content and calcination temperature on the degradation efficiency of tetracycline hydrochloride by H₂O₂ were investigated. The results showed that the geopolymer inorganic film (GM) not only acted as a porous carrier to facilitate the recycling of biochar and prevent the biomass precursors from direct carbonization and coking , but also helped to realize synchronous self-activation of alkali lignin precursor in the process of in-situ carbonization. When the water glass modulus was 1.2, the removal rate of alkali lignin was 0.2mL and the calcination temperature was 600℃, the removal rate of H₂O₂ catalyzed degradation of tetracycline hydrochloride by BC/GM reaches 92.55%, which was 40% higher than that of biochar. The graphitized carbon in BC/GM had a porous structure, which contributes to the generation of ?OH, and eventually realized the efficient degradation of tetracycline hydrochloride.

Key words: biochar, geopolymer, tetracycline hydrochloride, catalytic degradation, deactivation

摘要：

以碱木质素、偏高岭土、矿渣为原料，通过原位炭化同步自活化的方法制备了一种低成本、易回收、绿色无污染的生物炭/地聚物复合膜（BC/GM）用于催化H₂O₂产生?OH以降解水中的四环素。通过SEM、XRD、FTIR、XPS等一系列的表征手段分析了BC/GM的形貌结构和理化性质，并且探究了水玻璃模数、碱木质素溶液添加量、煅烧温度对BC/GM催化H₂O₂降解盐酸四环素效率的影响。结果表明，地聚物无机膜（GM）不仅充当了一种便于生物炭回收利用的多孔载体，防止生物质前体直接炭化结焦，而且有助于碱木质素前体在原位炭化过程中实现同步自活化；在水玻璃模数为1.2、碱木质素溶液添加量为0.2 mL、煅烧温度为600℃时，BC/GM催化H₂O₂降解盐酸四环素的去除率达到了92.55%，比纯生物炭作为催化剂时提升了近40%。BC/GM具有更高的比表面积和更丰富的含氧官能团，有助于催化H₂O₂产生?OH，从而实现盐酸四环素的高效降解。

关键词: 生物炭, 地质聚合物, 盐酸四环素, 催化降解, 失活