生物炭/地聚物复合膜的制备及其对四环素的去除

Preparation of biochar/geopolymer composite film and its removal of tetracycline

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H_(2)O_(2)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H_(2)O_(2)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H_(2)O_(2)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H_(2)O_(2)产生∙OH,从而实现盐酸四环素的高效降解。

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 H_(2)O_(2) 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 H_(2)O_(2) 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.