A novel green approach for the synthesis of binder-free zeolite NaX foams by joint utilization of metakaolin and clinoptilolite as Si-Al precursors - Luowen Xiang; Qiancheng Qiao; Xiumei Qiu; Sen Zhou; Hongquan Wang; Xiaoyan Zhu; Chunjie Yan; Yi Liu (Applied Clay Science, 2026)