（中國建筑材料科學研究總院有限公司 綠色建筑材料國家重點實驗室，北京 100024）
摘要：針對室內甲醛污染問題，利用礦物涂層的多孔性，對甲醛進行吸附處理。通過改變涂層中填料比例，研究孔徑結構對甲醛氣體吸附擴散性能的影響，并利用XRD、SEM、氮氣吸附儀對涂層進行表征。結果表明，涂層的孔結構和孔徑分布對甲醛的吸附和擴散影響較大。添加硅藻土可以有效改變礦物涂層的比表面積和孔徑分布，有利于甲醛的擴散，提高吸附量。2 mm厚多孔涂層的比表面積為2.4976 m2/g，甲醛24 h吸附量為6.923 mg/m2，添加10 ％和20％硅藻土的多孔涂層比表面積分別為5.023、6.1086 m2/g，甲醛24 h吸附量分別可達7.249、7.414 mg/m2。改變填料是優化涂層結構和表面有效可行的方法，使多孔涂層有望實際應用于治理室內甲醛污染。
中圖分類號：TU56+1.6 文獻標識碼：A 文章編號：1001-702X（2020）11-0064-05
Adsorption and diffusion of formaldehyde in porous coatings
Zhao Yunpeng，Ji Zhijiang，Wang Jing，Kuang Meng
（State Key Laboratory of Green Building Materials，China Building Materials Academy，Beijing 100024，China）
Abstract：In order to solve the indoor formaldehyde pollution problem，the mineral coatings were used to adsorb formaldehyde because of its porosity. By changing the proportion of filler in the mineral coatings，the effects of the pore structure on the adsorption and diffusion performance of formaldehyde gas were studied by the double-chamber method. The coatings were characterized by XRD，SEM and nitrogen adsorption and the results show that the pore structure and pore size distribution of the porous mineral coatings have important effects on the adsorption and diffusion of formaldehyde. Adding diatomite to the porous coatings can effectively change the specific surface area and pore volume of the mineral coatings，which is conducive to the diffusion of formaldehyde and increase the amount of formaldehyde adsorption. The specific surface area of the 2 mm thick coating is 2.4976 mg/m2，and the amount of formaldehyde adsorption can reach 6.923 mg/m2 within 24 hours. The specific surface area of the porous coatings containing 10% and 20% diatomite were 5.023 m2/g and 6.1086 m2/g respectively. And the formaldehyde adsorption capacity at 24 h were 7.249 mg/m2 and 7.414 mg/m2 respectively. These results have demonstrated that changing filler is a feasible and effective method for optimizing the structure and surface of coatings，enabling coatings to become a promising candidate for the adsorption of formaldehyde in practical applications.
Key words：porous coating，formaldehyde，adsorption，diffusion，diatomite