Factorial experimental design of wood ceramics for ammonia nitrogen adsorption from water and analysis of the comprehensive performance

A wood ceramic matrix composites material (WCM) was synthesized using montmorillonite, MgCl2, resin, and pine wood as raw materials, and successfully employed as an adsorbent for ammonia nitrogen in water. The apparent porosity of the WCM sample was 78%, mainly composed of mesopores. The specific surface area of WCM was 13 m2/g. Research results indicate that the adsorption of ammonia nitrogen by WCM conforms well to models such as the Freundlich model, pseudo-second-order model, and intra-particle diffusion model. A fractionated experimental design investigated the effects of different variables on three properties of WCM: adsorption capacity, surface hardness, and burn-off. According to the test results, the weight of mixed raw materials, the mass ratio of wood fibre to wood powder, and the molar concentration of MgCl2 solution significantly affect the comprehensive performance of WCM. By finally optimizing the comprehensive properties of wood ceramics, the ammonia nitrogen adsorption capacity was 4.26 mg/g, the surface hardness was 551 HV, and the burnout rate was 21%.