Sulfonated Phenol–Formaldehyde Resins for Highly Efficient, Selective, and Reversible Adsorption of NH<sub>3</sub>
Tan Chen, Zhang-Min Li, Ming-Shuai Sun, Hua Guan, Yan Zhou, Duan‐Jian Tao
Abstract
Currently available liquid absorbents and porous adsorbents for capturing NH 3 are often unfavorable in terms of possessing high stability and reusability. Herein, three novel sulfonated phenol–formaldehyde (SPF) resins with almost non-porosity were prepared through a facile polymerization of various phenol sulfonates with formaldehyde and applied to the adsorption of NH 3 . It is demonstrated that the SPF–Na resin displayed excellent reversibility and good stability for efficient NH 3 adsorption (12.87 mmol·g –1 ) and superior ideal adsorption solution theory selectivities for 3% NH 3 /97% N 2 (5076) and 3% NH 3 /97% H 2 (2619) at 298.2 K and 1.0 bar even in 20 adsorption–desorption cycles, whereas common PF resin only achieved a very low capacity of 1.9 mmol·g –1 . Column breakthrough results further confirmed that the SPF–Na resin showed good performance in selective adsorption of 3% NH 3 in the mixture of NH 3 /N 2 /H 2 . Nonporous SPF resins with high stability, desired capacity, and outstanding reversibility are perceived as promising solid adsorbents for effectively capturing NH 3 in the ammonia industry.