Inexpensive metal oxides nanoparticles doped Na2CO3 fibers for highly selective capturing trace HCl from HCl/CO2 mixture gas at low temperature

Abstract

A novel inexpensive metal oxides doped sorbents had been investigated for selective capture of hydrogen chloride (HCl) from HCl/CO2 (1:25 v/v) mixture gas at 150 °C. In this work, metals oxides (Fe, Mn, Ce and Cu) grains supported on the Na2CO3 fibers were firstly prepared via ultrasonic atomization loading method, respectively. The results of HCl removal experiments showed that Cu dopant with optimal content synergistically facilitated HCl capture performance, continuously removing HCl from initial content of 1% to less than 1 ppm as long as 6.5 h. And the HCl capacity reached 3.15 mmol/g, corresponding to the conversion of active component Na2CO3 was up to 0.89. Meanwhile, the Cu doped sorbent exhibited a strongly selective adsorption of HCl under extreme lower volume ratio HCl/CO2 of 1:25. The enhancement of Na2CO3 reactive activity depended on the highly dispersed copper oxides nanoparticles on the surface of Na2CO3 fibers. CuO species in copper oxides reacted with HCl to form CuCl2, while the presence of amorphous phase connecting CuO nanoparticles and Na2CO3 strongly promoted the mass transfer in product layers. The intensification of these two aspects made copper doped adsorbent exhibited significant HCl removal performance. Moreover, during regeneration test, the sorbents could maintain fairly stable cyclic performance within three cycles.