Influence of mixed molten carbonate composition on hydrogen formation by steam gasification

Abstract

Steam gasifi cation in the presence of carbonate compounds is an effective method to recover useful materials from electronic waste streams by converting plastics into gaseous products that can be used for energy production and avoiding the expensive manual disassembly process. We investigated steam gasifi cation of activated carbon in the presence of various mixtures of lithium carbonate, sodium carbonate, and potassium carbonate. The activated carbon was almost completely converted into hydrogen and carbon dioxide at 700°C under 0.1 MPa pressure in the presence of carbonate mixtures. Carbon dioxide was also derived from partial decomposition of lithium carbonate. Steam gasifi cation was accelerated in the presence of various carbonate mixtures and at increasing steam partial pressures. These experimental results show that fl uidity of carbonates, the potassium content of the carbonate, and the steam partial pressure are important factors in accelerating steam gasifi cation.

Development of sodium/lithium/fly ash sorbents for high temperature post-combustion CO 2 capture

“…The diffusion of CO 2 through the molten carbonate shell is much faster, compared to that through the solid Li/Na 2 CO 3 shell in pure Li 4 SiO 4 or pure Na 2 CO 3 [18]. Despite the fact that Li 2 CO 3 and Na 2 CO 3 have melting points higher than 700°C, the mix of the salts has melting point lower than 700°C [34].…”

Feedstock recycling of waste polymeric material

“…High yields of hydrogen were obtained with KOH and NaOH as reactants. The steam gasification of activated carbon in the presence of Li 2 CO 3 , Na 2 CO 3 , and K 2 CO 3 , respectively, resulted at 700°C in the formation of hydrogen and carbon dioxide [63]. The presence of carbonate and an increasing partial pressure of steam accelerated the hydrogen production significantly.…”

Steam gasification of printed circuit board from e-waste: Effect of coexisting nickel to hydrogen production

“…In our previous work, we could show that steam gasification using LNK-carbonate mixture (Li 2 CO 3 , Na 2 CO 3 and K 2 CO 3 ) is an effective and feasible method to recover metals contained in WEEE [34][35][36]. These metals have been used by many authors as catalysts for hydrocarbon chain reforming and hydrogenation processes.…”