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Zeolitic imidazolate framework-8 (ZIF-8) has a sodalite topology. ZIF-8 is composed of zinc ion coordinated by four imidazolate rings. The pore aperture of ZIF-8 is 3.4 Å, which readily retains large gas molecules like N 2 . In this work, mixed-matrix membranes (MMMs) have been fabricated by utilizing ZIF-8 and pristine cellulose acetate (CA) for O 2 /N 2 separation. Membranes of pristine CA and MMMs of ZIF-8/CA at various ZIF-8 concentrations were prepared in tetrahydrofuran (THF). Permeation results of the fabricated membranes revealed increasing selectivity for O 2 /N 2 with increasing pressure as well as ZIF-8/CA concentration up to 5% (w/w). The selectivity of O 2 /N 2 increased 4 times for MMMs containing 5% (w/w) of ZIF-8/CA as compared with the pristine CA membrane. A thermodynamic model has also been developed to predict the permeability of gases through polymeric membranes. The results were compared with literature data as well as the pristine CA membrane produced in this work for model validation.

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Approximately 50 million ton of municipal waste is generated in Pakistan per annum and most of this waste does not reach final deposit sites. In this research, Silvia gas technology for municipal solid waste (MSW) steam gasification is studied to produce high energy density product gas. A detailed simulation model is developed with the help of Aspen Plus®. Catalyst coal bottom ash along with lime (CaO) as sorbent is employed for tar reduction and improving the hydrogen (H2) yield in the product gas. The effect of gasification operating temperature and the ratio of steam to feedstock on synthetic gas composition, hydrogen (H2) yield and heating values of synthesis gas was studied. Coal bottom ash along with CaO had a substantial effect on hydrogen (H2) yield and synthesis gas production. Rise in steam–MSW ratio increased the hydrogen (H2) from 58 to 74.9% (vol.). The maximum value of hydrogen (H2) production, i.e., 74.9% by vol. was achieved at a steam–feedstock ratio of 1.9. A maximum of 79.8% by vol. hydrogen (H2) was attained at 680 °C gasification operating temperature with 1.3 ratio of steam to feedstock and coal bottom ash 0.07% by wt. High value of 13.1 MJ/Nm3 of hydrogen-rich synthetic gas was achieved at 680 °C. The acquired results lay the foundation for the economic feasibility study and pilot plant for MSW usage for hydrogen production.