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Five kinds of polyimides were synthesized using five dianhydrides (including 2,2-bis[4-(3,4-dicarboxyphenoxy)-phenyl] propane dianhydride (BPADA), 3,3′,4,4′-diphenylsulfone-tetracarboxylic dianhydride (DSDA), 4,4′-(hexafluoroisopropylidene)-diphthalic anhydride (6FDA), 1,4-bis(3,4-dicarboxyphenoxy) benzene dianhydride (HQDPA), and 4,4′-oxydiphthlic dianhydride (ODPA)) and 2,2-bis[4-(4-aminophenoxy)phenyl] hexafluoropropane (BDAF) via the two-step method that included polyaddition to form the polyamic acid and subsequent chemical imidization at ambient temperature. The structures of polyimides were characterized by FTIR and NMR. The thermal properties were characterized by DSC and TGA. All five kinds of polyimides showed good thermal properties and solubility in organic solvents such as DMF, DMAc, NMP and THF at room temperature. The pervaporation (PV) experiments of polyimides for toluene/n-heptane mixture were carried out, and all the polyimides showed selective permeation towards toluene. The fluxes of 6FDA-BDAF, DSDA-BDAF, HQDPA-BDAF and ODPA-BDAF at 80°C were 1.08, 0.96, 1.77 and 0.10 kg·μm/(m²·h), and the separation factors were 5.44, 1.64, 1.28 and 11.44, respectively. The increasing feed temperature resulted in higher flux and lower separation factor of the 6FDA-BDAF membrane.

Nanosized Cu–Mn composite oxide catalysts were prepared from potassium permanganate, copper nitrate, n-butanol, and cetyltrimethylammonium bromide as a manganese source, copper source, reducing agent, and surfactant, respectively. The Cu${}_{0.2}$–Mn sample possessed a small particle size (10–40nm) and a relatively high specific surface area ($46.24{\mathrm{\text{m}}}^2\cdot {\mathrm{\text{g}}}^{-1}$); its main components were Cu${}_{1.5}$Mn${}_{1.5}$O₄ and Mn₃O₄. As a consequence, the Cu${}_{0.2}$–Mn catalyst exhibited good catalytic activity in the oxidation of toluene. At a toluene concentration of 1000ppm and a space velocity of $60,000\mathrm{\text{mL}}\cdot {\mathrm{\text{g}}}^{-1}\cdot {\mathrm{\text{h}}}^{-1}$, the $T_{50}$ and $T_{90}$ of the Cu${}_{0.2}$–Mn catalyst toward toluene were 239${}^{\circ }$C and 250${}^{\circ }$C, respectively. Furthermore, even after 30h of operation at 275${}^{\circ }$C, the conversion of toluene was 99% (at the space velocity of $60,000\mathrm{\text{mL}}\cdot {\mathrm{\text{g}}}^{-1}\cdot {\mathrm{\text{h}}}^{-1}$).

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…