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Hydrate formation apparatus reported so far was mainly concentrated in stirred-tank batch environments. It was difficult to produce the high gas storage hydrate efficiently. Some nonstirred technology has been attracting more attention by researchers. This work proposed a new apparatus for hydrate formation by spraying water into a gaseous phase with a fine nozzle. It can get sufficient contact surface area for gas-liquid reaction. Methane hydrate formation experiments have been conducted using pure water and sodium dodecyl sulfate (SDS) aqueous solution for comparison at 277.15 K. The experiments were conducted at 7.0 and 6.0 MPa, respectively. Kinetics of methane hydrate formation have been investigated by methane consumption per mole of water and reaction rate. The mechanism of hydrate formation and kinetics property by spraying atomization were studied with the theory of crystal chemistry.

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A series of copolyamic acid (PAA) were synthesized from various ratios of two diamines p-phenylene diamine and 4,4′-oxydianiline (ODA) via copolymerization with pyromellitic dianhydride (PMDA) in polar solvent dimethylacetamide. A mixture of acetic anhydride and triethylamine was used as the cyclizing agent and added to the PAA in order to chemically convert it into partly imidized PAA, which then was spun into fibers by dry-jet wet-spinning. Finally, polyimide (PI) fibers were prepared after the as-spun fibers had been heat-treated. The results indicated that the intrinsic viscosity of partly imidized PAA was higher than that of pure PAA. Moreover, when the partly imidized PAA was spun into a suitable composition coagulation bath, the as-spun fibers gained a circular and dense internal morphology. The tensile strength and initial modulus of the heat-treated PI fibers were better than those of the homo-PI PMDA-ODA fibers, respectively, and the thermal stability of the PI fibers was also enhanced.