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The hydrogen in the vent gas stream of the hydrocracker (used to produce bio-jet fuel) cannot be reused since it has many impurities. The metal membrane can be a potential candidate for recovering hydrogen from this vent gas. In this work, the authors report the development of a composite palladium membrane and its application, for the first time, in the recovery of hydrogen from a simulated vent gas environment. A dense thin film (thickness ~3 µm) of Pd metal was coated on a ceramic support tube by the sputter deposition technique. The hydrogen permeance of the Pd membrane was found to be 18.75 × 10-6 mol·m-2·h-1·Pa-1, which was reduced to 3.25 × 10-6 mol·m-2·h-1·Pa-1, with an exposure of 100 h in the simulated bio-jet fuel environment. To avoid the loss of permeability, a thin layer of Pt can be coated over the Pd membrane. The present study used MATLAB software to simulate the Pt-coated Pd composite membrane performance in the bio-jet fuel production environment. Simulation studies confirmed that a membrane area of ~95 cm² (250 mm length and 12 mm OD) is sufficient for the complete recovery of hydrogen from the vent gas stream of hydrocracker at a feed velocity of 0.075 m/s. [ABSTRACT FROM AUTHOR]

90Sr (T1/2 = 28 y) is always in equilibrium with 90Y in High Level Liquid waste (HLLW) and hence 90Sr is a suitable long lasting source of 90Y, if it is purified suitably for therapeutic applications. A combination of CMPO & TBP was found to be the most suitable solvent system for alpha activity removal. CMPO has high selectivity for alpha contaminants (Pu/Am) w.r.t. 90Sr. For regeneration of spent organic, 3 M Phosphoric acid was most suitable with the ability to strip back more than 98% of gross alpha activity in single contact and thus solvent system was qualified for recycling. [ABSTRACT FROM AUTHOR]

90Y, a beta emitting radionuclide (T1/2 ~ 64 h, Emax= 2.3 MeV), the daughter product of 90Sr is used for radio therapeutic applications. Non dispersive solvent extraction in hollow fibre membrane contactor (HFMC) with CMPO solvent studies were done to achieve the desired purification of 90Sr nitrate solution with respect to gross alpha activity. This purified solution is promising feed for 90Sr–90Y generator to achieve the clinical grade product of 90Y. In HFMC recirculations, around 99.97% alpha impurities were extracted in two recirculations from the feed solution with 0.2 M CMPO while only two recirculations were required with 0.4 M CMPO. A simplified mathematical model has also been developed to model the extraction of alpha impurities through the HFMC using CMPO as a solvent. [ABSTRACT FROM AUTHOR]