## 4 Integration in TRIEX-II Facility and Experimental Investigation  
The mock-up will be installed in TRIEX-II facility, a LiPb loop for the characterization of tritium extraction technologies and technological solutions for the management of tritium balance in liquid metal for ITER and DEMO reactors.  
The facility consists of an isothermal LiPb loop with a permanent magnet pump, a saturator, a Q extraction system from LiPb and instrumentation devoted to measure the Q concentration in LiPb and to measure the LiPb mass flow rate and pressure drops for each component. The new mock-up will be installed in the test section S300 replacing the current extractor based on the Gas-Liquid Contactor technology [10].  
The mock-up will be connected with TRIEX-II LiPb loop (Figure 3) by means of two 1\" pipes equipped with two ball valves to isolate the mock-up. The inlet of LiPb will be on one side of the box, while the outlet will be positioned on the bottom of the box to allow the gravity draining. The box will be equipped with a level meter, to control the filling with LiPb, and a pressure transducer to monitor the pressure when it is filled with gas. The saturator uses the Gas-Liquid Contactor technology, where a stream of helium with a variable Q\({}_{2}\) concentration is brought into contact with a counter-current stream of LiPb. By doing this, Q\({}_{2}\) diffuses from the gas to the liquid by concentration gradient. A Mellapak 452Y structured packing supplied by Sulzer is used in the saturator to increase the interface between the two phases, thus enhancing the hydrogen isotopes solubilization in the liquid lithium-lead. The mock-up will be tested at WCLL BB relevant conditions: LiPb temperature in the range between 330-500 \({}^{\circ}\)C and LiPb mass flow rate in the range between 0.5-4 kg/s.  
Figure 3: Layout of TRIEX-II facility: S200 (in light blue) is the saturator, while S300 (in violet) is the current extractor that will be replaced by the WCLL BB mock-up. In green: LiPb storage tank; in red: residual gas analyzer (mass spectrometer); in orange: permanent magnet pump; in dark blue: hydrogen permeation sensors.  
The experimental campaign will be divided in two steps:  
1. operation in gas phase
2. operation in liquid phase  
During the first phase, the ball valves in the LiPb lines (FV07 and FV08) are intercepted and only helium with a certain percentage of hydrogen or deuterium is injected. The hydrogen that permeates inside each pipe is measured through the mass spectrometer and the PRF can be calculated as:  
\[PRF=\frac{J_{p}}{J_{c}} \tag{1}\]  
where \(J_{p}\) is the flux permeated through the pristine EUROFER pipe and \(J_{c}\) is the flux permeated through one of the coated pipes. This definition of PRF corresponds to the so-called intrinsic PRF, i.e., the PRF evaluated for the coating applied on the whole surface of a given sample.  
During the second phase, a known concentration of hydrogen or deuterium is solubilized in the LiPb by means of the TRIEX-II saturator (S200). The concentration of hydrogen in LiPb can be measured by three permeation sensors, installed upstream of the saturator, upstream and downstream of the test section [11; 12]. Also in this case, the mass spectrometer will be used to detect the amount of hydrogen that will permeate into the different pipes of the mock-up.