ELECTROLYZER-POWERED FLAME IONIZATION DETECTOR

We describe here a novel water electrolyzer-powered name ionization de tector (EFID), characterized by enhanced portability, reduced cost of operation and improved safety of operation and storage, A conventional FID operates with a hydrogen diffusion name, which has a central now of pure hydrogen and column effluents, surrounded by a much higher coa xial now of pure air, In contrast, the EFID is based on the combustion of a premixed (unseparated), hydrogen and oxygen, stoichiometric gas mixture, ?his premixed gas mixture is provided by a simple water elect rolyzer with low power and water consumption, without separation, comp ression, or pressure stabilization of the hydrogen and oxygen. The EFI D is very similar to mo with two minor modifications: (a) The name tip must have a narrow hole (similar to 250 mu m) to prevent flame flashb acks, (b) The entire detector structure is maintained above 100 degree s C to prevent water condensation due to the lack of diluting air, The EFID sensitivity is similar to that of the FID, and up to twice impro ved detectivity is demonstrated with the EFID, The name chemical ioniz ation yield of the EFID linearly increases with the electrolysis curre nt. The EFID response is linear over almost 6 orders of magnitude, The response is selective to carbon compounds where the response in aliph atic compounds is similar to 30% lower than with aromatic compounds, a nd no observable difference for N-, S-, P-, and Cl-containing compound s, The use of splitless solvent injections with a megabore column (0.5 3 mm i.d.) quenches the name, This name extinction is eliminated by th e use of a miniature air pump during the solvent elution time, Typical electrolyzer operating parameters are current of 1.5 A, 12 mL/day wat er consumption and 4 W electrolyzer power requirements, Thus, a relati vely small size water electrolyzer can provide the total gas consumpti on of the EFID for up to 40 days before water replenishing is required , This EFID can also be operated either as an EFID or as an FID, simpl y by replacing the gas sources.