Research continued on hot gas desulfurization. Antek Instruments reported success in the use of a quartz capillary tube having a diameter of about 0.005 inches and a length of 6 inches to reduce the pressure of a 600{degrees}C gas stream from 15 atm to 1 atm. This capillary tube will be incorporated into the Antek R-6000 elemental sulfur analyzer; an order was placed for the modified instrument during the latter stages of the quarter. SO{sub 2} and H{sub 2}S analysis will be accomplished by modifying an existing Shimadzu GC-14A gas chromatograph. Repairs to both the electrobalance and the furnace temperature controller were accomplished and a manifold system capable of feeding N{sub 2}, O{sub 2}, H{sub 2}, and H{sub 2}O was constructed. A number of calibration and scoping tests were completed, and atmospheric pressure testing of the regeneration of FeS with O{sub 2}/N{sub 2}, H{sub 2}O/N{sub 2} and O{sub 2}/H{sub 2}O/N{sub 2} atmosphere is scheduled to get underway early in the next quarter. Key components of the reactor system, including the data acquisition computer, furnace and temperature controller, gas feed manifold, high pressure syringe pump, and back pressure regulators, were last used in a fixed-bed reactor study. Primary effort during the quarter was devoted to correcting problems with the data acquisition system and reassembling the components for the high pressure electrobalance. Scoping and calibration testing of this unit is scheduled to get underway early in the following quarter.