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The biodegradation of volatile fully chlorofluonnated hydro carbons (CFCs), partly chlorofluorinated hydrocarbons (H CFCs) and vinyl chloride (VC) were investigated in compost and marl in laboratory studies. Trichlorofluoromethane (R11), dichlorodifluoromethane (R12), 1,1,2-trichlorotriflu oroethane (R113), difluoromethane (R32) and VC were bio degradable in compost under anaerobic conditions, probably by methanogenic bacteria. The anaerobic decomposition products of R11 were dichlorofluoromethane (R21 ) and chlo rofluoromethane (R31). The degradation product of R12 was chlorodifluoromethane (R22). R11 and its degradation prod ucts have the inhibiting effects of the R12 degradation under anaerobic conditions. The partly halogenated hydrocarbon R22 and VC were degraded preferentially under aerobic con ditions in marl, probably by methanotrophic bacteria. Under aerobic conditions R22 and VC have inhibited the biodegra dation of methane by methanotrophic bacteria.

PSA experiments using a two-bed laboratory-scale (100 standard liters per minute SLPM) system equipped with in-bed temperature and vapor-phase concentration probes, were performed using trichlorofluoromethane (R-11) as the feed contaminant and air as the carrier. In-bed, vapor-phase concentrations at each axial position were measured and correlated to the magnitude of the temperature swings during a cycle. The PSA experiments were then conducted using a full-scale (5,660 SLPM) system with difluorochloromethane (R-22) and 13X molecular sieve. Fourteen temperature probes were placed within a bed at different radial and axial positions. Using the temperature-concentration correlation, it was possible to construct a visual representation of the dispersion characteristics of the larger beds.