Substantial improvements in the control of pollutants from internal combustion engines may be obtained by pre drying a catalyst/hydrocarbon trap system and preferably incorporating {HEAD ~ a water trap} in {TAIL ~ a catalyst/hydrocarbon trap system} 
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Substantial improvements in the control of pollutants from internal combustion engines may be obtained by pre drying a catalyst / hydrocarbon trap system and preferably incorporating { HEAD ~ a water trap } in { TAIL ~ a catalyst / hydrocarbon trap system }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL