Processes and systems are provided for removing contaminants from a vapor stream containing hydrocarbon and hydrogen, and can include: providing a feed stream to a first pressurized vapor liquid separator that produces a liquid stream and a vapor stream containing hydrocarbon and hydrogen, passing the vapor stream to an inlet of a particulate trap containing a plurality of treatment zones that remove contaminants from the vapor stream to produce a particulate trap effluent, and passing the particulate trap effluent directly to a catalytic hydrogenation zone. The processes and systems can also include: passing the liquid stream from the first pressurized vapor liquid separator to a second vapor liquid separator that produces an overhead vapor stream and a liquid bottoms stream, condensing the overhead vapor stream from the second vapor liquid separator to form a liquid overhead stream, routing the liquid overhead stream to the inlet of the particulate trap.