Room-temperature catalyst-free methane chlorination

The chlorination of methane presents a route for the upgrading of natural gas to value-added products. However, due to the low reactivity of methane, existing chlorination processes require the use of elevated temperatures and catalysts. Here, we report a simple process for the chlorination of methane at near-ambient temperatures using minimal reagents and no catalysts or external sources of energy. The reaction is carried out in an aqueous medium with trichloroisocyanuric acid as a chlorinating agent. The dissolution of trichloroisocyanuric acid in water leads to the sustained and buffered release of hypochlorous acid, which triggers the chlorination of methane by a free-radical mechanism. The process is also general to other alkanes, as shown by a similar chlorination of ethane. Further developments are required for this process to be deployed as a practical method of chloromethane production.

Automated summary

The research introduces a simple process for chlorination of methane at near-ambient temperatures using minimal reagents and without the need for catalysts or external energy sources. The reaction is carried out in an aqueous medium with trichloroisocyanuric acid releasing hypochlorous acid to trigger the chlorination process. The method is shown to be applicable to other alkanes but further developments are needed for practical chloromethane production.