Natural gas can be monetized through a number of different paths including the sale as fuel or as different products from chemical conversions. The development of effective strategies for natural resource monetization is important for profitable resource utilization. Environmental concerns associated with natural gas monetization include carbon dioxide emissions linked to climate change, which has caused the global community to set significant carbon dioxide emission reduction targets. This presents the oil and gas sector with the challenge to contribute to emission reduction targets, whilst maintaining profitability of operations. This work integrates the recently proposed carbon integration approach for the identification of efficient carbon dioxide reduction options in industrial parks with a natural gas allocation model that takes into account alternative monetization paths. The resulting optimization-based approach can synthesize integrated natural gas and carbon dioxide networks for industrial cities that can meet carbon dioxide emissions constraints while maximizing the profitability of natural gas monetization. The application of the method is illustrated through an example of an industrial park considering typical processes associated with natural gas monetization and carbon integration.