Requirements of Methane Functionalization Chemistry Influenced by Plant Design

Requirements of Methane Functionalization Chemistry Influenced by Plant Design 

In developing this next-generation direct methane to methanol process, several key considerations are important. As a general consideration it should be expected that any new process not only substantially reduces the capital costs for the process (ideally by 50%) but also meets (and desirably exceeds) the overall yield and atom-efficiency of the existing process. Significantly, giving the eco- 

Bubble column Inexpensive . Good heat transfei 

As can be seen, two key advantages of utilizing this process design are A) air, instead of pure oxygen, can be utilized for the reoxidation and B) inexpensive gas-liquid bubble column reactors can be employed. Since these reactors can be designed to operate at comparable pressures and temperatures, there is no disadvantage to separating the alkane reaction from reactions with air. 

For the catalyst to be useful it must meet minimum cost requirements. Most efficient reactor systems operate at volumetric productivities or Space Time Yields (STY) of -10 mol/cc s (this is the amount of product that must be generated per unit reactor size per unit time). The reactor STY is related to catalyst activity and concentration by the relationship STY=TOFx[Cat], where TOF is the catalyst turnover frequency and [Cat] is the catalyst concentration. Typically for nobel metal catalysts, given the enormous daily productivity of world-scale plants, the desired catalyst concentration to be economical is - 1 mM. This leads to a required catalyst rate (TOF) of -1 s in order to be cost effective (Table 7.1). To put these challenges in perspective, validation that these guidelines 

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