M A T T E R A T E X T R E M E S

S C I E N T I F I C H I G H L I G H T S

2 0 H I G H L I G H T S 2 0 2 1 I

Fig. 7: Solubility of carbonates as a

function of pressure and temperature. a)

Data from Farsang et al., Nat. Commun., 2021. b) Literature data. Full symbols

indicate upper limits for solubility. The

solid line represents a solubility line for dolomite at 400˚C

in 1 m NaCl aqueous solution. The dashed

line represents an upper solubility limit

for magnesite at 400˚C. Error bars are

only shown for (a). Note the log scale.

PRINCIPAL PUBLICATION AND AUTHORS

Deep carbon cycle constrained by carbonate solubility, S. Farsang (a), M. Louvel (b), C. Zhao (c), M. Mezouar (d), A.D. Rosa (d), R.N. Widmer (e), X. Feng (a,c), J. Liu (c), S.A.T. Redfern (f), Nat. Commun. 12, 4311 (2021); https:/doi.org/10.1038/s41467-021-24533-7 (a) Department of Earth Sciences, University of Cambridge, Cambridge (UK) (b) Institut für Mineralogie, WWU Münster, Münster (Germany) (c) Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing (China) (d) ESRF (e) Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Thun (Switzerland) (f) Asian School of the Environment, Nanyang Technological University (Singapore)

REFERENCES

[1] P.E. Van Keken et al., J. Geophys. Res. Solid Earth 116, B01401 (2011). [2] P.D. Clift, Rev. Geophys. 55, 97-125 (2017). [3] K. Li et al., Earth Planet. Sci. Lett. 516, 190-201 (2019). [4] M.L. Frezzotti et al., Nat. Geosci. 4, 703-706 (2011). [5] S. Farsang et al., Chem. Geol., 578, 120320 (2021).

Finding the active species: The conversion of methanol to aromatics over Zn-ZSM-5/alumina shaped catalysts

Industrial catalysts are more complex than model materials usually investigated in fundamental research. Here, industrial type catalysts were investigated with advanced tools to reveal how the binder material, zeolite component and metal additives function together when the active sites responsible for the catalytic performance are formed.

The zeolite-catalysed methanol-to-hydrocarbons (MTH) conversion is a promising non-petroleum alternative for

the production of high octane gasoline or base chemicals. Zn incorporation can tune the reaction towards aromatics. Most fundamental research is done using pure, powdered zeolites as catalysts. However, structuring and shaping using binder materials is necessary for the industrial utilisation of zeolites. This adds a little-explored complexity level.

This work studied sphere-like catalysts prepared by spray- drying a slurry containing ZSM-5 and alumina (Al2O3). These spheres were later impregnated or ion-exchanged to incorporate Zn. The catalytic performance of these materials for the conversion of methanol to aromatics was investigated and extensive characterisation was carried out, including X-ray absorption spectroscopy (XAS) at beamline BM23.