The synthesis of polyoxymethylene dimethyl ethers as an ideal diesel fuel additive is the current hot topic of modern petrochemical industry for their expedient properties in mitigating air pollutants emission during combustion. In this work

a series of spherical sulfated zirconia catalysts were prepared by a one-pot hydrothermal method assisted with surfactant cetyltrimethylammonium bromide (CTAB). The prepared sulfated zirconia catalysts were used to catalyze PODE

n

synthesis from methanol and formaldehyde solution. Various characterization (XRD

BET

SEM

TGA

NH

3

-TPD

FTIR

and Py-IR) were employed to elaborate the structure–activity relationship of the studied catalytic system. The results demonstrated that S/Zr molar ratio in precursor solution played an effective role on catalyst morphology and acidic properties

where the weak Brønsted acid sites and strong Lewis acid sites were favorable to the conversion of methanol and formation of long-chain PODE

n

respectively. The reaction parameters such as catalyst amount

molar ratio of FA/MeOH

reaction time

temperature and pressure were optimized. The speculated reaction pathway for PODE

n

synthesis was proposed based on the synergy of Brønsted and Lewis acid sites

which suggested that Brønsted and Lewis acid sites might be advantageous to the activation of polyoxymethylene hemiformals [CH

3

(OCH

2

)

n

OH

]

and methylene glycol (HOCH

2

OH)

respectively.