Accelerated synthesis of zeolites via radicalized seeds
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By means of milling and heating, the zeolite crystals can be radicalized forming surface non-bridging oxygen hole center (NBOHC, ≡Si–O·). The corresponding g values of 2.0043 and 2.0048 unambiguously confirm the existence of the ≡Si–O· radicals in the milled and heated crystals via electron paramagnetic resonance. The active ≡Si–O· radicals can react with water to form hydroxyl free radicals to accelerate the crystallization of zeolite along with seeds. Radicalized crystals are used as seeds that show obvious accelerating effect in the crystallization of Na-A and nanosized silicalite-1 than the non-radicalized seeds. At the same crystallization time, solid products with much better crystallinity and more yields could be obtained using radicalized seeds compared with non-radicalized seeds. A new seeding-synthesis-related strategy is developed to accelerate the crystallization of zeolites.
We appreciate Prof. Jihong Yu and Wenfu Yan in Jilin University for helpful discussions. This work was supported by the National Natural Science Foundation of China (Grant No. 21701117), the Natural Science Foundation of Liaoning Province (20180550062), and the Special Fund of Liaoning Provincial Universities’ Fundamental Scientific Research Projects (LZD201702, LQN201706).
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Conflict of interest
The authors declare that they have no conflict of interest.
- 3.Breck DW (1974) Zeolite molecular sieves. Wiley, New YorkGoogle Scholar
- 4.Xu RR, Pang WQ, Yu JH, Huo QS, Chen JS (2009) Chemistry of zeolites and related porous materials: synthesis and structure. Wiley, HobokenGoogle Scholar
- 7.Chu P, Dwyer FG, Vartuli JC (1988) Crystallization method employing microwave radiation. US Patent 4 778 666Google Scholar