Optimized Preparation of Nanosized Hollow SSZ-13 Molecular Sieves with Ultrasonic Assistance.

Because of its unique eight-membered ring pore structure and the arrangement of cations in its structure, the SSZ-13 molecular sieve has a higher affinity for CO2 than other gases, meaning it has attracted more attention than other porous materials for CO2 adsorption. However, the expensive template and long preparation time limits the industrial production of SSZ-13. In this work, a hollow structure was successfully introduced into the nanosized SSZ-13 molecular sieve with ultrasonic treatment. The effects of the amount of seed added and the ultrasonic time on the structure were investigated. When the amount of seed added was 0.5 wt.% and the ultrasonic time was 60 min, the sample showed a hollow cubic crystal with a diameter of about 50 nm. The specific surface area reached 791.50 m2/g, and the mesoporous ratio was 66.3%. The samples were tested for CO2 adsorption performance at 298 K. It was found that the hollow sample prepared in this work has higher CO2 adsorption capacity compared with the SSZ-13 zeolite prepared with conventional methods. When the adsorption pressure was 0.27 bar, the adsorption amount reached 2.53 mmol/g. The hollow SSZ-13 molecular sieve reached a CO2 adsorption capacity of 4.24 mmol/g at 1 bar.

Tuning aluminum spatial distribution in ZSM-5 membranes: a new strategy to fabricate high performance and stable zeolite membranes for dehydration of acetic acid.

A novel ZSM-5 membrane with a low Si/Al ratio and homogeneous aluminum spatial distribution was achieved from an organic template-free inorganic gel in the presence of both OH(-) and F(-) ions and the obtained ZSM-5 membrane exhibited excellent selectivity and high flux and stability for dehydration of acetic acid in a wide AcOH content range.

A highly permeable and selective amino-functionalized MOF CAU-1 membrane for CO2-N2 separation.

A thin tubular CAU-1 membrane of 2-3 µm exhibiting a high CO2 permeance of up to 1.34 × 10(-6) mol m(-2) s(-1) Pa(-1) and a CO2-N2 selectivity of 17.4-22.8 for CO2-N2 mixtures was achieved, demonstrating for the first time that amino-functionalized MOF membranes can provide high CO2-N2 selectivity and possess the potential for CO2 capture from flue gas.

Deposition of chemically modified α-Al2O3 particles for high performance ZIF-8 membrane on a macroporous tube.

Through deposition of APTES-functionalized Al2O3 particles onto a coarse macroporous support, a new strategy to reduce the pore size and simutaneously promote a high density of heterogeneous nucleation sites was developed, and a continuous and thin ZIF-8 membrane exhibiting remarkably high H2 permeance of 5.73 × 10(-5) mol m(-2) s(-1) Pa(-1) and H2/N2 ideal selectivity of 15.4 was achieved.

Pd-silicalite-1 composite membrane for direct hydroxylation of benzene.

Pd membranes of excellent stability and flux were prepared with multi-legged anchors by electroless plating of Pd on a porous support modified by a zeolite barrier layer containing Pd seeds; these membranes provide stable phenol production by direct hydroxylation of benzene.