A Tandem Adsorption-Catalysis Strategy for the Removal of Copper Ions and Catalytic Reduction of 4-Nitrophenol.

In this work, a consecutive adsorption-catalysis approach to remove Cu2+ ions and catalytic reduction of 4-nitrophenol (4-NP) is proposed. Attapulgite (ATP) nanorods are utilized as adsorbents to enrich Cu2+ ions from contaminated water. Subsequently, the adsorbed ions were in situ reduced to construct Cu-loaded ATP catalysts. The catalytic activities of the composite ATP-Cu catalysts are evaluated by 4-NP reduction in the presence of NaBH4. The optimal ATP-Cu50 sample prepared by putting ATP into a 50 mg L-1 CuSO4 solution could complete the catalytic reaction within 4 min. Moreover, the Cu-deposited ATP nanorods can be integrated into a continuous flow catalytic system, and the 4-NP can be rapidly reduced. This method sheds lights on the fabrication of ATP-based hybrid catalysts and the removal of multiple water pollutants.

Synthesis and properties of castor oil based plasticizers.

A series of environment-friendly plasticizers has been synthesized from castor oil through a mild esterification/epoxidation reaction. The modified epoxy acetylated castor oil (EACO) can plastify poly(vinyl chloride) (PVC) efficiently, even better than the commercial plasticizers dioctyl terephthalate (DOTP) and epoxidized soybean oil (ESO), in terms of in tensile strength, migration stability, solvent extraction stability and thermal stability. Specifically, the tensile strength and elongation at break of a PVC sample plastified by epoxy acetylated castor oil (EACO) were 18.5 and 10.0% higher than that of DOTP, and 13.9 and 23.8% higher than that of ESO, respectively. Volatility, migration, solvent extraction and thermal stability tests indicated that the presence of carbon-carbon double bonds and hydroxy groups reduce the compatibility of a plasticizer with PVC while the presence of epoxy groups and ester bonds can improve the plasticizing effect of the plasticizer on PVC. In addition, alkyl groups can improve the plasticizing effect on PVC while benzene rings increase the rigidity of the PVC. The design strategy based on castor oil highlights a sustainable avenue for preparing cost-effective and high-efficiency plasticizers.