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In the daily life of human beings, sewage discharge and oil spill accidents occur from time to time. New types of controllable oil/water separation interface materials have received more attention. In this study, we proposed a simple and environmentally friendly method to prepare a Nickel filter with switchable wettability. The final product is prepared by high temperature calcination and soaked with stearic acid ethanol solution. The prepared filter screen has selective separation performance for oil/water mixture with switchable surface wettability between superhydrophobic and superhydrophilic. The separation efficiency is higher than 99.50%, and the flux rate is as high as 46.25 L m−2s−1 for water-removing process and 40.22 L m−2s−1 for oil-removing process. The wettability conversion of the membrane can be achieved through heating treatment and soaking treatment, and it still has good oil/water separation performance. After 20 times of cycles, the separation efficiency remains unchanged, and the flux remain above 40.06 L m−2s−1 for oil removal and 36.81 L m−2s−1 for water removal process. The results show that the prepared nickel filter screen has good practical application prospects such as water reclamation and oil spill treatment.

In order to prove the effect of bromate formation by chlorination in drinking water treatment process, by carrying out laboratory chlorination test in simulated water, Harbin drinking water and the Songhua River raw water samples, the influences of bromine ion be oxidated into bromate by chlorine were investigated. The results showed that when chlorine quantity was 5 mg/L, the conversion rate of bromide ion to bromate was less than 1.3%. On a large amount of chlorine (5 mg/L), significant bromate generation changes could not cause by the long-term existence of chlorine in the water, and the bromate concentration did not change significantly for a long period of time. In the conditions of high concentration of organic matter in water, the risk of bromate formation was low. When chlorine content reached 5 mg/L, a very small amount of bromate was detected in the raw water. New excessive risk caused by the presence of residual chlorine would not exist in the process of water supply.

Two coordination polymers, [Y(H 2 O) 4 (H 3 chhc)]·6H 2 O ( 1 ) and [Cu 5 (H 2 O) 10 (Hchhc) 2 ]·4H 2 O ( 2 ) with H 6 chhc = cyclohexane-1,2,3,4,5,6-hexacarboxylic acid) represent rare examples of metal complexes with partially protonated cyclohexane-1,2,3,4,5,6-hexacarboxylato ligands. The [Y(H 2 O) 4 ] 3+ units in 1 are interlinked by the triprotonated (H 3 chhc) 3− anions in a η 5 μ 4 bridging mode to form 2D (4 3 ) 2 (4 6 ·6 6 ·8 3 ) topological networks, which are stacked along [0 1 0] direction in ···ABAB··· fashion with the lattice H 2 O molecules sandwiched between layers. The pentameric [Cu 5 (H 2 O) 10 ] 10+ units in 2 are bridged by monoprotonated (Hchhc) 5− anions in a η 8 μ 6 fashion to generate a 3D MOF of an unprecendented (4 3 )(4 5 ·6 7 ·8 3 ) topology with the lattice H 2 O molecules in channels. The temperature-dependent magnetic susceptibility data of 2 could be modeled to a combination of a linear chain of equally-spaced Cu(II) ions ( J 1 = 1.86 cm −1 ) with an isosceles triangular Cu 3 unit ( J 2 = 5.86 cm −1 ).

Two novel porous nitrosamine traps have been synthesized in order to eliminate carcinogens from the environment. A functional mesoporous material, CuO/SBA-15, has been synthesized by using an in-situ coating method, with the addition of a guest salt to the reaction system to modify the porous materials before the particles of SBA-15 were incubated; the synthesis and modification processes were performed in a single step. The resulting mesoporous composites selectively adsorb N-nitroso-pyrrolidine (NPYR), a typical volatile nitrosamine, and are potential cigarette additives that can be used for the removal of nitrosamines from cigarette smoke, thereby protecting public health and the environment. In another reaction, silica gel is modified by being coated with magnesia and then corroded by NaOH solution.The magnesia is dispersed onto the silica by impregnating it with a magnesium acetate solution, followed by calcination. After corrosion of the calcined sample with caustic soda, only the silica particles that are completely covered by magnesia remain. This material exhibits a similar ability to SBA-15 and zeolite NaY in its selective adsorption of NPYR.

Copper oxide was incorporated into MCM-41 by a one-pot synthesis under acidic conditions to prepare a new mesoporous nitrosamines trap for protection of the environment. The resulting composites were characterized by XRD, N2 adsorption-desorption, and H2 temperature-programmed reduction techniques, and their adsorption capabilities were assessed in the gaseous adsorption of N-nitrosopyrrolidine (NPYR). The adsorption isotherms were consistent with the Freundlich equation. The copper salt was deposited onto MCM-41 during the evaporation stage and was fixed on the host in the calcination process that followed. MCM-41 was able to capture NPYR in air below 373 K but not at 453 K. Loading of copper oxide on MCM-41 greatly improved its adsorption capability at elevated temperatures. The influence of the incorporation of copper into MCM-41 samples and the adsorption behavior of these samples are discussed in detail.

New solid base with large-scale pore sizes and strong basicity was prepared by coating magnesia on amorphous silica, resulting in a composite with a basic strength ( H -) of 22.5 and large surface area exceeded 230 m 2 ·g −1 . With multi-scale structure, the modified silica exhibit a comparable ability to mesoporous materials SBA-15 and zeolite in adsorption of volatile nitrosamines like N -nitrosopyrrolidine (NPYR) or N -nitrosohexamethyleneimine (NHMI).

Copper oxide was used to modify zeolite NaY, NaZSM-5, NaA and mesoporous siliceous SBA-15, in order to strengthen their ability to remove volatile nitrosamines. Selective adsorption, temperature programmed surface reaction (TPSR) and FTIR along with TG-MS methods were employed to study the impact of copper modification on the ability of zeolite to adsorb and catalytically degrade nitrosamines. Due to the special interaction between the –N–NO group of nitrosamines and the copper in the zeolite, nitrosamines can be very easily trapped by the copper modified zeolite, and this precedes or is the first step that leads to the catalytic reaction. Moreover, modification of copper oxide enabled the zeolite to degrade nitrosamines such as N-nitrosopyrrolidine (NPYR) at lower temperatures. It is practical to use the copper modified zeolites to treat mainstream smoke or add them to tobacco, reducing further the levels of nitrosamines in cigarette smoke compared with using the zeolite alone.

Modification of zeolite with copper oxide significantly promotes the selectively adsorption of volatile nitrosamines, beneficial for the removal of nitrosamines in cigarette smoke.