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The remediation of wastewater containing Pb2+has attracted much attention due to the harm of Pb2+to the environment and human health. A promising adsorbent, functionalized montmorillonite modified with a ligand diethylenetriamine (DETA) was prepared under mild reaction conditions. The modified montmorillonite (DETA-MMT) and nature montmorillonite (Na-MMT) were then characterized with the help of XRD, FTIR, TG/DTG, and BET. It was revealed that the modifier DETA was successfully inserted into interlayers of montmorillonite, as demonstrated by the characterizations. Batch adsorption experiments of Pb2+onto Na-MMT and DETA-MMT in solutions were studied as a function of various parameters, such as pH, contact time, initial concentration, and temperature. The maximum adsorption capacity of DETA-MMT was 61.1 mg g–1, which had more than doubled compared with that of Na-MMT. The adsorption thermodynamics of Pb2+by DETA-MMT was studied, and it showed a endothermic process. The adsorption kinetics of two samples both fit well with the pseudo-second-order model. The adsorption isotherms of Na-MMT and DETA-MMT can be well described by the Langmuir isotherm and Freundlich isotherm, respectively. Furthermore, the adsorbed Pb2+onto DETA-MMT can hardly be dissolved under weak acidic condition (pH >4) according to the desorption experiments of simulated acid rain and Tessier’s sequential extraction procedure.

For the first time we have successfully constructed semi conductive copper–biphenylamines framework hybrid photocatalysts to degrade organic pollutants. Cu complexes sensitized photocatalysts of g-C3N4, i.e.CN-Cu(BN), CN-Cu(PD) and CN-Cu(BA), have been successfully tested for photocatalytic degradation of organic pollutants under visible light illumination, and a significant enhancement in catalytic activity was observed for CN-Cu(BA) in comparison to pristine g-C3N4. The modified material creates a charge separation with the electrons populating the higher CB and the holes the lower VB, thus enhancing the redox reaction power of the charge carriers. CN-Cu (BA) can easily degrade 99% of RhB in 1.5 hours and 60% of phenol in 2 hours. While the degradation efficiency of CN-Cu(BN), CN-Cu(PD) and g-C3N4is lower than that of CN-Cu(BA). The kobsfor CN-Cu(BN) is 0.01985 min−1, 5.2 times higher than that of g-C3N4, and that of CN-Cu(BA) is 0.0292 min−1which is 7.55 times greater than that of pristine g-C3N4. These degradation outcomes are favourable for developing a modified catalyst in bulk amount and its application. The strong holes can directly degrade RhB and phenol. Promoting the injection of electrons from g-C3N4into the copper unit as well as strengthening the electronic interactions between the two units enhanced its activity.