Facilitated transport of silver(I) cation across a bulk liquid membrane by two synthesized ligands, bis-β-enamino ester (BBEE) and bis(benzoic acid) trioxaheptane (BBAT), as carriers dissolved in dichloromethane has been investigated. BBEE was used as a specific ion carrier for the transport of silver(I) ion. The influence of experimental parameters affecting the transport efficiency of silver(I) ion have been studied. In the presence of thiosulfate as a suitable metal ion acceptor in the receiving phase and picrate ion as ion pairing agent in the source phase, the amount of silver(I) ion transported across the liquid membrane after 120 min was found to be 97%. Tolerance to the presence of different ions was investigated and it was found that silver(I) cation transport was not affected even in the presence of 10-fold concentration of these metal cations in solution. This system was applied for the recovery of silver(I) cation from silver plating and photographic waste solution.

N,N',N'',N'''-Tetrametil tetra(2,3-piridil)porfirazinato metil sulfato de cobre(II) ([Cu(2,3-tmtppa)](MeSO4)4) catalisou com sucesso a conversão direta de nitrilas a amidas N-substituídas. A síntese seletiva do tipo one pot de amidas N-substituídas a partir de nitrilas e aminas primárias foi realizada em refluxo de água. O catalisador foi recuperado e reusado no mínimo 4 vezes, mantendo a sua eficiência.

N,N',N'',N'''-Tetramethyl tetra-2,3-pyridinoporphyrazinato copper(II) methyl sulfate ([Cu(2,3-tmtppa)](MeSO4)4) efficiently catalyzed the direct conversion of nitriles to N-substituted amides. The one pot selective synthesis of the N-substituted amides from nitriles and primary amines was performed in refluxing H2O. The catalyst was recovered and reused at least four times, maintaining its efficiency.

In this work, we introduce a highly selective and sensitive silver(I) PVC-membrane sensor. Dilaktam Crown ether (DLCE) was used as a membrane-active component to prepare a highly sensitive Ag(I)-selective polymeric membrane electrode. This sensor illustrated very good selectivity and sensitivity towards silver ions over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The sensor exhibited a Nernstian behavior (with a slope of 59.8 ± 0.2 mV per decade) for a concentration range (1.0 x 10-5-1.0 x 10¹ M) with a detection limit of 6.8xl0-6 M. It displayed a response time in the whole concentration range (~20 s) and its usage exceeded a 75 days period in the pH range of 5.1-7.2. The proposed electrode application was found to be successful as an indicator electrode in the titration with NaCl.