2.1. Chemicals
All chemicals were of analytical grade and used without previous purification. Crude bentonite (Sigma-Aldrich, Oakville, Canada), sodium chloride (NaCl) (ACP chemicals, Montreal, Canada), copper acetate (Cu(CH3COO)2) (Fisher chemicals, Ottawa, Canada), silver nitrate (AgNO3) (Fisher chemicals), sodium borohydride 98% (NaBH4) (Acros organics, Ottawa, Canada), copper nitrate (Cu(NO3)2) (Anachemia VWR company, Montreal, Canada), Boltorn H20 (Perstorp, Malmo, Sweden), absolute methanol (MeOH) (Sigma-Aldrich), toluene (Sigma-Aldrich) were used. All experiments were performed in distilled water. Non-woven cellulose tissue (gauze) denoted as CT was purchased from PJC, Canada.