Liquid natural rubber (LNR) was functionalized into liquid epoxidized natural rubber (LENR) and hydroxylated LNR (LNROH)
via oxidation using a Na2
WO4
/CH3
COOH/H2
O2
catalytic system. Microstructures of LNR and functionalized LNRs
were characterized using Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies. The
effect of CH3
COOH, H2
O2
, Na2
WO4
, reaction time and temperature. reaction time and temperature on epoxy content were
investigated. LNR-OH was obtained when oxidation reaction was conducted at a longer reaction time, higher temperature
or excess amount of catalyst. Thermogravimetric analysis (TGA) reported the thermal behavior of functionalized LNRs.
Molecular weight and polydispersity index (PDI) were determined using gel permeation chromatography (GPC).
Ordered mesoporous silica with hexagonal structure, MCM-41 was synthesized under basic media using Ludox as the silica source and cetyltrimethylammonium bromide as the organic surfactant template. Organic-functionalized MPTS-MCM-41 were prepared by grafting method using 3- mercaptopropyltrimethoxysilane. The samples were characterized using FTIR, FESEM and XRD to obtain more detailed structural insights of MCM-41. The synthesized MPTS-MCM-41 were tested for adsorption of Pb(II) and Cr(III) ions in aqueous solution. Adsorption studies were analyzed using atomic absorption spectroscopy (AAS). The effect of adsorbent dose and contact time on the adsorption of Pb(II) and Cr(III) ions from aqueous solution have been investigated. MPTS-MCM-41 was found to be effective adsorbent for metal cation than parent MCM-41 with higher affinity for Pb(II) than Cr(III) from single solution. The highest percentage removal of Pb(II) was achieved at 94.59% using 0.4 g MPTS-MCM-41 at 4 hours contact time whereby the highest percentage removal of Cr(III) ions was achieved at 66.02% using 0.4 g MPTS-MCM-41 at 5 hours contact time