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Synthesis of amino functionalized organosilane (AFOS) via UV-irradiation method has been conducted. In this research, the precursors for synthesizing AFOS are 3-glycydiloxypropyl trimethoxysilane (GPTMS) and ethylene diamine. Synthesis of amino functionalized organosilane was performed for 16 h monitored by Infra-red spectroscopy technique. The morphological structure of AFOS was observed by scanning electron microscopy. The adsorption process was conducted in the batch method using Remazol Brilliant Blue R (RBBR) as anionic dye model. In this study, the pH, contact time and dyes concentration were varied to determine the optimum pH, kinetic and isotherm adsorption. Based on the calculation, the kinetic rate of the RBBR adsorbed onto AFOS was determined by k2 (pseudo second-order). Moreover, the isotherm study showed that the Langmuir model fitted for the adsorption of RBBR onto AFOS with Qm by 21.3 mg g-1.

Biosurfactant with efficient emulsification properties could be produced by Pseudomonas flourescens using cassava flour wastewater (manipueira) as media. The ability of P. flourescens to produce biosurfactant could suggest potential use in industrial and environmental applications. Media containing a mixture of natural manipueira and nutrient broth with 48 h fermentation was the optimum condition for the biosurfactant production. Based on UV-Vis and FT-IR spectra, the biosurfactant was indicated as rhamnolipids containing hydroxyl, ester, carboxylic and aliphatic carbon chain functional groups. Biosurfactant exhibited critical micelle concentration (CMC) value of 715 mg/L and reduced the surface tension of the water from 80 mN/m to 59 mN/m. The biosurfactant was able to decrease the interfacial tension about 51-70% when benzyl chloride, palm oil and kerosene were used as water-immiscible compounds. The biosurfactant was able to form stable emulsion until 30 days when paraffin, soybean oil, lubricant oil and kerosene were used as water-immiscible compounds.

The aim research is application of poly-5-allyl-calix[4]arene tetra carboxylic acid as adsorbent of heavy metal cations. Adsorption was carried out towards Pb(II), Cd(II) and Cr(III) ions in batch system. Several variables including pH, contact time and initial concentration of metal ions were determined. The optimum adsorption conditions were achieved at pH 6.0 for Cd(II) and Cr(III), while at pH 5.5 for Pb(II) ions. In addition, the optimum contact time of Pb (II), Cd(II) and Cr(III) ion adsorption were 180 min. The adsorption kinetics of Pb(II), Cd(II) and Cr(III) ions using the calixarene polymer adsorbent followed a pseudo 2nd order kinetics model, with adsorption rate constants of 2x10-2; 5x10-3, and 3.1x10-2 g mole-1 min-1, respectively. Furthermore, the adsorption isotherm of Pb(II) and Cd(II) ions tends to follow the Freundlich isotherm, whereas the adsorption of Cr (III) tends to follow the Langmuir isotherm. The adsorption capacity of Pb(II), Cd(II) and Cr(III) metal ions were 104.04, 61.78 and 228.69 μmole/g, with adsorption energy of 24.87; 21.62 and 31.07 KJ/mole, respectively.

The synthesis of poly-5,7-diallyl-25,26,27,28-tetrahydroxycalix[4]arene were performed in experimental series as follows: (1) Cyclotetramerization of p-t-butylphenol with NaOH and paraformaldehyde to p-butylcalix[4]arene, (2) Debutylation of p-butylcalix[4]arene using AlCl3 and phenol to tetrahydroxycalix[4]arene, (3) Allylation reaction using allylbromide to diallyloxy-dihydroxycalix[4]arene, (4) Claisen rearrangement reaction, (5) Cationic polymerization to diallylcalix[4]arenes. All of the synthesized products were analyzed by means of IR spectrometer and 1H-NMR spectrometer. The result of 25,27-diallyloxy-26,28-dihydroxycalix[4]arene synthesis was white crystals having m.p. 205-207 °C in 80.95% yield. The synthesis of 5,7-diallyl-25,26,27,28-tetrahydroxy-calix[4]arene gave light yellow crystals having m.p. 214-216 °C in 78.67% yield. The polymerization gave poly(5,7-diallyl-25,26,27,28-tetra-hydroxycalix[4]arene) having m.p. 338-340 °C, in 60% yield. Its estimated has a relative molecular weight of 18,738 g/mol with the number of unit repetition about 37 monomer units. Keywords: Diallylation, polymerization, Poly-5,7-diallyl-25,26,27,28-tetrahydroxycalix[4]arene