SYNTHESIS IPN (INTERPENETRATING POLYMER NETWORKS) FOR CD(II) AND CU(II) ANALYSIS

• Main Author: Amalia Zikra, Rizqi
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/36206
• Institution: Institut Teknologi Bandung

Cadmium (Cd) and copper (Cu) are toxic and nondegradable heavy metals that can be accumulated in the environment. Their aquatic environment contamination was the concern in environmental problems since the accumulate of them can cause serious problems in health. The adsorption process which is largely determined by the type of adsorbent used is expected to be able to remove the heavy metal ions from the aquatic environment. Since Cd and Cu were the trace elemet metal, the metal analysis can not be conducted directly using atomic absorption spectrophotometer. Preconcentration process is needed to overcome the trace amount of these metals. In this research, the adsorbents have been synthesized with due to IPN (Interpenetrating Polymer Networks) method, based on silica xerogel and polithiourea which are used to analyze Cd2+ ions and Cu2+ ions in water sample. The synthesis of IPN was conducted in two steps. First step was preparation of silica gel as first polymer, and the second step was preparation of polythiourea as second polymer. Silica gel and polythiourea was prepared physically interprenetated each other, but not covalently bonded. The adsorbent with IPN structure was characterized using FT-IR to determine the functional groups, and also SEM for morphological analysis. The peak around 1080 cm-1 showed the presence of Si-O-Si group, peak of 1402 cm-1 shows the presence of CH2 bridge vibration wich not found in thiourea (monomer) spectrum, and the peak at 1072 cm-1 indicates the presence of S-C groups that represent the polithiourea. Some factors that influenced the adsorption such as pH, contact time and adsorption capacities were observed by batch method. Optimum adsorption conditions were obtained at pH 5 for Cd2+ and pH 6 for Cu2+, the optimum contact time was 20 minutes for adsorption of Cd (II) and 45 minutes for adsorption Cu(II). The highest adsorption capacity of IPN were 13.33 mg/g and 28.63 mg/g for Cd(II) and Cu(II) respectively. The adsorption isotherm followed the Langmuir adsorption isotherm model. In the adsorption and desorption tests, the recovery values for Cd(II) and Cu(II) were 96.86% and 99.48% respectively. While the pre-concentration of 1.3 times, the recovery value were 99.13%, for Cd(II) and 105.7% for Cu(II). Furthermore, IPN has been applied in the determination of Cd(II) and Cu(II) in river water sample. The concentrations of Cd (II) and Cu (II) in the samples were 19.03 ppb and 204.7 ppb respectively.