Sintesis Komposit Kitosan/Zeolit/Magnetit sebagai Adsorben untuk Tembaga(II)

RAHMATUN NISA'I, Dr. Suyanta, M.Si; Dr. Sutarno, M.Si/Prof. Dra. Wega Trisunaryanti, MS., Ph.D.Eng; Dr. Nurul Hidayat Aprilita, M.Si

2017 | Skripsi | S1 KIMIA

Sintesis komposit kitosan/zeolit/magnetit sebagai adsorben untuk mendekontaminasi logam Cu(II) di dalam perairan telah dilakukan. Sintesis komposit diawali dengan modifikasi zeolit alam teraktivasi dengan magnetit kemudian dimodifikasi dengan kitosan tertaut silang glutaraldehid menggunakan metode kopresipitasi. Komposit di karakterisasi dengan FTIR, XRD, VSM dan TEM. Kinetika adsorpsi komposit kitosan/zeolit/magnetit terhadap logam Cu(II) dikaji dalam 4 model kinetika yaitu orde satu Santosa dan Muzakky, orde satu semu Lagergren, orde dua Langmuir-Hinshelwood dan orde dua semu Ho dan Mckay. Isoterm adsorpsi komposit kitosan/zeolit/magnetit dipelajari menggunakan persamaan isoterm adsorpsi Langmuir dan Freundlich. Sebagai material yang mengandung magnetit, dilakukan uji recovery material komposit kitosan/zeolit/magnetit setelah adsorpsi menggunakan medan magnet eksternal . Uji FTIR menunjukkan Gugus-gugus fungsional pada material komposit-kitosan/zeolit/magnetit terdiri dari gabungan kitosan, zeolit dan magnetit yaitu Si-O, R-NH2, -OH dan Fe-O. Uji kristalinitas dengan XRD menunjukkan penurunan kristalinitas magnetit dalam komposit kitosan/zeolit/magnetit. Kurva histeresis VSM yang semakin pendek antara magnetit murni, zeolit/magnetit dan kitosan/zeolit/magnetit menunjukkan penurunan sifat kemagnetan. Uji morfologi dengan TEM menunjukkan kandungan magnetit berkurang ketika komposit zeolit/magnetit dikompositkan dengan kitosan. Kinetika adsorpsi Cu(II) oleh komposit kitosan/zeolit/magnetit mengikuti model kinetika orde dua semu Ho dan Mckay dengan nilai K sebesar 0,0376 g/mg.menit dan mengikuti Isoterm adsorpsi Langmuir dengan harga Q0 sebesar 4,2808 mg/g dan RL sebesar 0,023 � 0,051. Uji recovery menunjukkan komposit kitosan/zeolit/magnetit dapat dipisahkan dengan mudah dan cepat menggunakan medan magnet eksternal.

Synthesis of Chitosan/zeolite/magnetite composite as adsorbent for Cu(II) metal decontamination has been conducted. Synthesis was started by modification of activated natural zeolite with pure magnetite using coprecipitation, then modified with chitosan cross-linked by glutaraldehyde. Composite was caracterized using FTIR, XRD, VSM and TEM. The effects of pH value of Cu(II), contact time, and Cu(II) concentration on adsorption of composite toward Cu(II) were investigated. The kinetics data of adsorption process were analyzed by four models, which are first order adsorption Santosa and Muzakky, Lagergren pseudo first order adsorption, Langmuir and Hinshelwood adsorption and pseudo second order adsorption Ho dan Mckay. Adsorption isotherms were determined using Langmuir and Freundlich equation. As a magnetic material, recovery capability of chitosan/zeolite/magnetite composite was examine using external magnetic. FTIR characterization showed that the fungtional groups of Chitosan/zeolite/magnetite composite, consist of chitosan, zeolite and magnetite fungsional groups combination, Si-O, R-NH2, -OH and Fe-O respectively. XRD shown cristalinity of magnetite in chitosan/zeolite/magnetite composite decreased. Hysteresis curve of VSM showed the reduction of magnetic properties significantly from pure magnetic to zeolite/magnetite composite and chitosan/zeolite/magnetite composite. TEM image showed that the addition of chitosan to zeolite/magnetite reduced the ammount of magnetite in chitosan/zeolite/magnetite composite. Adsorption kinetic of chitosan/zeolite/magnetite composite toward Cu(II) followed Ho dan Mckay pseudo second order with K 0.0376 g/mg.minute while adsorption Isoterm follows Langmuir equation with Q0 4.2808 mg/g and RL 0.023 � 0,051 respectively. Recovery examination shown that chitosan/zeolite/magnetite composite was quick and easy to separate from solution after adsorption using external magnetic.

Kata Kunci : kitosan, zeolit, magnetit, kopresipitasi, Adsorpsi Cu(II)/Chitosan, zeolite, magnetite, copresipitation, Cu(II) Adsorption