Electronic Theses and Dissertation

Studi proses pengolahan limbah air asam tambang (AAT) yang dihasilkan di area pertambangan menjadi perhatian khusus untuk penanganan logam berat seperti mangan (Mn). Penelitian ini melakukan pengolahan penghilangan logam berat mangan dari air asam tambang sintetis dengan metode batch. Salah satu pengolahan yang tepat digunakan adalah adsorpsi menggunakan adsorben tanah diatome nanopartikel. Tujuan penelitian ini yaitu mempelajari kemampuan tanah diatome nanopartikel sebagai adsorben pengurangan kadar logam berat mangan. Penelitian diawali dengan melakukan sintesis tanah diatome menggunakan metode sol-gel dan untuk mendapatkan adsorben dalam ukuran nanopartikel dilakukan proses aktivasi fisika dengan cara adsorben di kalsinasi pada suhu 600 dan 800oC kemudian dilakukan karakterisasi menggunakan SEM, BET, XRD dan FTIR. Pengamatan proses adsorpsi dilakukan dengan metode batch, dimana mengamati pengaruh hasil aktivasi adsorben diatome nanopartikel terhadap peningkatan kemampuan kinerja adsorben dalam berbagai variasi konsentrasi (25 - 125 ppm) dan melihat pengaruh waktu kontak (30 - 150 menit) terhadap penyerapan ion logam mangan yang dianalisis menggunakan AAS. Selanjutnya menentukan kinetika adsorpsi dan mempelajari isotherm Langmuir, Freundlich, Temkin dari adsorpsi mangan menggunakan tanah diatome nanopartikel serta melakukan optimasi proses menggunakan metode rancangan yaitu Respon Surface Method (RSM) dengan Central Composite Design (CCD). Hasil penyerapan logam mangan dalam limbah air asam tambang memberikan pengaruh terhadap waktu dan kapasitas adsorpsi, dimana semakin tinggi suhu aktivasi maka daya penyerapan logam semakin cepat. Kinetika adsorpsi logam mangan dalam air asam tambang sintetis diperoleh koefisien regresi tertinggi yaitu 0,8761 pada perlakukan suhu kalsinasi 600 oC sehingga diperoleh persamaan laju reaksi pada orde reaksi satu, untuk suhu 800 oC koefisien regresi yaitu 0,7665 dengan persamaan laju pada orde reaksi satu. Penentuan isotherm adsorpsi pada adsorben diatome dengan suhu kalsinasi 600 oC dan 800 oC diperoleh nilai koefisien regresi tertinggi pada persamaan isotherm TemKim dengan nilai koefisien regresi masing-masing adalah 0,9326 dan 0,966. Optimasi proses menggunakan metode rancangan Respon Surface Method (RSM) dengan Central Composite Design (CCD) berdasarkan hasil optimasi diperoleh nilai optimum untuk daya adsorpsi suhu kalsinasi 600 oC yaitu 12,570 dengan nilai desirability 0,817, daya adsorpsi suhu 800 oC yaitu 13,313 dengan nilai desirability 0,808.

Kata kunci: Tanah diatome, sintesis sol-gel, adsorpsi, batch, air asam tambang, Respon Surface Method

The process study of processing acid mine drainage (AMD) produced in mining areas is a particular concern for handling heavy metals such as manganese (Mn). This research will carry out the removal of heavy metals manganese from synthetic acid mine drainage using a batch method. One of the suitable treatments is adsorption using diatomaceous earth nanoparticle adsorbents. The aim of this research is to study the ability of nanoparticle diatomaceous earth as an adsorbent for reducing levels of manganese heavy metals. The research was initiated by synthesizing diatomaceous earth using the sol-gel method and to obtain adsorbents in nanoparticles size, a physical activation process was carried out by calcined the adsorbent at 600oC and 800oC and then characterizing using SEM, BET, XRD, and FTIR. Observation of the adsorption process was carried out using a batch method, which observed the activation effect of diatomite nanoparticle adsorbents on the increase in performance of adsorbent in various concentrations (25 - 125 ppm) and saw the effect of contact time (30 - 150 minutes) on the absorption of manganese metal ions analyzed using AAS. Furthermore, determining the adsorption kinetics and studying the Langmuir, Freundlich, Temkin isotherms of manganese (Mn) adsorption using nanoparticle diatomaceous earth and perform process optimization using the design method, namely the Response Surface Method (RSM) with Central Composite Design (CCD). The results of the absorption of manganese (Mn) in acid mine waste water have an effect on the adsorption time and capacity, where the higher the activation temperature, the faster the absorption of metals. The kinetics of the adsorption of manganese and sulphide in synthetic acid mine water obtained the highest regression coefficient of 0.8761 at a calcination temperature of 600 oC so that the reaction rate equation was of the first order of reaction, for a temperature of 800 oC the regression coefficient was 0.7665 with a rate equation of the order of reaction one. Determination of adsorption isotherm on diatomaceous adsorbent with calcination temperature of 600 oC and 800 oC obtained the highest regression coefficient value in the TemKim isotherm equation with a regression coefficient value of 0.9326 and 0.966. Optimization of the process using the Response Surface Method (RSM) with Central Composite Design (CCD) based on the optimization results obtained the optimum value for the adsorption power of 600 oC temperature is 12.570 with a desirability value of 0.817, the adsorption power of 800 oC is 13.313 with a desirability value of 0.808. Keyword: Diatomaceous earth, sol-gel synthesis, adsorption, batch method, acid mine drainage, Respon Surface Method