No abstract

Synthesis of zeolite from Ende-Nusa Tenggara Timur (NTT) natural zeolite was conducted using the hydrothermal method, both with and without the addition of Na2SiO3 and NaAlO2. This research was conducted to produce synthetic zeolite utilized to remove lead (Pb(II)) through the adsorption process. The temperature of crystal formation (aging) was performed at 60°C for 6 hours, and the hydrothermal process was at 100°C for 24 hours. The resulting synthetic zeolite included the NaP1 and faujasite types. The effects of adsorption parameters, such as pH and contact time, were identified. The best adsorption capacity was demonstrated by synthetic zeolite without the addition of Na2SiO3 and NaAlO2, with a value of144.7191 mg/g at pH 4, with a45 minute contact time. The results showed that the synthesis of zeolite performed by the hydrothermal method could increase the cation exchange capacity (CEC) up to 105.42cmol/kg, from a natural zeolite with aCECof20.14 cmol/kg. The Langmuir model was consistent with an isothermal adsorption equilibrium process, and the adsorption free energy (∆Gads) was consistent with physical adsorption (physisorption). The Nap1 zeolite of Ende-NTT natural zeolite was a better Pb(II) heavy metal adsorbent than the synthetic zeolites of fly ash and coal bottom ash.

No abstract

Oil palm trunk is lower in dimensional stability, density, physical, and mechanical properties than other wood species. Efforts to overcome the weakness of the oil palm trunk properties could be conducted through densification ABSTRAKBatang sawit memiliki stabilitas dimensi, kerapatan, sifat fisik, dan mekanik lebih rendah daripada jenis kayu lainnya. Upaya mengatasi kelemahan sifat batang sawit dapat dilakukan melalui pemadatan (densifikasi) menggunakan kempa panas dan penambahan bahan kimia atau perekat. Tujuan penelitian ini adalah untuk mendapatkan komposisi optimal tanin resorsinol formaldehida (TRF) dalam aplikasinya sebagai bahan perekat untuk peningkatan kualitas batang sawit. Tanin diekstraksi menggunakan air pada suhu 75°C kemudian dikopolimerisasi dengan resorsinol dan formaldehida.

No abstract