In this report, we prepared activated charcoal from oil palm midrib and used it as an adsorbent to decolorizeReactive Red and Direct Green as synthetic dyes in the sample solution. The response of various experiments conditions, such as contact time, solution pH, temperature, the weight of adsorbent, and concentration of dyes, on adsorption of synthetic dyes, were evaluated along with the analysis of isotherms, kinetics, and thermodynamics adsorption parameters. At equilibrium, adsorption of dyes onto activated charcoal fitted well to Freundlich model giving coefficients of correlation R 2 ≥ 0.9. At optimum conditions, capacities of adsorption for Reactive Red 120 and Direct Green 26 were 151 and 116 mg/g, respectively. The kinetics study suggested that dyes adsorption onto activated charcoal followed the model of pseudo-second-order with thermodynamic parameters of ∆G°, ∆H°, and ∆S° were -0.21 to -3.93 kJ/mol, -30.15 to -36.12 kJ/mol, and 0.003 J/mol.K, respectively. Based on the experiments, we conclude that dyes adsorption was exothermic, spontaneous and an increase in the system entropy. The results of FT-IR analysis indicated the involvement of various functional groups, including hydroxyl and amine groups. This study emphasizes the potential of oil palm waste as an alternative low-cost adsorbent for the removal of dyes.

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Synthesis of composite material based on sulfonated polystyrene and bacterial cellulose as a proton membrane has been carried out. In this study, the membrane was made with the variations mass ratio of sulfonated polystyrene : bacterial cellulose 1,5: 3,5, 2,5: 2,5, 3,5: 1,5. The previous step was sulfonation of polystyrene, in which the polystyrene used is styrofoam from electronic goods packaging waste. Polystyrene in this case styrofoam is sulfonated using the sulfonating agent trimethylsilyl chlorosulfonate. The membranes have characterized by analyzing of functional groups, proton conductivity, cation exchange capacity, and degree of swelling. The FTIR spectrum showed that the sulfonated polystyrene-bacterial cellulose composite material was successfully synthesized which was shown at the peak at wave number 1124.767 cm−1 which was a SO3 stretching vibration. The peak at wave number 962-1150 cm−1 was assigned the stretching of CO vibrations for C-OC and C-OH which indicates cellulose glycosidic bonds. The highest Cation Exchange Capacity (CEC) value and proton conductivity were in the composite membrane: bacterial cellulose mass ratio 3,5: 1,5, the CEC value 2.25 meq/g and the proton conductivity value 1.176 x 10−6 S/cm2. This result shows that the sulfonated polystyrene-cellulose bacterial composite membrane has the ability to deliver protons so that it has the potential to be developed as a fuel cell membrane.

Kelangkaan dan kenaikan harga LPG menyebabkan masyarakat Desa Sukasari kembali beralih ke kayu bakar untuk keperluan memasak sehari-hari. Padahal Desa Sukasari mempunyai potensi yang besar berupa limbah kotoran sapi yang dapat digunakan sebagai penghasil gás. Melihat potensi ini maka penting dilakukan pelatihan pembuatan dan pengoperasian instalasi biogás sistem kontinu pada masyarakat Desa Sukasari dengan memanfaatkan kotoran sapi. Pelatihan dilaksanakan pada Kelompok Tani Harapan Maju sebagai contoh bagi masyarakat Desa Sukasari yang lainnya. Pelatihan dilakukan dengan metode ceramah dan pembuatan langsung instalasi biogas. Kegiatan pelatihan berhasil dilaksanakan yang ditandai dengan kemampuan mitra membuat instalasi biogas dan gas yang dihasilkan telah dimanfaatkan untuk memasak. Berdasarkan informasi mitra, gas yang terbentuk dengan kapasitas digester 500 L dengan pengisian feed ±15 L/hari dapat digunakan untuk memasak selama ±0.5 jam.