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Methylene orange (MO) is a toxic fabric dye to the environment and health. Therefore, some actions are needed to overcome this problem. The advanced oxidation process (AOPs), especially Fenton by hydrogen peroxide (H2O2) and CaO/Fe2O3, is a powerful method to be implemented. In this experiment, the CaO/Fe2O3 was prepared by impregnation using CaO derived from chicken eggshell waste and Fe(NO3)3⸳9H2O powder with calcination temperature variations of 600, 700, and 800°C. Then, the characterization of materials was identified by Fourier Transform Infrared (FTIR), X-ray diffractometer (XRD), scanning electron microscope (SEM), and electron dispersive spectroscopy (EDS), followed by a visual observation decolorization test. Using FTIR and XRD, CaO has been successfully obtained through the calcination process. Fe2O3 was also detected, indicating impregnated into CaO support. The particle size ranges from 37–48 mm, appearing irregular in shape. Finally, the fastest decolorization of MO resulted in CaO/Fe2O3 with 800°C of calcination temperature. These results indicated that CaO/Fe2O3 nanocomposite catalyst is the potential to reduce liquid pollutants and utilize a waste resource.

Heterogeneous fenton , although offering promises for large scale wastewater treatment, is still hindered in its practicality due to its modest catalytic activity. The usage of catalyst supportas been demonstrated previously toecrease the overall particle size to improve its catalytic performance. In this demonstration, fenton catalysts were prepared using the sol-gel method and bacterial cellulose (BC) as catalyst support, with varying sodium hydroxide (NaOH) concentrations (0.01; 0.1 and 1 M). NaCl impurities' presence was successfully eliminated by reducing NaOH concentration relative to the previous 4 M concentration. Lower NaOH concentration leads to a more favorable condition for the formation of smaller non-agglomerated particles and magnetite (Fe3O4) as its main crystalline phase. It was found that the best performing catalyst was produced using 1 M NaOH and was able to degrade Methylene blue solution up to 53.8% remaining dye concentration within two hours.

Pandemi COVID-19 tidak menyurutkan semangat tim pengabdian masyarakat Program Studi Teknik Material dan Metalurgi (TMM) Institut Teknologi Kalimantan (ITK) untuk melaksanakan kegiatan positif dalam rangka meningkatkan kompetensi para pemuda dan pemudi di Indonesia, terutama Kota Balikpapan melalui kegiatan sosialisasi pengenalan 3D printing. Kegiatan ini bertujuan untuk memberikan wawasan mengenai perkembangan teknologi khususnya 3D printing sebagai proses produksi yang lebih canggih dan terkini. Kegiatan ini telah dilaksanakan dengan mengundang pemateri yang sudah berkecimpung langsung di industri 3D printing di Samarinda. Kegiatan ini diikuti oleh 117 peserta yang terdiri dari siswa SMA/SMK serta mahasiswa. Peserta yang mengikuti kegiatan tidak hanya berasal dari Balikpapan namun terdapat juga dari luar Balikpapan seperti dari Mataram, Nusa Tenggara Barat. Sebanyak 71% peserta menyatakan materi sangat menambah wawasan dan 82% peserta menyatakan bahwa materi sangat memberikan manfaat. Kegiatan ditutup dengan pemberian hadiah dan foto bersama.

The accumulation of pollutants in water is dangerous for the environment and human lives. Some of them are considered as persistent organic pollutants (POPs) that cannot be eliminated from wastewater effluent. Thus, many researchers have devoted their efforts to improving the existing technology or providing an alternative strategy to solve this environmental problem. One of the attractive materials for this purpose are metal-organic frameworks (MOFs) due to their superior high surface area, high porosity, and the tunable features of their structures and function. This review provides an up-to-date and comprehensive description of MOFs and their crucial role as adsorbent, catalyst, and membrane in wastewater treatment. This study also highlighted several strategies to improve their capability to remove pollutants from water effluent.

Meranti (Shorea macrobalanos) is a typical wood from Kalimantan that is still valued as a raw material of furniture production. According to statistical data, meranti sawdust waste reached 44% and has not been widely used. It is known that meranti has a high lignocellulose content, which are 38.18% of lignin, 26.03% of hemicellulose and 40.33% of cellulose. Due to the high cellulose level, meranti becomes an alternative source of cellulose which can be applied in composites, biomaterials, and membranes. Therefore, this study aims to produce cellulose from yellow meranti sawdust waste using an alkali treatment, NaOH 17.5%, with a variation of extract time of 20, 40, and 60 minutes. Cellulose characterization was performed using the Chesson-Datta method, Fourier-transferred Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM). The Chesson-Datta test showed that cellulose concentration escalated by increasing process time, which is 45%, 47% and 53% at 20, 40, and 60 minutes respectively. Increased levels of cellulose were followed by decreasing concentrations of lignin and hemicellulose. The FTIR results presented a strengthening of the intensity in the C-O-C functional group which indicated an increase in cellulose levels. Meanwhile, a decrease intensity was also revealed in the aromatic C=C and C=O groups, which implied a reduction in the amount of lignin and hemicellulose. Through the SEM, the surfaces were recognizably less dense by increasing extract time. It is because of the degradation of lignin and hemicellulose. Herein, the most optimum yield was achieved in 60 minutes to produce up to 53% of cellulose. Thus, yellow meranti sawdust waste has a high potential source of cellulose. Keywords: yellow meranti, alkali treatment, cellulose Abstrak Meranti ( Shoreamacrobalanos ) merupakan kayu khas Kalimantan yang saat ini masih dimanfaatkan sebagai bahan baku pembuatan furnitur. Menurut data statistik, limbah serbuk kayu meranti yang dihasilkan mencapai 44% dan belum banyak dimanfaatkan. Telah diketahui bahwa meranti memiliki kandungan lignoselulosa yang cukup tinggi, yaitu 38,18% lignin, 26,03% hemiselulosa, dan 40,33% selulosa. Dengan kandungan selulosa yang tinggi, meranti menjadi salah satu alternative sumber selulosa yang kemudian dapat diaplikasikan di bidang komposit, biomaterial, dan membran. Oleh karena itu, penelitian ini bertujuan untuk menghasilkan selulosa dari limbah serbuk meranti kuning dengan menggunakan metode alkalisasi, NaOH 17,5%, dengan variasi waktu ekstrak selama 20, 40, dan 60 menit. Karakterisasi selulosa dilakukan dengan menggunakan uji Chesson-Datta, fourier-transferred infrared (FTIR), dan scanning electron microscope (SEM). Uji Chesson-Datta menunjukkan semakin lama waktu alkalisasi dapat meningkatkan konsentrasi selulosa, yaitu 45%, 47% dan 53% pada waktu alkalisasi 20, 40, dan 60 menit. Peningkatan kadar selulosa diikuti dengan menurunnya konsentrasi lignin dan hemiselulosa. Hasil FTIR menunjukkan penurunan intensitas pada gugus C=O yang mengindikasikan adanya penurunan jumlah lignin dan hemiselulosa seiring dengan meningkatnya waktu. Hasil morfologi SEM juga menunjukkan permukaan yang semakin tidak rapat seiring dengan meningkatnya waktu alkalisasi. Hal ini diakibatkan terjadi degradasi lignin dan hemiselulosa. Pada penelitian ini, hasil paling optimum dicapai pada waktu 60 menit dengan menghasilkan selulosa hingga 53%. Sehingga, limbah serbuk meranti memiliki potensi sebagai sumber selulosa yang cukup tinggi. Kata kunci: meranti kuning, alkalisasi, selulosa

Heterogeneous fenton catalyst is one of the promising technologies for destruction of persistent and non-biodegradable pollutant in wastewater, such as dyes from textile industries. Previously, bacterial celluloses (BCs) were used as catalyst support of fenton catalysts to improve their catalytic activity. However, reusability of fenton catalyst@bacterial celluloses were not explored yet. Herein, fenton catalyst@bacterial celluloses were prepared using sol gel method with precursor concentration of 0.05 M and characterized by visual observation, Scanning Electron Microscopy (SEM) and UV-Vis spectroscopy. After five cycles of repeated use, catalytic ability of the catalysts was gradually decrease to 17.9% of the original one. Understanding reusability of fenton catalyst@bacterial celluloses will be helpful for wastewater treatment application.

Organic pollutants in water are an increasingly prominent problem. Given this challenge, this study reported the high adorptive removal of methylene blue (MB) onto potassium hydroxide (KOH)-activated carbon. To prepare activated carbon, saba banana peel that are local organic waste were carbonized at 400 ° C and activated using various KOH concentrations, e.g.(0,5, 1 and 1,5 M). Physical and microstructural properties of activated carbon were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), and Fourier Transform Infrared (FTIR). The efffect of KOH concentrations on the adsorption perfromance of MB on KOH-activated carbon were further investigated. The adsorption process occurred more easily after KOH (1,5 M) of concentration and the adsorption capacity of activated carbon improved by more than 23 %. These results indicate that preparing Banana fruit peels-derived activated carbon using KOH activation is an effective way to reduce pollution and utilize a waste resource.