Industrial wastewater contains non-biodegradable dyes that are highly toxic to humans and aquatic life. As solution from photocatalytic degradation, TiO₂ is one of the effective photocatalysts for wastewater degradation, but it has low adsorption power. To overcome this deficiency, this study synthesized a new photocatalyst by Fe-TiO₂/zeolite H-A. The photocatalyst was successfully synthesized by the impregnation method and was systematically characterized by XRD, XRF, SEM, FT-IR and UV-Vis DRS. XRD diffractogram at 2θ = 25.3° showed anatase phase of the photocatalyst. SEM results showed a rough and soft surface with a size of 491.49 nm. FT-IR analysis obtained the zeolite-A characteristic band, vibration of Ti-O-Ti groups and the vibration of the Fe-O group. The bandwidth of the band gap was 3.16 eV. The photocatalytic efficiency of methylene blue degradation reached 89.58% yield with optimum conditions: irradiation time of 50 min, pH 9 and concentration of methylene blue about 20 mg/L. Fe-TiO₂/zeolite H-A as a new photocatalyst can be an alternative photocatalyst to purify methylene blue.

The objectives of this study are to investigate the effectiveness of activated zeolite with and without impregnated Ag on the conversion of glycerol to ethanol. Zeolite catalyst used in this study was synthesized zeolite from silica extracted from local sand and glycerol conversion using zeolite with and without impregnated Ag done at various temperatures of sonication. Product conversion analyzed using Gas Chromatography. The results showed that the impregnation of g on the activated zeolite catalyst increase the acidity from 0.0774 to 3.6253 mmol/g. The surface area slightly decreases from 1339 becomes 1279 m²/g. The process of converting glycerol to ethanol, the use of ultrasonic waves increases the effectiveness of glycerol conversion. The higher the sonication temperature, the greater ethanol produced. The highest ethanol product with a yield of 13.6% was obtained at a sonication temperature of 60 °C when the active Ag/zeolite catalyst was used. The use of Ag/zeolite catalyst makes glycerol conversion can be carried out at relatively low temperatures and ambient pressures so that it has more promising future prospects.

Biodiesel from natural materials has proven its contribution as a renewable energy source. Exploration of natural materials has expanded until many studies have begun to consider natural waste materials to reduce the impact of environmental damage. A natural material that is still considered waste is Crude Palm Oil (CPO) Low/Off Grade. Research on this waste has begun to be projected as a raw material for biodiesel. Research on the use of various catalysts in the transesterification and esterification reaction of this waste has expanded. Then, the biodiesel produced has unique characteristics. Thus, some of these studies have been reviewed on a small scale. From that, it is proposed a route to utilize CPO Low/Off Grade which is sustainable and renewable. Therefore, this review article aims to provide a unique understanding of research on the use of Low/Off Grade CPO as biodiesel. DOI: http://dx.doi.org/10.17807/orbital.v13i4.1632

The purpose of this study was to synthesize NaY zeolite by utilizing local sand as a source of silica which was carried out at various crystallization temperatures. The synthesis of NaY zeolite is carried out using silica resulted from the purification of local sand while NaOH and Al₂O₃ are pure analysis (pa) quality. Crystallization temperature was carried out at various temperatures of 80, 100, and 150 °C. The synthesis results were characterized by physical properties, XRF, FTIR, XRD, SEM, surface area. NaY zeolite was successfully synthesized supported by FTIR data by the presence of functional groups such as Si-O, O-Al-O, Si-OH, and O-H from Si-OH, and SEM data which showed the formation of cube-shaped crystals. The formation of NaY zeolite is also strengthened by the appearance of peaks with a sharp intensity from XRD diffractogram that this zeolite is NaY and as well as data molar ratio of Si/Al is in the range of 2.027 to 2.045 respectively at various crystallization temperature. The crystallization temperature of 80 °C produces NaY zeolite better than that of crystallization temperatures of 100 and 150 °C. The synthesized NaY zeolites using local sand have a good surface area that is 658 m²/g. The crystallization temperature affects the success of NaY zeolite synthesis.

Kapok seed oil is an environmentally friendly biodiesel feedstock. The problem of the best catalyst for transesterification of Kapok seed oil still continues today. The research developed a base-heterogeneous catalyst with the effect of ultrasonic waves during transesterification. So, the study aims: (1) to determine the type of natural zeolite used, (2) to determine the characteristics of the synthesized CaO:BaO/ANZ catalyst, and (3) to determine the effectiveness of the CaO:BaO/ANZ catalyst in the biodiesel production process through sono-transesterification of kapok seed oil. The research stages consisted of: (1) activation of natural zeolite and its characterization, (2) preparation of CaO:BaO/ANZ catalyst, (3) characterization of CaO:BaO/ANZ catalyst, (4) esterification and utilization of catalyst in the transesterification, (5) analysis of transesterified products. The results showed that the natural zeolite type from the southern area of Malang is mordenite (MOR) type. Then, after the natural zeolite was impregnated, the obtained catalyst compositions were CaO:BaO-9:9/ANZ, CaO:BaO-14:9/ANZ, and CaO: BaO-4:11/ANZ with a surface area of 129.7; 124.6; 128.5 m² /g, and acidity of 1.037; 0.254; and 0.685 mmol/g, respectively. The best catalyst for transesterification of kapok seed oil was CaO:BaO-9:9/ANZ, which resulted in a biodiesel yield of 73.6% with a density of 889.6 kg/m³ and kinematic viscosity of 2.987 cSt. The characteristics of the produced biodiesel meet requirement of SNI 7182:2015.

Natural zeolite from Malang Regency is a raw material that can be used as an adsorbent for heavy metal waste. However, this natural zeolite needs activation and optimization to be utilized maximally as an adsorbent. This study was conducted for both physical and chemical activation of natural zeolite. Characterization results of XRD indicated that the natural zeolite possesses crystalline phases and is of the mordenite type. Based on the XRF results, the Si/Al ratio increased from 5.768 to 6.119 after activation. Based on the characterization results using the BET method with SAA analysis, the surface area of non-activated natural zeolite was determined to be 20.8045 m²/g, while activated natural zeolite had a surface area of 137.8196 m²/g. Results of the adsorption study in treating liquid laboratory waste using simulated Pb and Cr metal wastes demonstrated that activated natural zeolite performed more effectively as an adsorbent than non-activated natural zeolite. The adsorbent’s optimum mass was 0.3 grams, resulting in an adsorption percentage of 97.43% for Pb and 97.56% for Cr, with a contact time of 30 minutes at pH 6. The adsorption kinetics of Pb and Cr metals were described using a pseudo-second-order rate equation. The adsorption of Pb and Cr was depicted using the Langmuir equation, indicating the monolayer formation on the homogenous adsorbent surface during the adsorption process. The activated natural zeolite has the potential to be employed as an independent adsorbent in the treatment of heavy metal waste.