Highly Efficient Photocatalyst Fabricated from the Chemical Recycling of Iron Waste and Natural Zeolite for Super Dye Degradation

In this paper, Fe2O3 and Fe2O3-zeolite nanopowders are prepared by chemical precipitation utilizing the rusted iron waste and natural zeolite. In addition to the nanomorphologies; the chemical composition, structural parameters, and optical properties are examined using many techniques. The Fe2O3-zeolite photocatalyst showed smaller sizes and higher light absorption in visible light than Fe2O3. Both Fe2O3 and Fe2O3-zeolite are used as photocatalysts for methylene blue (MB) photodegradation under solar light. The effects of the contact time, starting MB concentration, Fe2O3-zeolite dose, and pH value on photocatalytic performance are investigated. The full photocatalytic degradation of MB dye (10 mg/L) is achieved using 75 mg of Fe2O3-zeolite under visible light after 30 s, which, to the best of our knowledge, is the highest performance yet for Fe2O3-based photocatalysts. This photocatalyst has also shown remarkable stability and recyclability. The kinetics and mechanisms of the photocatalytic process are studied. Therefore, the current work can be applied industrially as a cost-effective method for eliminating the harmful MB dye from wastewater and recycling the rusted iron wires.

The effectiveness of the use of natural minerals of the Terbunskoye deposit and organic waste in the cultivation of rapeseed

The aim of the study was to assess the effectiveness of the effect of natural nanoporous minerals together with organic waste from poultry farms on the yield of spring rapeseed, qualitative analysis of seeds and obtained samples of rapeseed oil. The experiments were carried out in 2019-2021 in the experimental field of the Yelets State University named after I.A. Bunin. The object of the study was the Rif spring rape variety. The highest productivity was observed in the variants with the introduction of zeolite (3 t / ha) in combination with organic waste 5 t / ha and 10 t / ha, which amounted to 34.4 c / ha and 34.9 c / ha, respectively. These options provided the maximum gross yield of protein (9.74 c / ha and 9.95 c / ha) and oil (13.95 c / ha and 14.10 c / ha). A positive effect from the use of natural zeolite as a fertilizer on the accumulation of oleic acid in the obtained rapeseed oil samples has been established. Keywords: SPRING RAPE, ZEOLITES, ORGANIC WASTE, YIELD, OIL QUALITY

Pengolahan Limbah Cair Batik Banten secara Koagulasi Menggunakan Tawas dan Adsorpsi dengan Memanfaatkan Zeolit Alam Bayah

The batik industry produces liquid waste from the coloring, washing and rinsing processes. This study was aimed to analyze the quality of Banten batik effluent before and after treatment. The processing is carried out using an experimental method with a batch system by coagulation using alum and adsorption using Bayah's natural zeolite by performing 3 variations of coagulant mass and adsorbent for the dye test parameters, TDS and TSS. The results of the test before treatment were the results for dyes of 344 TCU, TDS 620 mg/L, and TSS 218.5 mg/L. Based on the coagulation treatment using alum, the most efficient coagulant results were obtained to reduce the levels of dyestuffs and TDS, namely by using alum coagulant as much as 1500 mg/L which resulted in 96.6 TCU and 330.0 mg/L respectively, then to reduce TSS levels obtained an efficient coagulant that is 500 mg/L with a yield of 10 mg/L. The adsorption treatment using Bayah natural zeolite can reduce the levels of TDS and TSS with the most efficient results using an adsorbent of 150 g/L obtained for TDS 189.3 mg/L and TSS 13.3 mg/L. So based on the results of processing using coagulation and adsorption methods, it is hoped that the batik industry can apply it in processing the liquid waste produced.

Physical Characterisation of a Natural Zeolite using a Scanning Electron Microscopy: A Preliminary Study

Zeolite is one of important non-metallic mineral deposites in Indonesia. It has been used for various purposes, including as an adsobent in environmental protection, industry, and agriculture. The most important characteristics of zeolit to be an adsorbent is its surface area and crystal structure. To optimally use zeolite as an adsorbent, it is necessary to understand its physical characteristics. This preliminary study was aimed to characterize physical properties of a natural zeolite obtained from Tasikmalaya, West Java, Indonesia. The zeolite material was crushed into <0.5 mm diameter and divided into two sets of samples. One set of samples was heated in a muffle furnace at 250 oC for two hours and the other set was left untreated. All samples were then observed using a Scanning Electron Microscopy (SEM). The SEM micrographs showed rough and porous structure and defined crystallinity of the zeolite. Thermal treatment at 250 oC increased zeolite crystallinity. These results confirm that this natural zeolite is potential to be used as an adsorbent to remove dissolved metals from acid mine drainage.

Recycling Rusty Iron with Natural Zeolite Heulandite to Create a Unique Nanocatalyst for Green Hydrogen Production

Corrosion-induced iron rust causes severe danger, pollution, and economic problems. In this work, nanopowders of Fe2O3 and Fe2O3/zeolite are synthesized for the first time using rusted iron waste and natural zeolite heulandite by chemical precipitation. The chemical composition, nanomorphologies, structural parameters, and optical behaviors are investigated using different techniques. The Fe2O3/zeolite nanocomposite showed smaller sizes and greater light absorption capability in visible light than Fe2O3 nanopowder. The XRD pattern shows crystalline hematite (α-Fe2O3) with a rhombohedral structure. The crystallite sizes for the plane (104) of the Fe2O3 and Fe2O3/zeolite are 64.84 and 56.53 nm, respectively. The Fe2O3 and Fe2O3/zeolite have indirect bandgap values of 1.87 and 1.91 eV and direct bandgap values of 2.04 and 2.07 eV, respectively. Fe2O3 and Fe2O3/zeolite nanophotocatalysts are used for solar photoelectrochemical (PEC) hydrogen production. The Fe2O3/zeolite exhibits a PEC catalytic hydrogen production rate of 154.45 mmol/g.h @ 1 V in 0.9 M KOH solution, which is the highest value yet for Fe2O3-based photocatalysts. The photocurrent density of Fe2O3/zeolite is almost two times that of Fe2O3 catalyst, and the IPCE (incident photon-to-current conversion efficiency) reached ~27.34%@307 nm and 1 V. The electrochemical surface area (ECSA) values for Fe2O3 and Fe2O3/zeolite photocatalysts were 7.414 and 21.236 m2/g, respectively. The rate of hydrogen production for Fe2O3/zeolite was 154.44 mmol h−1/g. This nanophotocatalyst has a very low PEC corrosion rate of 7.6 pm/year; it can retain ~97% of its initial performance. Therefore, the present research can be applied industrially as a cost-effective technique to address two issues at once by producing solar hydrogen fuel and recycling the rusted iron wires.