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Role of ammonium phosphate in improving the physical characteristics of malachite sulfidation flotation

Ibrahim Ayman M., Jia Xiaodong, Cai Jinpeng, Su Chao, Yu Xingcai, Zheng Qifang, Peng Rong, Shen Peilun, Liu Dianwen

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 1

art. no. 161510

EN

In this study, ammonium phosphate ((NH4)3PO4) was employed to realize improvement by modifying the physical characteristics of the malachite surface, ensuring sustainable flotation throughout the flotation operations, and enhancing the flotation process to be more stable. Furthermore, various techniques, including X-ray photoelectron spectroscopy, were intensely used to investigate the configuration and physico-chemical surface characteristics through micro-flotation experiments, contact angle and zeta potential measurements, and XRD, ToF-SIMS, EPMA, and FTIR spectrum analyses. The FTIR findings showed that new characteristic peaks of -C(=S)-N.H. groups formed and adsorbed on the surfaces of malachite at 1636 cm-1. The -CH2 groups throughout the flotation process, further promoted the attachment of the CH3 ligand to the Cu2+ ion, and the XPS analysis confirmed this. Consequently, it can be concluded that (NH4)3PO4 played a substantial part in the improved recovery rate, as demonstrated and confirmed by the methods carried out in this study. Thus, it was used to modify the physical properties surface before adding Na2S to efficiently enhance malachite floatability and reduce the loss rate of malachite. Regarding the alterations in the physical characteristics which occurred to the malachite surface, and as a consequence of increasing the recovery results of flotation, the malachite sample treated initially with (NH4)3PO4 exhibited micro flotation results with a considerably greater flotation recovery than malachite treated initially with only Na2S ions.

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The evaluation of rootstock and management practices to counteract replant disease in an apple orchard

Tryngiel-Gać Anna, Treder Waldemar, Klamkowski Krzysztof, Wójcik Katarzyna, Kiełkiewicz Mirosław

Journal of Water and Land Development

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2023

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no. 58

17--24

EN

The aim of the research was to evaluate effects of different rootstocks and management practices to counteracting replant disease in an apple orchard. The experiment was conducted in the Experimental Orchard of the National Institute of Horticultural Research in Dąbrowice, Poland, in 2014-2020. Apple trees of the cultivar ‘Ligolina’ were planted in autumn of 2013 at spacing of 3.8 × 1.4 m in the rows of an apple orchard that had been grubbed up in spring. The following experimental setups were used: (i) two types of rootstocks of different growth vigour (M.9, P14); (ii) replacement of soil in rows of trees with virgin soil; (iii) fertigation with ammonium phosphate; (iv) control (cultivation in the exhausted soil). Replantation significantly limited the growth of apple trees by reducing the cross-sectional area of the tree trunk, and the number and length of annual shoots. Fruit yields of apple trees grown on the replantation site were significantly lower than those of the trees grown in virgin soil. The use of ammonium phosphate fertigation had a positive effect on the growth and yield on the replantation site, especially when it was combined with the use of a stronger-growing rootstock (P14). The most effective environmentally friendly method of eliminating the apple replant disease is the replacement of the exhausted soil with virgin soil, i.e. soil that has not been used for growing fruit trees before.

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Characteristics and Adsorption Test of Activated Carbon from Indonesian Bituminous Coal

Kusdarini Esthi, Budianto Agus

Journal of Ecological Engineering

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2022

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Vol. 23, nr 10

129--138

EN

The fast-growing batik industry in Indonesia raises the problem of the waste containing chromium. One method to remove chromium is by the adsorption process using activated carbon. Activated carbon can be made from coal. This commodity is a mining mineral the availability of which is still abundant in Indonesia. This study aimed to obtain: 1) the best concentration of activator and activation temperature in the manufacture of activated carbon; 2) characteristics of activated carbon (moisture content, volatile matter content, ash content, fixed carbon content, iodine number, specific surface area, pore-volume, pore surface area, pore radius, and SEM photos); 3) % activated carbon removal for chromium and maximum adsorption capacity for chromium; 4) Freundlich and Langmuir isotherm adsorption equation of activated carbon to chromium. The manufacture of activated carbon was carried out by a carbonization process followed by a chemical and physical activation processes. The chemical activator was ammonium phosphate with doses of 74.5 g/L, 149 g/L, 223.5 g/L, and 298 g/L. Meanwhile, physical activation was carried out at 848 K, 948 K, 1048 K, and 1148 K. The next step was to test the adsorption capacity of activated carbon on artificial batik waste containing chromium. The results showed that: 1) activator concentration did not significantly affect the characteristics of activated carbon. Meanwhile, the optimal activation temperature is at a temperature of 1048 K and 1148 K, which can produce the activated carbon that meets the requirements of activated carbon of the Indonesian National Standard 06-3730-1995 with the following contents: air content 0.16–0.81%; volatile matter 14.62–19.31%; ash 6.48–9.97%; fixed carbon 70.60–75.79%; iodine number 1243.13–1258.65%; specific surface area 31.930 m2/g; activated carbon pore volume 0.011 cc/g; pore surface area 8.905 m2/g; activated carbon pore radius 30.614; 3) the proportion of activated carbon removal for chromium is 37–53% and the maximum adsorption capacity for chromium is 52 mg/g; 4) the Freundlich equation test resulted in a constant R2 of 0.5126, n 2.4870, KF 8.8818 mg/g, while the Langmuir equation test resulted in a constant R2 of 0.8897, b -0.0075 L/mg, qm -90.0901 mg/g.

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Flame retardancy of biocomposites based on thermoplastic starch

Bocz K., Szolnoki B., Władyka-Przybylak M., Bujnowicz K., Harakály G., Bodzay B., Zimonyi E., Toldy A., Marosi G.

Polimery

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2013

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T. 58, nr 5

385-394

EN

The flame retardancy of fully biodegradable, natural fiber reinforced thermoplastic starch (TPS) composites was studied in this work. Thermoplastic starch of significantly reduced flammability could be prepared by using a phosphorus containing polyol for plasticizing starch. The thermal degradation of the obtained flame retarded TPS was compared to conventional glycerol-plasticized TPS using not only TGA and DSC but also LP-FTIR (Laser pyrolysis FT-IR coupled method) measurements, which allowed the identification of all the gaseous degradation products. The flame retardant TPS matrix was reinforced with chopped flax fibers and woven linen-hemp fabrics. Due to the embedding of biofibers significant increase in tensile and impact properties of TPS could be achieved, however, the flammability characteristics of the biocomposites, measured by LOI, UL-94 and cone calorimetric tests, become inferior to those of the unreinforced TPS matrix, thus the flame retardant treatment of the reinforcing natural fibers was indispensable. The thermal behaviour and flame retardancy of biofibers, investigated by TGA and cone calorimetry, showed substantial improvement as a consequence of their phosphorous surface treatment. The prepared fully biodegradable biocomposites, comprising of TPS matrix plasticized with P-polyol and P-treated biofibers, exhibit increased mechanical performance accompanied with excellent flame retardancy: pass V-0 rating in UL-94 test, reach LOI of 32 vol. %, and show with 45 % reduced pkHRR during combustion than the unreinforced TPS reference.

PL

Przedmiotem pracy była ocena ognioodporności całkowicie biodegradowalnych kompozytów skrobi termoplastycznej wzmacnianej naturalnymi włóknami. Termoplastyczną skrobię (TPS) o ograniczonej palności otrzymywano stosując w charakterze plastyfikatora poliol zawierający fosfor. Porównano przebieg degradacji termicznej uniepalnionej TPS z degradacją termiczną skrobi uplastycznionej konwencjonalnie przy użyciu glicerolu, stosując metody TGA, DSC oraz LP-FTIR, umożliwiające identyfikację wszystkich gazowych produktów rozkładu. Uniepalnioną matrycę skrobi termoplastycznej wzmacniano ciętymi włóknami lnu lub warstwami tkaniny lniano-konopnej. Dzięki wzmocnieniu osiągnięto znaczne zwiększenie wytrzymałości na rozciąganie oraz udarności wytworzonych biokompozytów, jednak ich odporność na palenie [oceniana na podstawie indeksu tlenowego (LOI), testu UL-94 oraz za pomocą kalorymetru stożkowego] uległa znacznemu pogorszeniu w stosunku do ognioodporności niewzmacnianej skrobi termoplastycznej. Badania TGA oraz metodą kalorymetru stożkowego wykazały, że udział fosforu w zastosowanym plastyfikatorze, a także we włóknach naturalnych modyfikowanych związkami fosforu użytych jako wzmocnienie, wpływa na poprawę odporności na ogień wytworzonych biokompozytów (klasa palności V-0 w teście UL-94, indeks tlenowy 32 %, maksymalna szybkość wydzielania ciepła mniejsza o 45 % niż w przypadku niewzmacnianej TPS), a jednocześnie pozwala na zachowanie ich korzystnej wytrzymałości mechanicznej.