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The degree of complexation of microelement ions by the biodegradable chelating agent - IDHA was examined in the work. The tests were carried out in water and in a simulated fertilizer environment. In order to compare the obtained results, tests were also carried out for the commonly used EDTA. The performed analyzes allow to determine the influence of the presence of compounds containing macroelements on the degree of binding of microelement ions by the biodegradable IDHA and EDTA chelators. The obtained results make it possible to determine the optimal conditions for the chelation of cations by IDHA, which in the future may be used in the production of micronutrient fertilizers on a large scale. [ABSTRACT FROM AUTHOR]

The degree of zinc complexation was related to the type of the chelating agent and to the pH, whereas the stability of the zinc complexes was examined according to the chelating agents chosen from the group of aminopolycarboxylates. The degree of zinc complexation by the chelating compounds of the aminopolycarboxylates [ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), N-(hydroxyethyl)ethylenediaminetriacetic acid (HEEDTA), nitrilotriacetic acid (NTA), S,S-ethylenediaminedisuccinic acid (S,S-EDDS), methylglycinediacetic acid (MGDA), glutamic acid diacetic acid (GLDA)] in the environment of the supporting electrolyte was determined by differential pulse voltammetry using a mercury electrode operating in the SMDE mode. Reference electrode was silver-chloride electrode and auxiliary electrode was glassy carbon electrode. Voltammetric researches were carried out on the AUTOLAB PGSTAT 12 (Eco Chemie - The Netherlands) with GPES software with the use of mercury electrode 663 VA Stand (Metrohm - Swiss). The degree of zinc complexation increased with the increase in the concentration of the chelating agent and with the rise in the pH. Zinc complexes with EDTA, HEEDTA, DTPA and S,S-EDDS preserved their stability with time elapsed. [ABSTRACT FROM AUTHOR]

• Potassium salts influence phase transitions of ammonium nitrate. • Potassium chloride accelerates and amplifies the exothermic decomposition. • Carbonates and metabisulfite are too reactive for industrial use. • Potassium phosphates, nitrate and sulphate inhibit the decomposition. • Small amounts of salts tend to worsen thermal stability of ammonium nitrate. Ammonium nitrate (AN) has proven to be an unstable and hazardous component of mineral fertilizers. In order to analyze the influence of various potassium salts on thermal properties of ammonium nitrate, differential thermal analysis coupled with thermogravimetry and mass spectrometry was used. Each potassium salt was mixed with AN to create samples with AN:salt mass ratios of 4:1, 9:1 and 49:1. It was concluded that an addition of potassium influences phase transitions of AN. Depending on the salt used, an exothermic decomposition of AN was either accelerated (potassium chloride) or inhibited to the varying degree. Carbonate salts and potassium metabisulfite were too reactive to be used in a fertilizer production, while nitrate, sulphate and both phosphates are considered to be appropriate additives and could be used in a multicomponent fertilizer production. [ABSTRACT FROM AUTHOR]

Due to numerous and valuable properties of humic substances, preparations produced from alternative organic materials have been widely used in agriculture, bioremediations, dietary supplements and others. In addition to well-known humic acids, fulvic acids (FA) are a valuable product with a wide range of applications. The aim of performed examinations was to assess the thermal and physicochemical properties of FA obtained from lignite and peat using simplified conventional and ultrasound-assisted methods. DSC coupled with TG and MS, 13C NMR, FTIR spectroscopy and differential pulse voltammetry has been used to examine extracted FA. Depending on the source of FA and the extraction method applied, their structure and properties differ. Obtained FA fractions varied for both tested raw materials in terms of analyzed carbon structures, and the highest discrepancy was observed for carbonyl groups (20.2 pp) in fractions obtained by conventional extraction. The use of the ultrasound-assisted extraction (UAE), in comparison with the traditional method, lowered the ratio of carbon in carbonyl groups by 8.4 pp and increased the ratio of aromatic and aliphatic carbon by 3.5 and 4.9 pp, respectively, for FA obtained from lignite. As for FA obtained from peat, the UAE effect appeared to be less impactful in terms of structural changes. Thermal analysis showed that the products were thermally stable up to 100 °C, and the simplified extraction resulted in the creation of mineral-organic structures that decomposed at unusually high temperatures. Simplifying the extraction process, by excluding inorganic purification and protonation of obtained FA fractions, greatly affects product quality and limits its possible application. [ABSTRACT FROM AUTHOR]

Fertilisers containing ammonium nitrate are the most efficient sources of nitrogen used in agriculture. The major hazard associated with production, storage and transport of materials containing this compound is its liability to rapid decomposition, or even detonation under certain conditions. Properly selected calcium and magnesium carbonates may increase the thermal stability of ammonium nitrate. The aim of this research was to determine the influence of the carbonate mineral type and composition on phase transitions and decomposition process of fertiliser-grade ammonium nitrate. The article focuses on the methodology of thermal analysis of samples containing ammonium nitrate with carbonates and points out the phenomena and thermal characteristics that should be taken into consideration when testing fertiliser mixtures. Two different sample preparation methods allowed for investigating processes that may occur in inappropriate storage and transport conditions as well as during the production of fertiliser. The measurements were taken using techniques of differential thermal analysis and thermogravimetry coupled with mass spectrometry. The results showed that too high a level of carbonates reactivity can cause problems during the production of fertiliser, reducing the effectiveness of the filler in a final product. [ABSTRACT FROM AUTHOR]

Results of efficiency of obtaining humic substances (HSs) from peat in traditional alkaline extraction (TAE) and ultrasound-assisted alkaline extraction (UAAE) are presented. The influence of the duration of the process and ultrasound intensity on the efficiency of extraction of humic acids (HAs) and fulvic acids (FAs) extraction was determined. The composition of the fulvic acid fraction was examined depending on the type of eluent used. Fulvic acids were divided into fractions using columns packed with DAX-8 resin. For this process, 0.1 M NaOH and 0.5 M NH3∙H2O were used as eluents. For the quality assessment of specific fulvic acids fractions, spectroscopic methods (UV-Vis and FTIR) were used. Ultrasound had a positive effect on HS extraction efficiency, especially in increasing the amount of a desired hydrophobic fraction of fulvic acids (HPO). However, a negative effect of the excessive prolongation and ultrasound intensity (approximately 400 mW∙cm−2) on the extraction efficiency of HPO eluted with 0.1 M NaOH solution was observed. Using peat as a raw carbon material for the HS extraction process can be used as an alternative industrial application of peat. UAAE may be considered as an alternative method to TAE, which provides a higher efficiency in HS isolation from peat. [ABSTRACT FROM AUTHOR]

Ammonium nitrate (AN) is considered to be a very hazardous and difficult to handle component of mineral fertilizers. Differential thermal analysis coupled with thermogravimetry and mass spectrometry was used to determine the possible inhibiting effect of selected magnesium compounds on thermal decomposition of AN. Each additive was mixed with AN to create samples with AN:magnesium compound mass ratios of 4:1, 9:1 and 49:1. Most of analyzed compounds enhanced thermal stability of ammonium nitrate, increasing the temperature of the beginning of exothermic decomposition and decreasing the amount of generated heat. Magnesium chloride hexahydrate was determined to accelerate the decomposition of AN while magnesium sulphate, sulphate heptahydrate, nitrate hexahydrate together with magnesite and dolomite minerals were defined as inhibiting agents. [ABSTRACT FROM AUTHOR]

The present study examines the impacts of dry mass content in pig liquid manure on its treatment with a filtration method. Samples of liquid manure with variable dry mass content were subjected to treatment using phosphoric acid, sulfuric acid, lime milk and superphosphate, as well as to thermal treatment, while in the last phase of pressure filtration. Increased dilution of the manure resulted in a reduced raw materials consumption ratio and improved filtration process efficiency, which ranged from 408 to 3765 kg/m2/h. The highest filtration efficiency was achieved using manure containing 3% dry mass, while the lowest efficiency was observed in manure at 10% dry mass. The increase in liquid manure dilution also reduced chemical oxygen demand in the filtrate, which ranged from 15 062 to 3656 mg/l. An appropriate manure dilution level, under the constant parameters of the treatment process, reduced phosphorus content in the filtrate to < 10 mg/kg while simultaneously enriching the post-filtration sediment with this precious fertilizing component. [ABSTRACT FROM AUTHOR]

Granular fertilizers (especially those based on ammonium nitrate (AN)) tend to agglomerate during storage. The aims of this research were to develop effective anti-caking coatings for ammonium nitrate fertilizers while improving the quality of fertilizers and to optimize the composition of effective anti-caking coatings. The influence of the composition of the prepared organic coatings on the effectiveness of preventing the caking of fertilizers was studied by response surface methodology (RSM) using Box–Behnken design (BBD). Additionally, the effect of the developed anti-caking agents on the quality of fertilizers was determined by measuring the crushing strength of the granules. The prepared coatings included fatty amine, stearic acid, surfactant, and paraffin wax. Gas chromatography–mass spectrometry (GC–MS) was used to analyze these coatings. The morphology of the fertilizers were examined by scanning electron microscopy (SEM). Composition studies, based on statistical assessment, showed the coating components had a varying influence on preventing the caking of fertilizers after granulation and after 30 days of storage. The results demonstrated that increasing the content of fatty amines and reducing surfactant in the composition of coating had positive effects on caking prevention. In this study, more effective and economically viable anti-caking coatings were developed. In addition, the present work could serve as a basis to further improve anti-caking coatings. [ABSTRACT FROM AUTHOR]

In application conditions, the influence of environmental parameters on used fertilizer chelates and their distribution over time is important. For this purpose, the changes in the content of micronutrient ions and Fe-EDDHA and Fe-EDDHSA chelates in an aqueous medium at different pH values were studied. In the assumed time, changes in the ions content were analyzed using the voltammetry method at pH 3, 5 and 7. The content of isomers and chelate forms was analyzed by ion pair chromatography at pH 3, 5 and 7. These studies allowed us to determine the effect of pH on the stability of iron chelates over time. [ABSTRACT FROM AUTHOR]

Phosphate fertilizers are most commonly obtained from wet phosphoric acid, which contains a majority of impurities that were present in raw materials used during the production process. It is essential to limit heavy metal contents, including cadmium, in manufactured phosphoric acid for environmental protection purposes. This work investigates kinetics of cadmium removal from wet phosphoric acid by precipitation method. Precipitating agents used in this study are: zinc ethylphenyldithiocarbamate (ZnEPDTC), sodium ethylphenyldithiocarbamate (NaEPDTC), sodium cellulose xanthate (SCX), sodium dibutyldithiocarbamate (NaDBDTC) and sodium sulfide (Na 2 S). For each agent, a proper cadmium reaction model is fitted, the simplified kinetic mechanism is proposed and pseudo-kinetic parameters are derived. Analysed precipitating agents were found to perform following three different mechanisms – ZnEPDTC and NaEPDTC did not react with cadmium ions in investigated conditions, SCX and NaDBDTC were decreasing the concentration of cadmium ions over time and Na 2 S initially decreased cadmium concentration to almost zero and then created Cd(HS) x 2−x complexes. • ZnEPDTC and NaEPDTC did not react with cadmium in investigated conditions. • SCX and NaDBDTC were both efficient cadmium removing agents. • Na 2 S decreased Cd conc. to values near zero immediately after applying to the system. • CdS precipitate dissolved in the presence of H 2 S. • Each precipitating agent performed with different reaction mechanism. [ABSTRACT FROM AUTHOR]