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Solid-State Mechanochemical Synthesis of Kaolinite-Urea Complexes for Application as Slow Release Fertilizer

AlShamaileh Ehab M., Al-Rawajfeh Aiman E., Alrbaihat Mohammad R.

Journal of Ecological Engineering

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2019

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Vol. 20, nr 9

267--276

EN

This study investigated a mechanochemical (MC) process for synthesizing a slow-release urea fertilizer by cogrinding the starting materials of (NH2)2CO and amorphous kaolinite in a planetary ball mill. The tests with kaolinite contents ranging from 25 to 75 wt. %, milling time ranging from 1 (h) to 3 (h) and mill rotational speeds from 200 to 700 rpm were performed to evaluate the incorporation of (NH2)2CO and release of nitrogen into the solution. The analyses conducted using XRD, TGA, FT-IR and KNDU (Kjeldahl Nitrogen Determination Unit) indicated that the MC process was successfully applied to incorporate (NH2)2CO into the amorphous kaolinite structure. The release of nitrogen from the system (kaolinite-(NH2)2CO) when dispersed in water for 24 h reached up to 20% at 25% wt of kaolinite. Moreover, under the milling speed conditions for the system (kaolinite–(NH2)2CO), release of nitrogen reached between 25 and 40%. These results indicated that the MC process can be developed to allow amorphous kaolinite to act as a carrier of nitrogen nutrients to be released slowly for use as fertilizer.

2

Biodegradable polymer composites with nitrogen- and phosphorus-containing waste materials as the fillers

Treinyte J., Grazuleviciene V., Ostrauskaite J.

Ecological Chemistry and Engineering. S

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2014

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Vol. 21, nr 3

515--528

EN

Composites consisting of polyvinyl alcohol, nitrogen- and phosphorus-containing waste materials were prepared and studied as materials for encapsulation of mineral fertilizers By-products of biodiesel production (rapeseed cake, crude glycerol), horn meal (waste product of haberdashery) and phosphogypsum (by-product of the production of phosphorus fertilizers) were used as the fillers of the composites. The films of the composites with the different amounts of nitrogen and phosphorus were prepared using different fillers or their mixtures. Mechanical, properties of the films, hygroscopicity, solubility in water were studied. The composites developed were used for the encapsulation of mineral fertilizers. It was established that encapsulation resulted in the increase of the time of release of the fertilizers. The developed slow-release fertilizers represent a combination of inorganic and organic compounds. The organic part consists of nitrogen- and phosphorus containing horn meal and rapeseed cake. Since assimilation of organic substances is considerably longer, nitrogen and phosphorus of these components will be available for plants much later than inorganic nitrogen and phosphorus. Thus the composite film will not only decrease the rate of desorption of the components from the granules of the fertilizers but will also prolong the impact of the fertilizers on the plants.

PL

Wytworzono materiały kompozytowe, składające się z alkoholu poliwinylowego, zawierające odpady z azotem i fosforem. Badano możliwości zastosowania tych materiałów do kapsułkowania nawozów mineralnych. Jako wypełniacze kompozytów były wykorzystywane produkty uboczne wytwarzania biopaliwa do silników wysokoprężnych (makuch rzepakowy, surowy glicerol), mączka rogowa (produkt odpadowy z produkcji pasmanteryjnej) i fosfogips (produkt uboczny produkcji nawozów fosforowych). Wytworzono folie kompozytowe z różnymi ilościami azotu i fosforu, różnymi wypełniaczami lub ich mieszaninami. Badano właściwości mechaniczne folii, ich higroskopijność i rozpuszczalność w wodzie. Otrzymane kompozyty zostały wykorzystane do kapsułkowania nawozów mineralnych. Stwierdzono, że kapsułkowanie spowodowało zwiększenie czasu uwalniania nawozów. Opracowane nawozy powolnego uwalniania stanowią kombinację związków nieorganicznych i organicznych. Organiczna część składa się z mączki rogowej i makucha rzepakowego, zawierających azot i fosfor. Ponieważ asymilacja substancji organicznych jest znacznie dłuższa, azot i fosfor z tych składników będą dostępne dla roślin znacznie później niż z substancji nieorganicznych. W ten sposób folia z kompozytu nie tylko zmniejszy szybkość desorpcji składników z granulek nawozów, ale również przedłuży wpływ nawozów na rośliny.

3

Inteligentne nawozy

Tomaszewska M., Jarosiewicz A.

Chemik

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2006

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Vol. 59, nr 6

328-328

PL

Przedstawiono grupę nawozów określanych mianem preparatów o spowolnionym, kontrolowanym uwalnianiu składników odżywczych (SRF/CRF). Opisano ich klasyfikację i metody produkcji. Szczególną uwagę zwrócono na mechanizmy uwalniania składników odżywczych z poszczególnych grup nawozów. Przedstawiono również zastosowanie nawozów o kontrolowanym uwalnianiu w praktyce oraz różnorodność produktów typu SRF/CRF dostępnych na rynku.

EN

Agrochemicals, described as slow- or controlled-release fertilizers (SRF/ CRF), were presented. The classification and methods for their production was described. Special attention was devoted to the description of a mechanism of the nutrients release. The use of slow- and controlled-release fertilizer in practice and the available types was presented too.

4

Textile slow-release systems with medical applications

ten Breteler M. R., Nierstrasz V. A., Warmoeskerken M. M. C. G.

Autex Research Journal

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2002

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Vol. 2, no. 4

175--189

EN

In the development of medical drug delivery systems, attention has been increasingly focused on slow- or controlled delivery systems in order to achieve an optimal therapeutic effect. Since the administration of drugs often requires a defined or minimum effective dosage in the human body, more conventional delivery systems such as tablets require relatively high doses, which can result in undesired toxic effects. Subsequent degradation of the drug in the human body will result in a drug concentration below the minimum effective level. Furthermore, there are situations where oral administration is less advisable, such as in cases of prolonged treatment or with people that are forgetful, which again results in ineffective treatment. Textile slow-release systems have the potential to overcome these negative aspects. Drugs containing transdermal patches for ex-vivo applications are already familiar; however, this paper will not deal with such applications, but with more advanced in-vivo textile slow-release systems. Due to enormous progress over the years in the fields of supramolecular chemistry, nanotechnology, and polymer science & technology, a number of promising drug delivery technologies have been developed. This review will focus on the opportunities of textiles bearing cyclodextrins, aza-crown ethers or fullerenes, as well as ion-exchange fibres, drug-loaded hollow fibres, textiles treated with nanoparticles and fibres with bioactive compounds in their embodiment. In this paper, the delivery systems will be discussed and compared in terms of biostability, biodegradability, controllability, toxicity, carcinogenicity, interface reactions, material costs and the fabrication process.