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Nitrogen (N) losses from conventional fertilizers in agricultural systems are very high, which can lead to serious environmental pollution with economic loss. In this study, innovative slow-release fertilizers were prepared using zinc (Zn) [nanoparticles (NPs) or in bulk], using molasses as an environmentally friendly coating. Several treatments were prepared using Zn in different concentrations (i.e., 0.25%, 0.5%, and 4% elemental Zn). The zinc oxide nanoparticles (ZnO-NPs) were prepared from zinc sulfate heptahydrate (ZnSO4·7H2O), and were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the Zn-loaded urea samples were tested for urea N release rate, leaching of water from soil, and crushing strength to assess the impact of coating on the final finished product. Pot experiments were conducted simultaneously to check the agronomic effects of Zn-coated slow-release urea on the growth and development of wheat (Triticum aestivum L.). The laboratory and pot results confirmed that the ZnO-NP treatments boost wheat growth and yield as a result of reduced N and Zn release. UZnNPs2 (urea coated with 0.5% ZnO-NPs and 5% molasses) demonstrated the best results among all the treatments in terms of slow nutrient release, N and Zn uptake, and grain yield. The UZnNPs2 treatment increased plant yield by 34% (i.e., 4,515 vs. 3,345 kg ha–1) relative to the uncoated prill-treated crop because of the slower release of Zn and N.

Only 47% nitrogen of fertilizer is taken up by a plant whereas more than 40% nitrogen of total applied fertilizer is lost to environment that causes several environmental as well as economic consequences. Slow-release fertilizers are considered as a possible large-scale solution for nitrogen loss. The present study aims to stabilize urea by coating with four different materials including calcium phosphate (CP), gypsum powder (GP), calcium nitrate (CN), and gelatin (G) individually and in combination for slow release of nitrogen to sorghum crop. The physical and chemical characteristics of coated urea were examined by FT-IR, powder XRD, SEM, and rushing strength. Results showed that coating of CP, GP, and CN over urea was uneven and rough while G coating was smooth and admirable, and no pore was observed on the surface and indicated a weak water-urea interaction. Similarly, CPG coating over urea showed a maximum crushing strength of 2.38 N/m2. Slow-release and soil leaching analysis revealed that G coated urea showed the maximum 39.12 and 779.36 ppm nutrient loss after 15- and 480-min treatment, respectively which is much better than uncoated urea (99.81 and 993.65 ppm). Results reported that the maximum plant height, diameter, and chlorophyll were observed as 132.91 ± 1.52 cm, 24.56 ± 1.00 mm, and 56.30 ± 1.03 mg/m2 with CNG coated urea. Similarly, CNG also revealed the maximum dry matter yield (DMY) of 25226.15 kg/ha in shoots and 2633.50 kg/ha in roots, nitrogen uptake (NU) of 18153.75 kg/ha in shoots and 233.99 kg/ha in roots, and apparent nitrogen recovery (ANR) of 71.14% in shoots and 4.55% in roots. It is concluded that CNG coated urea showed better DMY, NU, ANR, and pot analysis, and it is recommended as a slow-release fertilizer for large scale application to minimize nutrient loss and maximize crop production.

The rise in global population, urbanization, and desertification pushes the farming community toward intensive cropping to meet the augmented food demands with consequent exhaustion of soil’s nutritional status and fertility. In recent times, environmental pollution and cost of crop production have been enhanced due to excessive and inefficient use of nitrogenous fertilizers. As an abatement strategy, seven different coated urea fertilizers, namely, gelatin-coated (G), zinc oxide with gelatin-coated (ZnOG), zinc oxide-coated (ZnO), sonicated zinc oxide-coated (ZnO-Son), zinc oxide with molasses-coated (ZnOM), zinc sulfate with molasses-coated (ZnSM), and zinc sulfate-coated (ZnS) were prepared in a fluidized bed coater. The coated samples were characterized through XRD, SEM, and FTIR techniques, while a crushing strength test was carried out to assess the impact of inventory operations on physical integrity of coated prills. Pot tests with ryegrass (Lolium perenne) as a test crop were carried out to evaluate the effect of coated urea fertilizers on yield and nitrogen (N) and zinc uptake in order to enhance nitrogen use efficiency and reduce pollution. Our results suggest that the affinity between urea surface and coating materials was of physical nature. All zinc oxide- or gelatin-coated treatments significantly increased the dry matter yield, nitrogen uptake, apparent nitrogen recovery (ANR), zinc uptake, and apparent zinc recovery (AZnR). ZnOG was proved to be the best sample in terms of balancing soil chemical properties with improved soil nutrition and producing best with plant yield (94% higher than UC), N uptake (75% higher than UC), Zn uptake (450% higher than UC), and nitrogen use efficiency (48 vs. 23% for UC). Our results suggest that the use of such coated fertilizers can lead to improve yields, nutritional values of crops, and overall agro-ecological scenario.

The CO2 capturing is much more important not only in fuel upgrading but also for controlling global warming issues. Although much Metal-Organic Framework (MOF) based mixed matrix membranes (MMMs) exhibited great potential, the interfacial fine-tuning of inorganic MOF and organic membrane matrix was still a big obstacle. Herein, a novel bimetallic Pyrazine-functionalized MOF based polysulfone (PSf) mixed matrix membrane was prepared with adaptive interfaces via the interfacial plasticizer polyethylene glycol (PEG). The filler MOF greatly enhanced the CO2 capturing ability of pure PSf and PSf/PEG blend membranes. Structural characterizations revealed defect-free membranes. The mechanical test implied that by adding MOF in PSf, brittleness appeared and strength decreased from 2.84 to 2.26 MPa, but this strength increased up to 4.11 MPa by adding PEG. The interfacial-controlled PSf/PEG/Pyrazine-MOF membranes showed the highest CO2 permeability and solubility without loss of selectivity compared to regular MOF blended MMMs or PSf/PEG blend membranes. The permeability of CO2 significantly increased from 6.82 Barrer (for pure PSf membrane) to 17.13 Barrer (for PSf/PEG/Pyrazine-MOF membrane only adding 0.2% ultra-low-dose Pyrazine-MOF with 2% PEG). The study revealed a robust and efficient strategy to elevate gas separation performances of MMMs via the interfacial engineering.