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In this study, zinc borate hydrate (Zn3B6O12 · 3.5H2O) was synthesized from zinc oxide (ZnO) and boric acid (H3BO3) via a novel method of ultrasonic irradiation. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and Raman spectroscopy were used to characterize the synthesized products. Scanning electron microscopy (SEM) was used to determine the effects of reaction time and reaction temperature on the morphology of the products. Thermal dehydration kinetics were studied using thermal gravimetry and differential thermal gravimetry analysis (TG/DTA). The Doyle and Kissinger non-isothermal kinetic methods were used to analyse the TG/DTA data. The XRD results confirmed the successful synthesis of Zn3B6O12 · 3.5H2O at a range of reaction temperatures and times. Additionally, FT-IR and Raman analysis of the products identified peaks specific to zinc borate. Using the methods of Doyle and Kissinger, the activation energies of thermal dehydration of zinc borate were found to be 341.61 kJ/mol and 390.17 kJ/mol, respectively.

Zinc borate hydrate (Zn3B6O12·3.5H2O) was synthesized from zinc sulfate heptahydrate (ZnSO4·7H2O), anhydrous zinc chloride (ZnCl2), and boric acid (H3BO3). The product was characterized by X-ray diffraction, Fourier-transform infrared and Raman spectroscopy, and thermal gravimetry and differential thermal gravimetry. The effects of reaction time and temperature on product morphology were studied by use of scanning electron microscopy. Results from thermal analysis showed that dehydration occurred in two steps. Thermal dehydration kinetics were investigated by use of the Coats–Redfern and Horowitz–Metzger non-isothermal kinetic methods. In the Coats–Redfern method, activation energies were found to be 225.40 and 570.63 kJ/mol for the first and second steps, respectively. In the Horowitz–Metzger method, activation energies were found to be 254.33 kJ/mol for the first step and 518.22 kJ/mol for the second step.

Zinc borate (ZB) was synthesized using zinc oxide, boric acid synthesized from colemanite, and reference ZB as seed. The effects of reaction parameters such as reaction time, reactant ratio, and seed ratio on its yield were examined. Then, the effects of palm oil with solvents (isopropyl alcohol (IPA), ethanol, and methanol) added to the reaction on its hydrophobicity were explored. Reactions were carried out under determined reaction conditions with magnetically and mechanically stirred systems. The produced ZB was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and measurements of contact angle identified hydrophobicity. The results showed that hydrophobic ZB was successfully produced under determined reaction conditions. The change of process parameters influenced its yield and the usage of palm oil provided hydrophobicity.

The aim of this study was to synthesize zinc borate using zinc oxide, reference boric acid, and reference zinc borate (reference ZB) as the seed, and to investigate the effects of modifying agents and reaction parameters on the hydrophobicity and yield, respectively. The reaction parameters include reaction time (1–5 h), reactant ratio (H3BO3/ZnO by mass: 2–5), seed ratio (seed crystal/(H3BO3+ZnO) by mass: 0–2wt%), reaction temperature (50–120°C), cooling temperature (10–80°C), and stirring rate (400–700 r/min); the modifying agents involve propylene glycol (PG, 0–6wt%), kerosene (1wt%–6wt%), and oleic acid (OA, 1wt%–6wt%) with solvents (isopropyl alcohol (IPA), ethanol, and methanol). The results of reaction yield obtained from either magnetically or mechanically stirred systems were compared. Zinc borate produced was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and contact angle tests to identify the hydrophobicity. In conclusion, zinc borate is synthesized successfully under the optimized reaction conditions, and the different modifying agents with various solvents affect the hydrophobicity of zinc borate.

Magnesium borate (MB) is a technical ceramic exhibiting high heat resistance, corrosion resistance, great mechanical strength, great insulation properties, lightweightness, high strength, and a high coefficient of elasticity. Zinc borate (ZB) can be used as a multifunctional synergistic additive in addition to flame retardant additives in polymers. In this study, the raw materials of zinc oxide (ZnO), magnesium oxide (MgO), and boric acid (H3BO3) were used in the mole ratio of 1 : 1 : 9, which was obtained from preexperiments. Using the starting materials, hydrothermal synthesis was applied, and characterisation of the products was performed using X-Ray diffraction (XRD) and Fourier transform infrared (FT-IR) and Raman spectroscopies. The forms of Zn3B6O12·3.5H2O, MgO(B2O3)3·7(H2O), and Mg2(B6O7(OH)6)2·9(H2O) were synthesised successfully. Moreover, the surface morphology was investigated using scanning electron microscopy (SEM), and the B2O3content was determined. In addition, the reaction yields were calculated. The results of the B2O3content analysis were in compliance with the literature values. Examination of the SEM images indicated that the obtained nanoscale minerals had a reaction efficiency ranging between 63–74% for MB and 87–98% for ZB. Finally, the fire-retarding properties of the synthesised pure MBs, pure ZBs, and mixtures of MB and ZB were determined using differential thermal analysis and thermal gravimetry (DTA-TG) and differential scanning calorimetry (DSC).

In this study, zinc borate (ZB) was synthesized by reacting zinc oxide and boric acid in the presence of standard ZB (w/w, in terms of boric acid) in order to promote crystallization. The effects of seed, H3BO3/ZnO (boric acid/zinc oxide) ratio, reaction time, water volume, reaction temperature and cooling temperature on yield were investigated for pilot-scale equipment. The results indicated that the addition of seed (w/w) to a saturated solution of reactants increased the yield of the reaction. The results of reaction yields obtained from either magnetically or mechanically stirred systems were compared. At various reaction times, the optimal yield was 86.78 % in a saturated aqueous solution. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Thermogravimetric / Differential Thermal Analysis (TG/DTA). The results displayed that ZB was successfully produced under the optimized reaction conditions and the product synthesized had high thermal stability.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4432

In general, zinc oxide and boric acid are used to produce zinc borate. In this study, zinc carbonate was used instead of zinc oxide as the novel zinc source. The purpose of this study was to synthesize hydrophobic, nanostructured zinc borate (3ZnO·3B2O3·3.5H2O) by reaction of zinc carbonate, instead of zinc oxide, with boric acid reference material, and with zinc borate reference material as seed. The modifying agents propylene glycol, kerosene, and oleic acid were used to produce hydrophobic zinc borate. Different solvents (isopropyl alcohol, ethanol, and methanol) were used to obtain a homogeneous phase. The effects of different modifying agents and solvents on the hydrophobicity and nanostructure of the product were investigated. The synthesized zinc borate was characterized by X-ray diffraction and Fourier-transform infrared spectroscopy. Contact angles were measured to determine the hydrophobicity of the products and scanning electron microscopy was used to study both the morphology and nanostructure of the products. Hydrophobic, nanostructured zinc borate was successfully produced by use of zinc carbonate instead of zinc oxide as the novel zinc source. Use of different modifying agents and solvents affected both hydrophobicity and nanostructure.