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SiO2-supported BPO4 catalysts have been prepared via a convenient one-pot process, characterized by XRD, N2 adsorption/desorption, FTIR, and NH3-TPD and investigated in the production of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The results indicated that supporting BPO4 in SiO2 could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance. The effects of various reaction conditions, the effects of compositions on the catalytic activity, and the stability of the process have been studied in detail. Under the optimized conditions, an excellent 91.6% yield of salicylonitrile could be obtained, and good stability for the process was observed. The present study would provide foundation for industrial production of salicylonitrile. SiO2-supported BPO4 catalysts have been prepared via a convenient one-pot process, providing an excellent 91.6% yield of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The result indicated that supporting BPO4 in SiO2 could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance.

In the present study, thermoelectric properties of composites formed by poly (3,4-ethylenedioxy thiophene):poly (styrene-4-sulfonate) (PEDOT:PSS)/boron phosphate (BPO4) were studied. First, BPO4 was synthesized at 1000°C using boric acid and phosphoric acid as precursors. Later, PEDOT:PSS was synthesized by oxidative chemical polymerization reaction at room temperature. Their composites were prepared in different mass ratios by ultrasonic homogenization. The composites were characterized using ultraviolet–visible (UV–vis.), attenuated total reflection accessory attached Fourier transform infrared (FTIR-ATR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy/energy dispersive X-ray analyzer (SEM–EDX). The power factor of the sample was obtained using the electrical conductivity and Seebeck coefficient measurements. The positive sign of Seebeck coefficient of the pristine PEDOT:PSS turned to the negative, which is the characteristic of n-type material, by addition of BPO4. The power factor of PEDOT:PSS was increased from 0.03 μWm−1 K−2 to 252 μWm−1 K−2 for the composite containing 25% BPO4 by weight. This indicates that BPO4 can be a good additive to prepare n-type TE material.

The aim of this work was to investigate the catalysis of boron phosphate (BP) on the thermal stability and char forming in flame-retardant polyurethane–polyisocyanurate foams (FPUR–PIR) with dimethylmethylphosphonate (DMMP) and tris(2-chloropropyl) phosphate (TCPP). The flame-retardant performance and thermal stability of FPUR–PIR were evaluated by cone calorimetry (CONE), thermogravimetric analysis (TG) and microscale combustion calorimetry (MCC). Gas-phase products of FPUR–PIR during the thermal decomposition were investigated via thermogravimetric analyzer coupled with FTIR and mass spectrometry (TG–FTIR–MS). Elemental composition and content of the charred layer in detail were analyzed by X-ray photoelectron spectroscopy (XPS). It was observed that the incorporation of 3 mass% BP in FPUR–PIR decreases the heat release rate, total smoke released and CO production. Meanwhile, the addition of 3 mass% BP advances the release of gaseous products and lower the production of smoke and toxic products like –NCO compounds, PO* and cyanic acid in the gas phase. It can accelerate the dehydration of hydroxyl compounds and promote the char formation of –NCO compounds. This can improve the thermal and oxidation resistance of condensed phase. The catalytic behavior of the dehydration and char formation of BP in the thermal degradation of FPUR–PIR is attributed to Bronsted and Lewis acidic sites on BP.

Boron phosphates (BPs) with different acidities were prepared by regulating the calcination temperatures for the reaction products of boric acid and phosphoric acid. The crystal structure, morphology, surface acidity, and thermal stability were characterized by X-ray diffraction, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), chemical absorbed apparatus, and thermogravimetric analysis (TG). The effects of BPs on the combustion behavior and catalyzing the carbonization of bisphenol-A epoxy resin (EP) were investigated by the limiting oxygen index (LOI) and cone calorimetry test. Upon loading 5 mass% BP prepared at 300 °C, the LOI value of the EP/BP composites increased to 29.6%, and moreover, the peak heat release rate and average specific extinction area decreased by 43 and 25%, respectively. A possible catalyzing carbonization mechanism was explored by TG coupled with Fourier transform infrared spectroscopy (TG–FTIR), TG, FTIR, SEM, Raman spectroscopy (Raman), and XPS. The results demonstrated that BP catalyzed EP to degrade at relatively low temperature, and the yield, compactness, and graphitization degree of the char residue were obviously enhanced with an increase in the ratio of Bronsted and Lewis acid sites (B/L value) and the total surface acid sites on the BP surface. Therefore, the catalyzing carbonization flame retardancy of the EP/BP composites can be improved through regulating the surface acidity of BP.

In this study, interaction of ionic liquid (IL) and borate esters (SBs) as antiwear (AW) additives with steel surfaces in tribological contacts was examined using blends which contained no prior AW additives but all the other ingredients present in a fully formulated engine oil. In detail, low phosphorus oil blends were prepared by adding trihexyltetradecylphosphonium bis(2-ethylhexyl)phosphate (P_DEHP) at 700 ppm phosphorus and 2-methoxy-4,4,6-trimethyl-1,3,2-dioxaborinane or trimethoxyboroxine at 200 ppm boron treat rate to a partially formulated oil. The tribological properties of these novel ionic liquid (IL) additive and IL + SB additive mixtures were compared with those of zinc dialkyldithiophosphate (ZDDP) at equal phosphorus levels in the oil blends. Tribological experiments with a reciprocating cylinder on flat contact revealed that both P_DEHP and binary mixtures of P_DEHP + SB offer superior wear protection than ZDDP and the partially formulated oil without AW additives, expressed by a wear reduction of minimum 50%. X-ray absorption near edge structure spectroscopy (XANES) analysis revealed that tribologically formed films are primarily composed of calcium phosphate for oils with AW additives. The interaction of P_DEHP with SB results in additional boron oxide/boric acid and to some extent boron phosphate domains incorporated into the tribofilms.

A series of boron phosphate (BPO4) modified ion-exchanged CsX zeolites, prepared by impregnation method, were characterized by a variety of means and utilized as catalysts for the side-chain alkylation of toluene with methanol. Both BPO4 and Cs species are highly dispersed on the surface/channel of the BPO4/CsX zeolites. The addition of a small amount of BPO4 has no obvious effect on the basic strength of catalysts, but decreases the number of basic sites slightly. Meanwhile, more weak Lewis acidic sites appear with the increasing BPO4 loading. Compared with CsX, the BPO4 modified CsX catalysts exhibit lower ability for the adsorption/activation of methanol to produce surface intermediates like formaldehyde, unidentate formate and bidentate formate. Catalytic reaction results showed that modification of CsX with boron phosphate can improve both the conversion of toluene and the selectivity of styrene. The inhibition role in producing the unfavorable bidentate formate might be a key factor for finally resulting in the improvement of the catalytic properties of BPO4/CsX catalysts for the side-chain alkylation of toluene with methanol.

Boron phosphate (BPO4) is a well known catalyst for a range of organic chemical reactions. In this paper, we report the preparations and characterizations of nano-sized BPO4 and nano-BPO4-based core-shell spheres. The samples were synthesized hydrothermally using H3BO3, H3PO4 and short chain n-alkylamines (n = 3, 4) as starting materials. The resulting products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scan electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. A possible mechanism for the formation of the materials is also discussed.

The B K-edge X-ray absorption near-edge structure (XANES) spectra of two borates with tetrahedrally-coordinated B [[4]B; natural danburite (CaB2Si2O8) and synthetic boron phosphate (BPO4)] have been recorded in total electron yield (TEY) and fluorescence yield (FY) modes to investigate the surface and bulk structure of these materials. The TEY XANES measurement shows that danburite is susceptible to surface damage involving conversion of [4]B sites to [3]B sites by reaction with moisture and/or mechanical abrasion (grinding, polishing, etc.). The bulk of the mineral is essentially unaffected. Commercial boron phosphate powder exhibits more extensive surface and bulk damage, which increases with air exposure but is recovered on heating at 650°C. In contrast to ELNES, the XANES technique is not affected by beam damage and when collected in the FY mode is capable of yielding meaningful information on the coordination and intermediate-range structure of B in borate and borosilicate materials.

A novel phosphorus, nitrogen-containing compound, poly(4, 4′-diaminodiphenyl methane phenyl dichlorophosphate) (PDMPD) with high thermal stability was synthesized. The PDMPD was then incorporated into polystyrene (PS) to be used as halogen-free flame retardant. Moreover, small amounts of two boron-containing compounds, Zinc borate (ZnB) and boron phosphate (BP) were combined with PDMPD,to explore effective flame-retardant formulations for PS. The flammability and the thermal properties of the composites were evaluated using limiting oxygen index (LOI) test, microscale combustion calorimeter (MCC) and thermogravimetric analysis (TGA) respectively. A Fourier transform infrared (FTIR) spectroscopy coupled with a thermogravimetric analyzer (TG-IR) was also used to study the gas phase from the degradation of PS composites. Furthermore, the char residues of the samples were investigated by scanning electron microscopy (SEM) and FTIR. The results showed that the incorporation of PDMPD can significantly decrease the flammability of virgin PS, and enhance the thermal stability at high temperature region, in both nitrogen and air atmosphere. A combination of PDMPD with small amounts of boron compounds can further decrease the flammability.

Selective oxidation of ethane to acetaldehyde on a boron phosphate doped by magnesium or zinc oxides was considered using a semiempirical quantum chemical MINDO/3 method. Catalytic activity of boron phosphate is shown to enhance when the catalyst contains small amounts of MgO or ZnO. On the basis of calculated results a possible mechanism of this process is proposed.

A new method of molecular layering of oxides is demonstrated, typical catalysts (titanium silicate and boron phosphate formation in SiO2 surface layer) being taken as examples.

Anhydrous sol-gel condensation of triethyl phosphate [(CH3CH2O)3PO] with boron trichioride (BCl3), triethyl aluminum [(CH3CH2)3Al] or silicon tetrachloride [SiCI4] in organic solvents led to rigid gels. The pore fluid of the gels was removed under supercritical conditions in a pressurized vessel to form porous solids. The condensation chemistry prior to the gel point was monitored by solution 1H, 13C, 31P, and 11B NMR. The materials were then calcined at progressively higher temperatures to produce high surface area phosphates. Nitrogen gasphysisorption was used to determine the surface areas, total pore volume, and average pore radius of the products. FT-IR was used to determine functional groups in the materials. The microstructure was also examined by scanning electron microscopy.

IN a recent communication in Nature, Rafter1 has directed attention to the presence of appreciable proportions of boron in samples of New Zealand coal ashes.