Biobased Furfurylated Poplar Wood for Flame-Retardant Modification with Boric Acid and Ammonium Dihydrogen Phosphate

Furfurylated wood exhibits excellent dimensional stability and corrosion resistance,making it a promising material for constructing buildings,but it is highly flammable.Herein,flame-retardant furfurylated poplar wood was produced via a two-step process utilizing boric acid(BA)and ammonium dihydrogen phosphate(ADP)as flame-retardant components,and biomass-derived furfuryl alcohol(FA)as a modifier.The acidity of BA and ADP allowed them to catalyze the polymerization of FA,which formed a cross-linked network that immobilized BA and ADP inside the wood.The addition of BA/ADP substantially delayed the time to ignition from 10 to 385 s and reduced the total heat release and total smoke release by 58.75%and 77.31%,respectively.Analysis of the pyrolysis process showed that the decomposition products of BA and ADP protected the underlying furfurylated wood and diluted combustible gases.This method significantly improved the fire retardancy and smokeless properties of furfurylated wood,providing promising prospects for its application as an engineering material.

Molecular Dynamics Study on Configuration Energy and Radial Distribution Functions of Ammonium Dihydrogen Phosphates Solution

Molecular dynamics simulations were carried out to study the configuration energy and radial distribution functions of mmonium dihydrogen phosphate solution at different temperatures. The dihydrogen phosphate ion was treated as a seven-site model and the ammonium ion was regarded as a five-site model, while a simple-point-charge model for water molecule. An unusually local particle number density fluctuation was observed in the system at saturation temperature. It can be found that the potential energy increases slowly with the temperature from 373 K to 404 K, which indicates that the ammonium dihydrogen phosphate has partly decomposed. The radial distribution function between the hydrogen atom of ammonium cation and the oxygen atom of dihydrogen phosphate ion at three different temperatures shows obvious difference, which indicates that the average H-bond number changes obviously with the temperature. The temperature has an influence on the combination between hydrogen atoms and phosphorus atoms of dihydrogen phosphate ion and there are much more growth units at saturated solutions.

Silica supported ammonium dihydrogen phosphate(NH_4H_2PO_4/SiO_2):A mild,reusable and highly efficient heterogeneous catalyst for the synthesis of 14-aryl-14-H-dibenzo[a,j]xanthenes

catalyst for the synthesis of 14-aryl- 14-H-dibenzo[aj]xanthenes Silica supported ammonium dihydrogen phosphate （NH4H2PO4/SiO2） is found to be a recyclable heterogeneous catalyst for a rapid and efficient synthesis of various aryl-14-H-dibenzo[a,j]xanthenes with excellent yields under solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction times and milder conditions. 2009 Shahnaz Rostamizadeh. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Electrical Conduction in Deuterated Ammonium Dihydrogen Phosphate Crystals with Different Degrees of Deuteration

Conductivity measurements of deuterated ammonium dihydrogen phosphate （DADP） crystals with different deuterated degrees are described. The conductivities increase with the deuterium content, and the value of the a-direction is larger than that of the e-direction. Compared with DKDP crystals, DADP crystals have larger conductivities, which is partly due to the existence of A defects. The ac conductivity over the temperature range 25-170℃has shown a knee in the curve ofln（σT） versus T-1. The conductivity activation energy calculated by the slope of the high temperature region decreases with the deuterium content. The previously reported phase transition is not seen.

Solubility and solution thermodynamics of ammonium dihydrogen phosphate in the water–methanol system

The solubility of ammonium dihydrogen phosphate(MAP)in the water–methanol system is essential for antisolvent crystallization studies.To investigate the effect of methanol on the solubility of MAP in water,the solubility of MAP in the water–methanol system was determined by dynamic method and static equilibrium method at temperatures ranging from 293.2 to 343.2 K at atmospheric pressure.Results showed that the solubility of MAP increased with the increase of temperature and the increase of water mole fraction in the water–methanol system.The experimental solubility data were correlated with the modified Apelblat equation,the combined nearly ideal binary solvent/Redlich–Kister(CNIBS/R–K)model and the Jouyban–Acree model.The calculated results based on these three models were in very good agreement with the experimental data with the average relative deviations of 0.65%,0.97%,and 5.38%,respectively.Simultaneously,the thermodynamic properties of the MAP dissolution process in the water–methanol system,including Gibbs energy change,enthalpy,and entropy were obtained by the Van’t Hoff equation,which can be used to assess the crystallization process.

Effect of different operation conditions on PCDD/F inhibition by ammonium dihydrogen phosphate:concentrations,distributions and mechanisms

Phosphorus-containing compounds are considered as the potential alternatives of traditional inhibitors for suppressing the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs),but the suppression characteristics are scarcely studied.In this study,ammonium dihydrogen phosphate(ADP)was selected as the inhibitor to inhibit the PCDD/F formation via de novo synthesis at 350℃.The influence of oxygen content and addition method on PCDD/F inhibition was systematically investigated by means of statistical analysis and morphological characterization.The results showed that oxygen enhanced the formation of PCDD/Fs from 1470 ng g^(−1)(9.78 ng I-TEQ g^(−1))to 2110 ng g^(−1)(14.8 ng I-TEQ g^(−1)).ADP significantly inhibited the PCDD/F formation,with inhibition efficiencies ranging from 82.0%to 97.7%.Herein,a higher oxygen content and the premixed way intensified the suppression effect.Dibenzo-p-dioxin(DD)/dibenzofuran(DF)chlorination was proven to be effectively suppressed while chlorophenol(CP)route was not obviously influenced.With the addition of ADP,Cl source was significantly reduced and the formation of organic Cl was effectively inhibited.Also,it decreased the proportion of C–O/C=N and C=O,revealing the efficient inhibition of carbon oxidation.Meanwhile,the formation of copper phosphate and copper pyrophosphate was observed in XPS(X-ray photoelectron spectroscopy)spectra,indicating that the catalytic metal Cu was chelated and passivated by ADP.The premixed way had a better effect on reducing Cl resources,inhibiting oxidation and chelating metals,due to the direct contact with inhibitor.However,the separation method could only depend on the decomposed gases,resulting in a lower inhibition efficiency.

基于磷酸二氢铵-氯化钾的新型氮磷钾水溶肥制备工艺及氯含量调控研究

农业绿色高质量发展对农业肥料的品质提出了更高要求,其中新型水溶肥的开发受到了极大关注。本文以磷酸二氢铵和工业氯化钾为原料,通过复分解工艺,制备了新型氮磷钾水溶肥,采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、扫描电镜(SEM)等手段,考察了原料质量比、原料添加量、反应温度以及搅拌速度等因素对氮磷钾水溶肥中的氯含量及产率的影响。结果表明:原料质量比对氮磷钾水溶肥的制备具有决定性影响;在原料质量比为1∶1、NH_(4)H_(2)PO_(4)和KCl添加量均为20 g、反应温度为80℃、搅拌速度为500 r/min时制备的氮磷钾水溶肥中氯含量最低,产率最高,产物组分主要是K_(0.37)(NH_(4))_(0.63)H_(2)PO_(4)。研究成果可为我国高效、环保新型肥料的研发提供参考。

磷酸二氢铵对甲烷爆炸火焰结构影响的抑爆试验研究

本研究旨在探讨磷酸二氢铵对甲烷/空气爆炸火焰传播和结构的直观影响。基于能量守恒和化学动力学原理,在60L定容燃烧弹中进行甲烷抑爆试验,利用纹影技术获取爆炸火焰传播图像并进行分析。试验结果表明,磷酸二氢铵对爆炸火焰有减弱作用,并且随着其浓度增加,火焰传播速度下降显著,火焰半径缩小,在接近最佳甲烷气体爆炸浓度时,效果更加明显。其中,150 g/m 3磷酸二氢铵抑制9.5%、8.0%浓度甲烷爆炸体现出高效性。此外,磷酸二氢铵使甲烷爆炸反应时间延长,表现为流场中自发光时间的显著增加。从热力学角度来看,磷酸二氢铵的分解吸热效应降低了火焰温度,不仅减缓火焰传播速度,也导致火焰边界呈现出片状和变薄的特征。这种现象在甲烷浓度为11%时表现得尤为突出,进一步证实了磷酸二氢铵作为抑爆添加剂的潜在效能。

喷尘压力对磷酸二氢铵分散状况及抑制甲烷爆炸影响实验研究

本研究旨在探究不同喷尘压力下喷射磷酸二氢铵对其分散状况及抑制9.5%甲烷爆炸特性的影响。通过在60 L定容燃烧弹中进行实验,将高速摄像和压力传感器采集到的数据进行处理并结合热力学和空气动力学进行分析,发现喷尘压力通过影响分散状况对磷酸二氢铵的抑爆效果产生显著影响。实验结果表明,在1.2 MPa的喷尘压力下,3 g和6 g磷酸二氢铵的分散效果不佳。9 g磷酸二氢铵在各种喷尘压力条件下均能实现较为均匀的分散,尤其在0.8 MPa喷尘压力下表现最为显著。在较高的喷尘压力下,磷酸二氢铵对爆炸初始发展的抑制效果有所减弱。0.8 MPa的适中喷尘压力条件下,磷酸二氢铵展现出了优异的分散及抑爆效果。这些发现为理解喷尘压力对磷酸二氢铵抑制甲烷爆炸效果的影响提供了重要的实验依据,并对制定有效的矿井防爆措施具有重要的指导意义。

硫氧镁水泥基蔗渣板的制备工艺及抗泛霜性探究

以未经任何处理的蔗渣为原料,硫氧镁水泥为胶黏剂,通过一步成型法制备硫氧镁水泥基蔗渣板,并探究氧硫比(活性氧化镁和七水硫酸镁的物质的量比)、胶料比(硫氧镁水泥和蔗渣的质量比)、热压温度、原料含水率及外加剂种类(乳化石蜡、氢氧化铝和磷酸二氢铵)对蔗渣板性能的影响。结果表明:在氧硫比为5,胶料比为3∶7,原料含水率为20%,热压温度为80℃的条件下,制备硫氧镁水泥基蔗渣板的密度为0.86 g/cm^(3),静曲强度为16 MPa,弹性模量为1980 MPa,内结合强度为0.4 MPa,2 h吸水厚度膨胀率为4.6%,满足GB/T 39032—2020《难燃刨花板》中难燃P2型刨花板(干燥状态下使用的难燃家具型刨花板)的物理力学性能要求,甲醛释放量分级满足GB/T 39600—2021《人造板及其制品甲醛释放量分级》中ENF级要求,燃烧性能达到GB 8624—2012《建筑材料及制品燃烧性能分级》中B1(B)级阻燃等级。外加剂磷酸二氢铵的加入有效提高了硫氧镁水泥基蔗渣板表面的抗泛霜性能。

磷酸二氢铵-尿素缩聚生产全水溶聚磷酸铵的工艺研究及水溶肥展望

以磷酸二氢铵和尿素为原料,介绍了缩聚法全水溶聚磷酸铵的生产方法。

磷酸二氢铵与硅烷偶联剂在纺织浆料中的应用与研究

利用INSTRON万能强力仪、傅里叶红外光谱仪、X射线衍射仪等仪器,探讨磷酸二氢铵加入由磷酸酯淀粉与丙烯酸酯组成的共混浆料的时机,研究磷酸二氢铵和硅烷偶联剂KH580处理的共混浆料,所形成浆膜的成分和结晶度,以及对织物的上浆率。研究结果表明:磷酸二氢铵在共混浆料糊化前加入,对共混浆料性能的提升效果更好。磷酸二氢铵会降低浆膜的结晶度,改善浆料的渗透性能,增加浆膜的强力。硅烷偶联剂对浆膜强力影响较小。两者共同作用时对浆膜性能有增强作用。改变硅烷偶联剂的加入量对上浆率的影响不明显,但增加磷酸二氢铵的加入量,织物上浆率增加。

叶面喷施磷酸二氢钾铵对猕猴桃果实发育和品质的影响研究

为促进猕猴桃果实发育,提高果实品质,以中华绿肉猕猴桃为试验品种,叶面喷施0.5%磷酸二氢钾铵,研究喷施叶面肥磷酸二氢钾铵对猕猴桃果实发育和品质的影响。结果表明,喷施叶面肥磷酸二氢钾铵可促进果实果梗长度、粗度以及果实横径、纵径的发育;显著提高猕猴桃果实中维生素C含量,但对猕猴桃果实重量、可溶性固形物含量及可滴定酸含量无显著影响。

蒙脱土协同阻燃剂涂覆纸张的制备及其性能

针对纸张易燃的问题,基于钠基蒙脱土的吸水膨胀及钠离子交换特性,分别用钠基蒙脱土吸附尿素(UM)、磷酸二氢铵(ADP)和三聚氰胺(MEL)制成新型复合阻燃剂,并涂覆于纸张表面制备阻燃纸张。通过傅里叶变换红外光谱(FTIR)、热重分析(TGA)、垂直燃烧测试、力学性能测试等对阻燃纸张的微观结构、阻燃性能和力学性能进行分析。结果表明,相比于空白纸张,利用MMT-UM、MMT-ADP和MMT-MEL涂覆得到的阻燃纸张,其阻燃性能得到显著提升,热稳定性得到增强。且随阻燃剂用量的增加,制备的阻燃纸张的炭化长度明显变短,断后伸长率、撕裂强度和挺度等力学性能都有不同程度的提升。

硝磷酸氨法净化生产磷酸二氢铵工艺研究

针对硫酸法湿法磷酸生产磷酸二氢铵副产磷石膏的问题,基于硝酸法冷冻母液深度脱硝后的净化液,采用氨中和工艺生产工业级磷酸二氢铵,系统研究了反应温度、磷酸浓度、反应时间、搅拌速率、pH、杂质离子浓度等因素对于氨中和工艺的影响。结果表明,氨中和过程中杂质离子生成磷酸盐沉淀影响磷收率,且杂质离子之间主要以形成复盐沉淀互相影响。通过对比氨中和后滤液的成分可得出最佳工艺条件:P_(2)O_(5)质量分数为15%、反应温度为85℃、搅拌速率为250r/min、反应时间为40min、pH为4.3,最后以最佳工艺条件制备的磷酸二氢铵产品达到一级产品标准要求。

脱脂大豆蛋白/蔗糖-磷酸二氢铵胶黏剂的合成工艺研究

以脱脂大豆蛋白(defattedsoyprotein,DSF)、蔗糖(Sucrose)、磷酸二氢铵(ammonium dihydrogen phosphate,ADP)为主要原料,制备一种新型大豆蛋白-蔗糖基胶黏剂(DSF/SADP),探讨固体物质质量分数、脱脂大豆蛋白与蔗糖-磷酸二氢铵糖液的质量比、合成温度及合成时间对胶黏剂胶合强度的影响,分析胶黏剂的热固化行为与固化机理。在胶黏剂的优化合成工艺:固体物质质量分数70%、脱脂大豆蛋白与蔗糖-磷酸二氢铵溶液质量比1∶4、合成温度70℃、合成时间3h的条件下,热压温度为170℃,热压时间为7min时,制备三层胶合板的湿胶合强度为0.99MPa。胶黏剂不溶解率、热重分析和差示扫描量热分析的结果显示,DSF/SADP胶黏剂在热降解过程中可能伴随着缩聚反应的发生;红外光谱测试和微观形貌观察结果显示,5-羟甲基糠醛或其衍生物参与交联反应,形成的C-O-C是固化后聚合物的主要连接键;加入DSF的胶黏剂固化后表面孔洞直径减小,表面更加致密。

湿法磷酸生产电池用磷酸二氢铵的工艺探索

基于湿法磷酸生产工业级MAP的生产装置,使用流程模拟软件进行了分析论证,通过部分工艺改造,可以升级产品质量,基本达到电池用磷酸二氢铵的要求,并在生产线上得到了验证。

磷酸二氢铵阻燃PTMG/TDI体系聚氨酯弹性体制备及性能研究

将磷酸二氢铵(ADP)作为阻燃剂,以聚四氢呋喃醚(PTMG)、甲苯二异氰酸酯(TDI)、4,4'-亚甲基二(2-氯苯胺)(MOCA)为主要原料,通过预聚体法合成了阻燃剂含量不同的聚氨酯弹性体。讨论了ADP含量对PTMG/TDI体系聚氨酯弹性体的阻燃性及力学性能的影响。结果表明:ADP对聚氨酯弹性体的力学性能影响较大,随着ADP用量的增多,拉伸强度、断裂伸长率、撕裂强度以及耐磨性能下降;聚氨酯弹性体的阻燃性能提高,氧指数(LOI)随着ADP含量的增多而增大,阻燃等级从UL-94 V-2级达到V-0级。

腐殖酸和含磷物质对模拟铅污染农田土壤的钝化效应

利用磷酸二氢铵、过磷酸钙、羟基磷灰石与腐殖酸单独以及复配施用对模拟铅(Pb)污染农田土壤进行钝化处理,采用乙二胺四乙酸二钠盐(EDTA)浸提法、生物可利用性提取(physiologically based extraction test,PBET)评价Pb污染土壤的钝化效果,并通过BCR形态分级实验研究钝化前后土壤Pb形态的变化,探讨不同钝化剂的修复机理.结果表明,施用不同的钝化剂均能降低土壤EDTA和PBET提取态Pb的质量分数,腐殖酸与磷酸盐复配施用的效果优于单一钝化剂处理,腐殖酸与羟基磷灰石(P/Pb物质的量比为2.4)复配施用时效果最明显,土壤EDTA和PBET提取态Pb的质量分数分别降低了29.7%、18.1%;BCR形态分级实验表明,添加钝化剂可有效减少土壤活性较高的弱酸提取态Pb的含量,增加活性较低的残渣态Pb含量,与单一钝化剂处理相比,腐殖酸和磷酸盐复配施用效果更好,尤其是与难溶性的羟基磷灰石复配施用效果最显著.

含磷酸二氢铵细水雾灭火有效性研究

采用小尺度灭火实验,在标准受限空间下研究磷酸二氢铵添加剂不同添加量对细水雾扑灭汽油池火的有效性,分析磷酸二氢铵的加入细水雾灭火机理的不同。受限空间尺寸3 m×3 m×3 m,油盘直径33 cm,工作压力2 MPa。结果表明:加入磷酸二氢铵后,火焰温度明显降低,且大大缩短了细水雾的灭火时间;随着磷酸二氢铵浓度的不断增大,细水雾的灭火时间先减小后增大,存在一个最短的灭火时间。