Decrease of Pb bioavailability in solis by addition of phosphate ions

Bioavailability of Pb in contaminated soils can be highly decreased by conversion of labile Pb species into pyromorphite Pb₅(PO₄)₃Cl, induced by amendment with a phosphate source. However, PO₄ ³⁻ can be specifically adsorbed on goethite α-Fe(OH)₃ present in soils. We demonstrate that despite the stability of phosphate ions adsorbed on goethite surface, the reaction between goethite-adsorbed phosphates and aqueous lead in the presence of Cl⁻ results in crystallization of pyromorphite. Two morphological forms of pyromorphite formed on goethite were observed: 1) incrustations, indicating direct reaction of Pb and Cl ions with PO₄ ³⁻ adsorbed on goethite surface, and 2) aggregates of pyromorphite crystals indicating that the reaction with PO₄ ³⁻ ions took place in the volume of the solution. This suggests that precipitation of pyromorphite is faster than desorption of phosphates and that aqueous Pb may serve as a sink for phosphate ions by shifting the equilibrium and inducing PO₄ ³⁻ desorption.     

反相流动注射法测定海水中磷酸盐

建立了反相流动注射-结晶紫-磷钼杂多酸离子缔合体系测定海水中磷酸盐的方法,确立了最佳试验条件,有效解决了海水的盐度干扰问题.方法线性良好,检出限为0.1 μg/L,精密度和准确度均符合要求,且流路简单,操作方便,可用于现场自动分析.     

脲硫酸分解磷矿过程氟逸出规律的研究

对脲硫酸分解磷矿过程中酸解剂配比(即尿素加入量)、反应温度、磷矿粉细度、搅拌强度等对磷矿转化率和气相氟逸出率的影响进行了．探讨。实验结果表明．酸解剂配比是影响氟逸出率的最主要因素，由于尿素的加入．可使氟逸出率降低75％以上。     

Factors affecting the degradation of amoxicillin in composting toilet

The biological and non-biological factors that affect the degradation of amoxicillin in the composting process of feces have been investigated. The effect of living bacteria and the enzyme (beta-lactamase) on amoxicillin decay was examined, and our results indicated that the biological effects are likely to be negligible. Consequently, the effect of phosphate, ammonia and pH level as non-biological factors was investigated by monitoring the reduction rate of amoxicillin in phosphate and ammonia buffer solutions with several pH levels. Each reduction rate constant was integrated by a simulation model, and the each calculated amoxicillin reduction profile was compared to the reduction profiles of amoxicillin in the composting process of feces. The calculated results corresponded almost exactly to the experimental profiles. We therefore concluded that the degradation of amoxicillin in a toilet matrix was dependent on the concentration of ammonia, phosphate and hydroxyl ion.     

城市污水化学除磷的探讨

阐述了城市污水处理除磷的重要性和迫切性，而在普遍采用的生物除磷技术不能满足出水磷的排放标准时可考虑采用化学除磷技术，系统分析了化学除磷的原理，特点及影响因素，结合工程实例介绍了城市污水化学除磷的除磷效果，并指出了我国在现阶段城市的污水化学除磷技术研究与发展的目标。     

利用磷石膏生产陶瓷装饰材料

利用磷石膏为主要原材料，加入适当外加剂制成的磷石膏陶瓷材料，性能优良，抗压强度达８０ＭＰａ以上，外观色彩美丽，配方中磷石膏占６０％￣８０％。     

掺磷渣硅酸盐水泥熟料形成动力学的研究

研究了磷渣对硅酸盐水泥熟料形成动力学的影响，得到了熟料形成反应的活化能和动力学常数，研究表明，磷渣是一种较好的矿化剂。     

Fluorescence detection of phosphate in an aqueous environment by an aluminum-based metal-organic framework with amido functionalized ligands

● A novel Al-MOF was successfully synthesized by a facile solvothermal method. ● Al-MOF showed superior performance for phosphate detection. ● High selectivity and anti-interference for detection were demonstrated. ● The high coordination between Al-O and PO₄³⁻ was the key in fluorescence sensing. The on-site monitoring of phosphate is important for environmental management. Conventional phosphate detection methods are not appropriate to on-site monitoring owing to the use of complicated detection procedures, and the consequent high cost and maintenance requirements of the detection apparatus. Here, a highly sensitive fluorescence-based method for phosphate detection with a wide detection range was developed based on a luminescent aluminum-based metal-organic framework (Al-MOF). The Al-MOF was prepared by introducing amine functional groups to conventional MIL to enhance phosphate binding, and exhibited excellent fluorescence properties that originated from the ligand-to-metal charge transfer (LMCT). The detection limit was as low as 3.25 μmol/L (0.10 mg/L) and the detection range was as wide as 3–350 μmol/L (0.10–10.85 mg/L). Moreover, Al-MOF displayed specific recognition toward phosphate over most anions and metal cations, even for a high concentration of the co-existent ions. The mechanism of phosphate detection was analyzed through the characterization of the combination of Al-MOF and phosphate, and the results indicated the high affinity between Al-O and phosphate inhibited that the LMCT process and recovered the intrinsic fluorescence of NH₂-H₂BDC. The recovery of the developed detection method reached a satisfactory range of 85.1%–111.0%, and the feasibility of on-site phosphate detection was verified using a prototype sensor for tap water and lake water samples. It was demonstrated that the prepared Al-MOF is highly promising for on-site detection of phosphate in an aqueous environment.     

Jordan,minerals extraction and the resource curse

In its role as a competitive producer of phosphate and potash Jordan has not suffered noticeably from the Resource Curse over the past 50 years. However, the effects on its economy because of its geographical proximity to major oil-producing states have been both positive and negative. It is arguable that an oil resource curse has applied to Jordan.     

Facile fabrication of dolomite-doped biochar/bentonite for effective removal of phosphate from complex wastewaters

● Dolomite-doped biochar/bentonite was synthesized for phosphate removal. ● DO/BB exhibited a high phosphate adsorption capacity in complex water environments. ● PVC membrane incorporated with DO/BB can capture low concentration phosphate. ● Electrostatic interaction, complexation and precipitation are main mechanisms. The removal of phosphate from wastewater using traditional biological or precipitation methods is a huge challenge. The use of high-performance adsorbents has been shown to address this problem. In this study, a novel composite adsorbent, composed of dolomite-doped biochar and bentonite (DO/BB), was first synthesized via co-pyrolysis. The combination of initial phosphate concentration of 100 mg/L and 1.6 g/L of DO/BB exhibited a high phosphate-adsorption capacity of 62 mg/g with a removal efficiency of 99.8%. It was also stable in complex water environments with various levels of solution pH, coexisting anions, high salinity, and humic acid. With this new composite, the phosphate concentration of the actual domestic sewage decreased from 9 mg/L to less than 1 mg/L, and the total nitrogen and chemical oxygen demand also decreased effectively. Further, the cross-flow treatment using a PVC membrane loaded with DO/BB (PVC-DO/BB), decreased the phosphate concentration from 1 to 0.08 mg/L, suggesting outstanding separation of phosphate pollutants via a combination of adsorption and separation. In addition, the removal of phosphate by the PVC-DO/BB membrane using NaOH solution as an eluent was almost 90% after 5 cycles. The kinetic, isotherm and XPS analysis before and after adsorption suggested that adsorption via a combination of electrostatic interaction, complexation and precipitation contributed to the excellent separation by the as-obtained membranes.