期刊
CHEMICAL ENGINEERING JOURNAL
卷 267, 期 -, 页码 142-152出版社
ELSEVIER SCIENCE SA
DOI: 10.1016/j.cej.2014.12.079
关键词
P(V) recovery; Hap precipitation; Batch reactor; Crystallization; CaCl2; Solid characterization
资金
- ZERODISCHARGE - Ministry of Science and Innovation (MINECO, Spain) [CTQ2011-26799]
- Catalan government [2009SGR905]
In this work, phosphorous recovery as hydroxyapatite (Ca-5(PO4)(3)OH(s) = Hap) from alkaline phosphate concentrates (0.25-1 g P-PO43-/L) using calcium chloride (6 g/L) in a batch reactor was evaluated. Ca(II) solutions was continuously fed (0.1-0.3 mL/min) up to reaching a Ca/P ratio of similar to 1.67 (5/3) to promote Hap formation. Hap powders were characterized by structural form (using X-ray diffraction (XRD), laser light scattering (LS) and Fourier transform infrared spectroscopy (FTIR)); textural form (using Field Emission Scanning Electron Microscopy with Energy Dispersive System (FE-SEM/EDS) and Brunauer-Emmett-Teller (BET)) and thermally (using Thermogravimetric Analysis (TGA)/Differential Thermal Analysis (DTA)). When pH was kept constant in alkaline values (from 8 to 11.5), Hap precipitation efficiency was improved. At pH 11.5, higher phosphorous precipitation rate was registered compared to that obtained for pH 8 and 10, but lower degree of crystallinity was observed in the Hap powders. The increase of the total initial phosphate concentration lead to the formation of Hap powders with higher degree of crystallinity and crystal diameter, but also lower mean particle size. As Ca(II) dosing rate increased Hap precipitation rate was higher, and also the mean size and degree of crystallinity of the prepared particles increased. (C) 2014 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据