The removal of low concentrations of rare-earth ions (e.g., Er(III)) from water has stimulated interest in the field of mineral processing and water treatment. Here, an ion-exchange and complexation-assisted precipitation method for the removal of low concentrations of Er(III) from water using heptadecyl-1,1-bisphosphonic acid (HBPA) was investigated. The results showed that effective cation-exchange between Er(III) ions and the bisphosphonate headgroup was achieved, and the solution pH abruptly decreased from 6.5 to around 3.1 at the first stage, which further led to the formation of less soluble Er(III) heptadecyl-1,1-bisphosphonate complexes. While low concentrations of Er(III) ions in water are typically treated by the addition of HBPA, followed by the addition of sodium bicarbonate (adjusting the pH to 6–8) and activate carbon, Er(III) ions could be efficiently removed from aqueous solution after about 30 min based on the cation-exchange and complexation-assisted precipitation method. Additionally, the removal of ultra trace amounts of Er(III) ions was not significantly affected by coexisting trace amounts of alkaline-earth metal ions (Mg2+, Ca2+ and Sr2+). HBPA is an effective Er(III) chelator, which may be a potential and promising alternative technique to remove Er(III) ions from aqueous solutions.

Erbium-doped hydroxyapatite (Er-HAP) particles were prepared by the co- precipitation method. The crystal structure, surface chemical composition, and fluorescent properties of Er-HAP particles were characterized by the methods of X-ray diffraction combined with Materials Studio, scanning electron microscopy-energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and fluorescence spectroscopy. The results showed that Er3+ can competitively substitute for a Ca2+ site in the crystal lattice. Under the excitation of a 340 nm light source, Er-HAP particles emitted significant fluorescence at around 419 nm (purple), 458 nm (blue), 501 nm (green), and 535 nm (green), respectively. The four corresponding luminescence bands are attributed to F-4(3/2 )-> I-4(15/2), F-4(5/2) -> I-4(15/2), F-4(7/)2 -> I-4(15/2), and S-4(3/2) -> I-4(15/2) transition states, respectively. Further, we evaluated the biomineralization ability by analyzing the formation of an interfacial layer after Er-HAP particles were immersed in simulated body fluid. When the dopant content (molar fraction) of Er3+ was 1%, it was observed that Er-HAP particles could form the mineralized layer with plate-like structures, and Er3+ incorporation affected the biomineralization ability, whereas the biomineralization rate and osieogenic performance significantly decreased with the increasing of the dopant content of Er3+. Therefore, the stronger biomineralization ability of Er-HAP particles might be exhibited while the Er dopant content was about 1%.

为提高墨鱼骨的利用价值和回收率,实验利用墨鱼骨骨粉与磷酸氢二铵在高压釜200℃条件下水热反应8 h制备羟基磷酸钙,进一步研究墨鱼骨转化羟基磷酸钙对盐酸的吸附性能,用Langmuir和Freundlich吸附等温模型拟合,结果发现采用Langmuir模型拟合相关度达0.9997,说明该吸附过程符合Langmuir吸附模型.吸附动力学实验表明,该多孔羟基磷酸钙对盐酸具有良好的吸附性能,吸附过程符合准二级动力学模型,平衡吸附量为0.2411509 mg·g-1,初始吸附速率0.2401931 mg·(g·min-1)-1.

利用墨鱼骨纹层状基质和背盾粉末为原料,利用水热法在120,150,180℃不同温度下反应8 h/24 h制备羟基磷灰石,分别利用SEM,XRD等方法分析墨鱼骨纹层状基质和背盾,以及对应的反应产物.研究表明:墨鱼骨纹层状基质和背盾的主要矿物成分为文石相碳酸钙,以及少量方解石相碳酸钙.以纹层状基质粉末为原料制备羟基磷灰石的最佳水热反应条件为:温度120℃、反应时间8 h,以背盾粉末为原料制备羟基磷灰石的最佳水热反应条件为:温度180℃、反应时间8 h.

采用复分解法,以氯化钙和碳酸钠为原料,采用SEM、XRD、FTIR、TG等方法研究二十二酸对合成碳酸钙的晶型和表面性质的影响.结果 表明,加入二十二酸之后,碳酸钙的晶体结构由方解石变成球霰石,形貌由不规则的立方状形变成了球形;碳酸钙表面全部被活化,由亲水性变成疏水性;二十二酸的羧基和Ca2+发生了化学结合反应,使碳酸钙的晶型和表面性质发生了变化.

采用硝酸钙和碳酸钠的复分解反应制备碳酸钙,通过加入肉豆蔻酸对碳酸钙的晶体结构和表面性质进行调控,采用SEM、XRD、FT-IR、TG和XPS等方法研究了添加肉豆蔻酸对碳酸钙晶体结构的影响.结果表明,加入肉豆蔻酸之后,碳酸钙的晶体结构由球霰石变成方解石,形貌由球形变成了不规则的长方体形;碳酸钙的表面全部被活化,由亲水性变成疏水性,表面疏水后,碳酸钙的团聚程度明显降低;肉豆蔻酸的羧基阴离子和钙离子发生了化学结合反应,增强了碳酸钙结构的稳定性.总之,肉豆蔻酸的加入为碳酸钙的晶型调控与表面改性提供了一条简单的思路.

The TiO2 opal shale photocatalytic composites were prepared by sol-gel method with opal shale as the carrier and tetrabutyl titanate as the titanium source.The samples have been characterized by TG-DTA,XRD and FT-IR.The photocatalytic activity of the samples was studied using degradation of methyl orange.The results showed that after acid treatment the opal shale was conducive to improve the thermal stability of the loaded TiO2,and among the acids the inhibitory effect of H2SO4 treated opal shale on the crystal change of the loaded TiO2 was more obvious,and the loaded TiO2 was not chemically bonded with opal shale,but bonded only by physical coating.After loading TiO2 on opal shale treated by different processing methods,there was obvious difference in the crystal grain size.In this experiment,the photocatalytic performance of the sample treated by H3PO4 was the best.Under UV irradiation,with the photocatalyst dosage of 0.01 g,photocatalysis time of 180 min,the removal rate of methyl orange solution with the concentration of 20 mg/L was 90％.Under visible light irradiation,with the photocatalysis time of 8h,the removal rate of methyl orange solution with the concentration of 20 mg/L was 84.6％.With increasing pH of the solution the photocatalytic activity increased,and the addition of inorganic anions was beneficial to the improvement of the photocatalytic reaction rate,but too many anions could produce a negative effect.

The photocatalysts TiO2/fly ash cenosphere composite material materials were prepared by hybrid slurry procedure with fly ash cenosphere as the carrier and tetrabutyl titanate as titanium source.The samples had been characterized by scanning electron microscope (SEM),X-ray energy-dispersive spectroscopy (EDS),X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR).The photocatalytic activity of the samples was studied through degradation of Rhodamine B.The results showed that the increase of TiO2 loading was conducive to improve the photocatalytic activity.However,too much loading maked the TiO2 fluffy in the fly ash cenosphere surface.Superfluous TiO2 were easy to fall off in the repeated use process,resulting in decrease of photocatalytic activity.The TiO2 loaded on fly ash cenosphere surface was anatase,and the load of TiO2 with fly ash cenosphere was not chemically bonded,but combined by physical adsorption.In this experiment,the optimal TiO2 loading was 28.57% (mass fraction).With the pH of the Rhodamine B solution increased,the photocatalytic activity also increased,and the degradation efficiency of Rhodamine B solution was kept above 70% even in the fifth cycle.The addition of inorganic anions was beneficial to the improvement of the photocatalytic activity,but too much anions could produce a negative effect.

Using purified diatomite as raw material and tetrabutyl titanate as precursor,the nano-TiO2/diatomite composite material was prepared by sol-gel method.The composite material was characterized by XRD、SEM、FT-IR.The photocatalytic activity of the composite materials were tested by using Rhodamine B as degradation object.The experimental results show that with the ratio of H2O/HNO3 increasing,the photocatalytic activity of composite material increases firstly and then decreases.When the ratio of H2O/HNO3 is 4,the photocatalytic acticvity of composite material is the best and the nano-TiO2 uniformly loads on the surface of the diatomite,the proportion of anatase is 85.9％,the crystal size is 14.2 nm,the degradation rate of Rhodamine B can reach 100％ in 3 h under light.

利用硅藻土结构特性和纳米二氧化钛(TiO2)优越光催化活性,以提纯硅藻土为载体,钛酸四丁酯为前驱体,采用溶胶-凝胶法制得纳米TiO2/硅藻土光催化复合材料.通过XRD、EDS、SEM、FT-IR对复合材料进行晶型结构和形貌表征分析,考察煅烧条件对复合材料光催化性能影响.实验结果表明:TiO2/硅藻土复合材料最佳煅烧温度为650℃、煅烧时间3h,此时TiO2晶型以混晶形式存在,晶粒尺寸为39.9nm;在300W高压汞灯光照3h对罗丹明B溶液降解率达到100％,经过5次重复利用后对罗丹明B降解率仍达到70.53％以上.

粒度级配是影响水煤浆成浆性的关键因素.为了提高补连塔低阶煤水煤浆成浆性,采用粗、细煤粉单独成浆和不同粒度级配煤粉成浆实验,研究粒度级配对补连塔低阶煤水煤浆的成浆性影响.说明合理的粒度级配降低了水煤浆的表观黏度,极大提高了水煤浆的稳定性和流动性.

采用水解沉淀法制备了白炭黑、硅藻土和蛋白土负载纳米二氧化钛复合材料.通过SEM和XRD等手段对复合材料分别进行了表征,并用罗丹明B溶液的光催化脱色率来评价复合材料的光催化性能.结果表明,在复合材料表面负载了大量的二氧化钛且主要以锐钛型为主,白炭黑、硅藻土、蛋白土复合材料表面负载的二氧化钛的平均粒径分别为14.6、25.7、22.9 nm.二氧化钛/白炭黑、二氧化钛/硅藻土、二氧化钛/蛋白土3种复合材料的最佳制备条件分别为:700℃煅烧2h,二氧化钛负载量为30％;700℃煅烧2h,二氧化钛负载量为20％;600℃煅烧2h,二氧化钛负载量为20％.3种复合材料对罗丹明B溶液15 min的降解率分别达到98.6％、97.4％和87.7％.

纳米二氧化钛光催化剂,由于其催化活性高、化学性质稳定、成本低、无毒等优点,已成为环境领域最有发展前景的光催化材料.针对其在催化过程中催化效率低、可见光利用率低、难回收利用等问题.本文综述了硅藻土负载纳米TiO2负载方法及TiO2掺杂改性最新研究进展,并提出了TiO2光催化剂存在问题及发展前景.

采用低温热解法(400℃～650℃)对褐煤进行改性处理,并通过红外光谱和热重对原煤热解前后物质组成进行表征,研究不同热解温度半焦的成浆性能和原煤进行配煤后的成浆性能.实验结果表明:低温热解能够有效提高褐煤的成浆性能.

综述了近年来纳米二氧化钛光催化剂共掺杂的研究进展.介绍了纳米二氧化钛光催化剂的作用机理,从促进二氧化钛可见光响应、抑制光生电子与空穴的复合、造成晶格缺陷,增加氧空位、提高二氧化钛光催化剂表面羟基含量等方面解释了纳米二氧化钛光催化剂掺杂改性的作用机理.分析比较了非金属与非金属共掺杂、非金属与金属共掺杂、金属与金属共掺杂等不同掺杂方式对二氧化钛光催化剂的催化性能影响,并对今后的研究方向提出了建议.