印度某赤铁矿洗矿溢流选矿试验

为了给铁品位在50%左右的印度某赤铁矿洗矿溢流的利用提供依据,采用细筛-强磁选-阴离子反浮选流程和细筛-螺旋溜槽-强磁选-阴离子反浮选流程对该洗矿溢流进行了选矿试验。试验结果表明,在-0.076 mm占75%的磨矿细度下,两流程分别可取得精矿铁品位为67.01%,回收率为87.77%和精矿铁品位为67.12%,回收率为89.71%的选别指标。鉴于后一流程可比前一流程减少约1/3的浮选量,因此推荐采用后一流程。     

碱度和内配燃料对赤铁矿球团强度的影响

针对赤铁矿球团强度低的问题,以巴西某赤铁矿精矿为对象,研究了碱度、内配燃料以及它们的相互作用对赤铁矿球团强度的影响。结果表明：制备含镁熔剂性赤铁矿球团时,将碱度控制在0.3~1.2可显著提高预热球团和焙烧球团的抗压强度;制备内配燃料酸性含镁赤铁矿球团时,焦粉配比不超过1.0%可改善预热球团强度而基本不影响焙烧球团强度;制备内配燃料熔剂性含镁赤铁矿球团时,将焦粉配比控制1.5%以内,球团碱度控制在0.9,可显著提高焙烧球团强度。由此可见,制备内配燃料熔剂性含镁球团是改善赤铁矿球团强度的有效途径。     

磁种对赤铁矿铁矿石脱泥工艺的影响

在选择性絮凝分选过程中加入磁种，以增加絮团的磁化率，达到用磁选或磁选、重选联合方法分离絮团的目的。根据磁种在选择性絮凝－脱泥工艺分选赤铁矿中的作用试验结果，论述磁种用量、粒度对该工艺指标的影响。     

新型捕收剂对赤铁矿捕收性能的研究

介绍了新型铁矿物捕收剂ＲＣ９５０２用于浮选包钢选厂一、三系列强磁铁精矿（α４０．０３％ＳＰｃ）中的有用铁矿物试验，经一次反浮、正浮、一次精选可使精矿品位提高到６３．９１％ＳＦｅ，回收率为６７．４４％，ＦＣ９５０２能有效地捕收赤褐铁矿和磁铁矿，与用氧化石腊皂作捕收剂比较，不仅能获得更好的选别指标，而且可降低捕收剂成本约３０％．     

氟化物在硅铁分离中的应用及作用机理

包头白云鄂博矿床的选矿实践迫切地要求解决赤铁矿与含铁硅酸盐矿物分离这一难题。本文系统地考察了三类典型氟化物——氟化钠、氟氫酸及氟硅酸钠对赤铁矿和含铁硅酸盐矿物锥辉石浮游性的调整作用,讨论了分选的选择性及影响因素,成功地实现了赤铁矿和锥辉石的人工混合矿物及实际矿石的浮选分离。本文还对氟化物与矿物作用机理进行了探讨。     

铁坑褐铁矿选矿工艺研究

通过铁坑褐铁矿磨矿细度、强磁选、浮选、浮选中间产品选矿的试验,磨矿-强磁-再磨反浮选流程试验,磨矿-强磁-再磨强磁-反浮选流程试验和扩大连续选矿试验,制定了铁坑褐铁矿选矿的合理工艺流程,并确定磨矿-强磁选-再磨强磁选-反浮选工艺为选厂工业设计推荐流程,较好地解决了褐铁矿选矿工艺问题。     

不同淀粉对混合磁选精矿抑制效果的研究

通过淀粉对赤铁矿的抑制机理分析,经过浮选试验,研究了玉米淀粉、糯玉米淀粉、马铃薯淀粉、木薯淀粉在齐大山铁矿选矿分厂浮选中的作用效果。研究结果表明,各种淀粉对赤铁矿都有一定的抑制作用,各种淀粉的的分子量不相同,支链部分和直链部分的比例不同,是淀粉对赤铁矿抑制作用存在差别的主要原因。     

Controlled template-free hydrothermal synthesis of hematite nanoplatelets

Ferromagnetic α-Fe₂O₃ nanoplatelets with diameters of 100-140 nm and heights of 40-70 nm have been successfully prepared on a large-scale through double anion mediation hydrothermal method. The formation of the nanoplatelets depends on the molar ratio of hydrosulfite ions to sulfate ions. Nanoplatelets, short nanocolumns, polyhedra and a mixture of nanospheres and nanoellipsoids of α-Fe₂O₃ can be obtained by adjusting the molar ratio of HSO₃⁻ to SO₄²⁻. Compared to short nanocolumns, nanoplatelets display a smaller saturation magnetization of 7.36 emu/g and a smaller coercivity value of 485 Oe.     

Hematite nanoflakes as anode electrode materials for rechargeable lithium-ion batteries

Hematite (α-Fe₂O₃) nanoflakes and nanocubes were synthesized by liquid-solid-solution method and their properties as anode electrode materials for rechargeable Li⁺-ion batteries were measured. When changing the water to ethanol volume ratio in the synthesis system, the nanocrystals can be changed from α-Fe₂O₃ to α-FeOOH, with shapes being tuned from nanoflakes to nanocubes, non-uniform particles and nanowires. When assembled as the anode electrode materials in rechargeable Li⁺-ion batteries, the hematite nanoflakes showed one more plateau in the first discharge progress of the voltage-composition curves than hematite nanocrystals with other shapes in the literature. X-ray diffraction, high-resolution transmission electron microscope and electrochemical data showed that this extra plateau came from the formation of Li₂Fe₃O₄ nanoclusters and amorphous Li₂O. This experiment showed that like sizes, shapes of nanocrystals may also affect the detailed electrochemical progress.     

Elucidation the role of Co-MOF on hematite for boosting the photoelectrochemical performance toward water oxidation

Developing an efficient photoanode to convert solar energy into hydrogen fuel confronts big challenges owing to the sluggish water oxidation kinetics. Herein, we proposed a feasible method to coat Co-based metal-organic framework (Co-MOF) on Ti doped α-Fe₂O₃ and revealed its functions on the oxygen evolution reaction (OER) and photoelectrochemical (PEC) water oxidation. The Co-MOF/Ti–Fe₂O₃ showed a photocurrent density of 1.01 mA/cm² (1.23V_RHE) with a low turn-on voltage (V_on) of 0.80 V_RHE. The significant improvement of photocurrent density which was ca. 3 times higher than the pristine Fe₂O₃, was contributed by the improved charge separation efficiency on the surface rather than in the bulk. And this was validated by the increased trapping capacitance (C_trap) and reduced charge transport resistance (R_ct). Additionally, the low V_on was attributable to the compromise of introduced surface states and the catalytic effect of the Co-MOF. In this work, we discovered the Co-MOF not only offered catalysis sites for OER, but shed light on its influence on the overall PEC water oxidation, and led to an in-depth understanding of cocatalysts on the PEC water splitting.