2024, 45(5): 1-8.
doi: 10.7513/j.issn.1004-7638.2024.05.001
Abstract:
In this study, polyvinyl pyrrolidone (PVP) is used to optimize the core-shell V@C precursor structure, and the precursor is heat-treated to obtain vanadium nitride (VN) up to the National Standard VN16 grade of China. The addition of PVP promotes both the uniform dispersion of the carbon powders in the vanadium rich solution and facilitates the hydrogen bonding of ammonium polyvanadate (APV) ions, which are adsorbed on the surface of carbon powders for nucleation and growth. The as-prepared precursor by adding PVP has better encapsulated and stable carbon powder core and APV shell with uniform and moderate thickness, as well as small and homogeneous particle size distribution. In the nitridation and reduction process, the phase transition from precursor to VN is as follows: APV → V2O5 → V6O13 → V7O13 → VO2 → V3O5 → V2O3 → (VC) → VN. Due to its more stable core-shell coating structure and more uniform particle size distribution, the optimized precursor forms a more stable phase reaction interface and more active reaction sites, which reduces the reaction activation energy (Ea) at each stage, and makes it more efficient in reducing and nitriding and easier to transition to low-valent VOx and VN. In comparison with current carbothermal reduction process, the reaction time is shortened by 75%, and the flow rate of N2 is reduced from 300 mL/min to 200 mL/min, the usage of N2 is reduced by 40%, significantly reducing production costs.
In this study, polyvinyl pyrrolidone (PVP) is used to optimize the core-shell V@C precursor structure, and the precursor is heat-treated to obtain vanadium nitride (VN) up to the National Standard VN16 grade of China. The addition of PVP promotes both the uniform dispersion of the carbon powders in the vanadium rich solution and facilitates the hydrogen bonding of ammonium polyvanadate (APV) ions, which are adsorbed on the surface of carbon powders for nucleation and growth. The as-prepared precursor by adding PVP has better encapsulated and stable carbon powder core and APV shell with uniform and moderate thickness, as well as small and homogeneous particle size distribution. In the nitridation and reduction process, the phase transition from precursor to VN is as follows: APV → V2O5 → V6O13 → V7O13 → VO2 → V3O5 → V2O3 → (VC) → VN. Due to its more stable core-shell coating structure and more uniform particle size distribution, the optimized precursor forms a more stable phase reaction interface and more active reaction sites, which reduces the reaction activation energy (Ea) at each stage, and makes it more efficient in reducing and nitriding and easier to transition to low-valent VOx and VN. In comparison with current carbothermal reduction process, the reaction time is shortened by 75%, and the flow rate of N2 is reduced from 300 mL/min to 200 mL/min, the usage of N2 is reduced by 40%, significantly reducing production costs.
2024, 45(5): 49-62.
doi: 10.7513/j.issn.1004-7638.2024.05.007
Abstract:
Renewable energy-based water electrolysis is the main method of producing “green hydrogen”, but it still faces difficulties in large-scale application due to high power consumption and the resulting high cost of electricity. The way to reduce power consumption lies in the development of high-performance electrocatalysts. MXenes is a two-dimensional material composed of carbides, nitrides and carbon-nitrides with high electrical conductivity, large specific surface area, high mechanical strength and excellent hydrophilicity, which is an ideal carrier for electrocatalysts and has been widely used in the research in the field of hydrogen production by electrolysis of water. This paper firstly introduces the basic composition and structural characteristics of MXenes, summarizes and analyzes the research results on the direct use of MXenes in electrolysis of water for hydrogen production, and describes the application and progress of its use as a carrier material to anchor highly active substances for hydrogen and oxygen evolution reaction, and finally summarizes and looks forward to the future development prospects of MXenes materials.
Renewable energy-based water electrolysis is the main method of producing “green hydrogen”, but it still faces difficulties in large-scale application due to high power consumption and the resulting high cost of electricity. The way to reduce power consumption lies in the development of high-performance electrocatalysts. MXenes is a two-dimensional material composed of carbides, nitrides and carbon-nitrides with high electrical conductivity, large specific surface area, high mechanical strength and excellent hydrophilicity, which is an ideal carrier for electrocatalysts and has been widely used in the research in the field of hydrogen production by electrolysis of water. This paper firstly introduces the basic composition and structural characteristics of MXenes, summarizes and analyzes the research results on the direct use of MXenes in electrolysis of water for hydrogen production, and describes the application and progress of its use as a carrier material to anchor highly active substances for hydrogen and oxygen evolution reaction, and finally summarizes and looks forward to the future development prospects of MXenes materials.
2024, 45(5): 98-107.
doi: 10.7513/j.issn.1004-7638.2024.05.013
Abstract:
Recently, due to the increasing application of selective catalytic reduction (SCR) technology, a large number of spent SCR denitrification catalysts were inevitably produced. In order to save the resources and protect the environment, much attention should be attracted on their proper disposal. Spent SCR denitrification catalysts could be recycled as resources through the recovery of valuable components, overall utilization or solidification treatment, respectively. The valuable components could be effectively recovered from spent denitrification catalysts by acid-base leaching, active roasting, molten salt electrolysis, chemical precipitation, organic extraction, ion exchange. The catalyst could also be wholly used as a raw material for regenerating the catalyst and producing titanium-containing pellets or titanium-containing sinter. Moreover, it can also be solidified by melt solidification, cement solidification, ceramic solidification. Overall, the above-mentioned methods were comprehensively summarized and prospected, which will provide inspiration and reference for the resource utilization of spent SCR denitrification catalysts in the future.
Recently, due to the increasing application of selective catalytic reduction (SCR) technology, a large number of spent SCR denitrification catalysts were inevitably produced. In order to save the resources and protect the environment, much attention should be attracted on their proper disposal. Spent SCR denitrification catalysts could be recycled as resources through the recovery of valuable components, overall utilization or solidification treatment, respectively. The valuable components could be effectively recovered from spent denitrification catalysts by acid-base leaching, active roasting, molten salt electrolysis, chemical precipitation, organic extraction, ion exchange. The catalyst could also be wholly used as a raw material for regenerating the catalyst and producing titanium-containing pellets or titanium-containing sinter. Moreover, it can also be solidified by melt solidification, cement solidification, ceramic solidification. Overall, the above-mentioned methods were comprehensively summarized and prospected, which will provide inspiration and reference for the resource utilization of spent SCR denitrification catalysts in the future.
2024, 45(5): 130-138.
doi: 10.7513/j.issn.1004-7638.2024.05.017
Abstract:
The theoretical combustion temperature in front of the tuyere is one of the important parameters for evaluating the thermal state of the blast furnace hearth. On the basis of the traditional theoretical combustion temperature calculation model, the influence of ash content, unburned coal powder, and SiO2 gasification rate on the theoretical combustion temperature was comprehensively considered, and the theoretical combustion temperature calculation model was revised. The research results indicate that, the influence of factors ignored by traditional calculation models on the theoretical combustion temperature ranges from 53 to 55 ℃. The influence of oxygen enrichment rate, coal injection rate, blowing humidity, air temperature, coal fuel rate, coal preheating temperature, ash content, and SiO2 gasification rate on the theoretical combustion temperature decreases in sequence. The suitable theoretical combustion temperature control range for the blast furnace at Panzhihua Steel & Vanadium Co., Ltd. is2160 ~2320 ℃. And under the condition of constant blowing humidity, the suitable control range for the theoretical combustion temperature is 2220 ~2 28 0 ℃. After applying real-time online calculation of theoretical combustion temperature to the regulation of blast furnace production operations, it effectively promotes
The theoretical combustion temperature in front of the tuyere is one of the important parameters for evaluating the thermal state of the blast furnace hearth. On the basis of the traditional theoretical combustion temperature calculation model, the influence of ash content, unburned coal powder, and SiO2 gasification rate on the theoretical combustion temperature was comprehensively considered, and the theoretical combustion temperature calculation model was revised. The research results indicate that, the influence of factors ignored by traditional calculation models on the theoretical combustion temperature ranges from 53 to 55 ℃. The influence of oxygen enrichment rate, coal injection rate, blowing humidity, air temperature, coal fuel rate, coal preheating temperature, ash content, and SiO2 gasification rate on the theoretical combustion temperature decreases in sequence. The suitable theoretical combustion temperature control range for the blast furnace at Panzhihua Steel & Vanadium Co., Ltd. is
2024, 45(5): 199-204.
doi: 10.7513/j.issn.1004-7638.2024.05.027
Abstract:
In this paper the revision reasons and process evolution of new standard GB/T 2965-2023 had been briefed. And interpretation had been made on the following points such as terms and definition, product category, dimension and tolerance, heat treatment, mechanical properties, sampling and test result determination. It is hoped that this interpretation can provide guidance for production and inspection of the standard in the follow-up process.
In this paper the revision reasons and process evolution of new standard GB/T 2965-2023 had been briefed. And interpretation had been made on the following points such as terms and definition, product category, dimension and tolerance, heat treatment, mechanical properties, sampling and test result determination. It is hoped that this interpretation can provide guidance for production and inspection of the standard in the follow-up process.
2021, 42(3): 1-9.
doi: 10.7513/j.issn.1004-7638.2021.03.001
摘要：
从2020年我国钛工业钛精矿、海绵钛、钛锭、钛材等品种的产能、产量、应用和进出口等数据分析了我国钛工业的整体情况，并对目前行业存在的问题提出了建议。
从2020年我国钛工业钛精矿、海绵钛、钛锭、钛材等品种的产能、产量、应用和进出口等数据分析了我国钛工业的整体情况，并对目前行业存在的问题提出了建议。
2021, 42(2): 1-4.
doi: 10.7513/j.issn.1004-7638.2021.02.001
摘要：
总结回顾了中国钛白粉工业2019、2020年的各项行业数据和表现，分析了当前面临的形势及发展趋势，认为高质量发展成为钛白粉行业未来发展的主旋律，钛白粉产能集中度虽有提高，但洗牌效应短期内难以呈现，这也是行业发展的一个难题，另外行业监管、氯化法钛原料问题、环保及清洁生产问题仍不容忽视。
总结回顾了中国钛白粉工业2019、2020年的各项行业数据和表现，分析了当前面临的形势及发展趋势，认为高质量发展成为钛白粉行业未来发展的主旋律，钛白粉产能集中度虽有提高，但洗牌效应短期内难以呈现，这也是行业发展的一个难题，另外行业监管、氯化法钛原料问题、环保及清洁生产问题仍不容忽视。
2021, 42(5): 149-157.
doi: 10.7513/j.issn.1004-7638.2021.05.023
摘要：
简述了连铸板坯电磁搅拌技术的发展过程和现存问题，重点阐述了连铸板坯生产过程中结晶器内和二冷区电磁搅拌的工作原理和技术特点，对电磁搅拌器的安装位置进行了归纳，同时总结了板坯结晶器电磁搅拌和二冷区电磁搅拌的研究现状，探究了影响板坯电磁搅拌效果的因素及其主次关系，归纳了用于二冷区电磁搅拌支撑辊的作用及需继续探究的方向，分析了板坯电磁搅拌技术对铸坯内元素分布和等轴晶区间隙率的影响，为以后的板坯电磁搅拌研究者提供参考。
简述了连铸板坯电磁搅拌技术的发展过程和现存问题，重点阐述了连铸板坯生产过程中结晶器内和二冷区电磁搅拌的工作原理和技术特点，对电磁搅拌器的安装位置进行了归纳，同时总结了板坯结晶器电磁搅拌和二冷区电磁搅拌的研究现状，探究了影响板坯电磁搅拌效果的因素及其主次关系，归纳了用于二冷区电磁搅拌支撑辊的作用及需继续探究的方向，分析了板坯电磁搅拌技术对铸坯内元素分布和等轴晶区间隙率的影响，为以后的板坯电磁搅拌研究者提供参考。
2021, 42(3): 187-192.
doi: 10.7513/j.issn.1004-7638.2021.03.028
摘要：
在弹簧钢55SiCr成分基础上进行钒微合金化处理，获得了55SiCrV，通过淬火+回火正交试验、显微组织观察、力学性能测试和X射线衍射等手段，研究并分析了淬火+回火工艺对弹簧钢55SiCrV微观组织和力学性能的影响，结果表明：0.20%V的添加可使55SiCrV组织中存在大量弥散均匀分布的10～35 nm含钒析出相，强化效果最佳。淬火+回火处理可以改变55SiCrV的显微组织比例，其中的残余奥氏体可以降低强度和增加塑性，55SiCrV获得最佳力学性能匹配（Rm=1 815 MPa、Z=28%）的热处理工艺为900 ℃淬火+430 ℃回火，对应其残余奥氏体含量为2.3%。
在弹簧钢55SiCr成分基础上进行钒微合金化处理，获得了55SiCrV，通过淬火+回火正交试验、显微组织观察、力学性能测试和X射线衍射等手段，研究并分析了淬火+回火工艺对弹簧钢55SiCrV微观组织和力学性能的影响，结果表明：0.20%V的添加可使55SiCrV组织中存在大量弥散均匀分布的10～35 nm含钒析出相，强化效果最佳。淬火+回火处理可以改变55SiCrV的显微组织比例，其中的残余奥氏体可以降低强度和增加塑性，55SiCrV获得最佳力学性能匹配（Rm=1 815 MPa、Z=28%）的热处理工艺为900 ℃淬火+430 ℃回火，对应其残余奥氏体含量为2.3%。
2021, 42(6): 17-27.
doi: 10.7513/j.issn.1004-7638.2021.06.002
摘要：
主要介绍先进热成形技术、脉冲电流辅助成形技术和电磁辅助成形技术的特点，及其在钛合金薄壁板材成形中应用的研究进展。热成形是钛合金塑性加工应用最为普遍的成形工艺，利用高温下钛合金塑性变形软化的特征，能够实现复杂钛合金零件的成形。脉冲电流和电磁辅助成形技术目前尚未开展大规模的产业应用，其在高强度难成形材料的成形加工方面具有潜在应用前景。
主要介绍先进热成形技术、脉冲电流辅助成形技术和电磁辅助成形技术的特点，及其在钛合金薄壁板材成形中应用的研究进展。热成形是钛合金塑性加工应用最为普遍的成形工艺，利用高温下钛合金塑性变形软化的特征，能够实现复杂钛合金零件的成形。脉冲电流和电磁辅助成形技术目前尚未开展大规模的产业应用，其在高强度难成形材料的成形加工方面具有潜在应用前景。
2021, 42(5): 1-9.
doi: 10.7513/j.issn.1004-7638.2021.05.001
摘要：
从2020年全球钒资源概况，五氧化二钒、偏钒酸铵、钒铁和钒氮合金等品种的产能、产量、需求、进出口贸易和市场价格等方面阐述和分析了钒工业的整体情况，并介绍了2020年全球钒电池领域发生的主要大事件。依据目前国内外钒行业运行态势对后市进行了展望，认为全球钒扩能态势短期内不会大改，钒产品供过于求的状态将促使价格呈现盘整回归态势。“双碳”背景下的中国市场依旧是全球钒需求的主场，钒氮合金亦将成为钒产品近中期的发展趋势，钒企间的协同创新将促进钒产业逐步呈现良性“竞合”局面。
2021, 42(1): 75-82.
doi: 10.7513/j.issn.1004-7638.2021.01.013
摘要：
以煤质活性炭为原料，制备了碳酸钾（K2CO3）改性活性炭，模拟烧结烟气条件，考察了其在有SO2、CO2和O2条件下的NOx吸附效果。试验表明：0.65 mol/L K2CO3改性活性炭的NOx吸附量最高，120 ℃时NOx吸附量可达15.17 mg/g，较原样提高了20倍以上；随着吸附温度的升高，NOx饱和吸附量有所下降，稳定在13.70～13.97 mg/g；由于SO2吸附后生成稳定硫酸盐难以脱除，影响了活性炭的加热再生效果。该吸附剂适用于移动床吸附处理烧结烟气。
以煤质活性炭为原料，制备了碳酸钾（K2CO3）改性活性炭，模拟烧结烟气条件，考察了其在有SO2、CO2和O2条件下的NOx吸附效果。试验表明：0.65 mol/L K2CO3改性活性炭的NOx吸附量最高，120 ℃时NOx吸附量可达15.17 mg/g，较原样提高了20倍以上；随着吸附温度的升高，NOx饱和吸附量有所下降，稳定在13.70～13.97 mg/g；由于SO2吸附后生成稳定硫酸盐难以脱除，影响了活性炭的加热再生效果。该吸附剂适用于移动床吸附处理烧结烟气。
2021, 42(2): 179-187, 192.
doi: 10.7513/j.issn.1004-7638.2021.02.029
摘要：
为了探究Mg处理对易切削钢中夹杂物的影响，以1144高硫易切削钢为试验钢种，采用金相和能谱仪等手段研究了Mg处理对1144易切削钢中夹杂物的形态、尺寸分布和夹杂物成分的影响。结果表明：在易切削钢铸坯中，Mg处理使得易切削钢铸坯硫化物夹杂由Ⅱ类向Ⅲ类、Ⅰ类转变，分布更为均匀，同时使得复合硫化锰夹杂物比例提升。在轧材中，使得钢中夹杂物球化，并且钢中硫化锰夹杂物的尺寸和分布也得到了较好的改善，同时，Mg处理能够有效提高易切削钢的切削加工性能。
为了探究Mg处理对易切削钢中夹杂物的影响，以1144高硫易切削钢为试验钢种，采用金相和能谱仪等手段研究了Mg处理对1144易切削钢中夹杂物的形态、尺寸分布和夹杂物成分的影响。结果表明：在易切削钢铸坯中，Mg处理使得易切削钢铸坯硫化物夹杂由Ⅱ类向Ⅲ类、Ⅰ类转变，分布更为均匀，同时使得复合硫化锰夹杂物比例提升。在轧材中，使得钢中夹杂物球化，并且钢中硫化锰夹杂物的尺寸和分布也得到了较好的改善，同时，Mg处理能够有效提高易切削钢的切削加工性能。
2021, 42(6): 1-16.
doi: 10.7513/j.issn.1004-7638.2021.06.001
摘要：
β相凝固TiAl合金作为第三代TiAl基金属间化合物，凭借其突出的热变形优势，在航空航天及汽车制造等高端领域具有广阔的应用空间。然而，高温β相的引入在提高合金热变形能力的同时也使得组织演变和性能优化更为复杂。同时，受合金体系及本征脆性的影响，工业化进程相对迟缓。通过综述典型β相凝固TiAl合金的制备及加工工艺、组织与性能研究进展及工业化现状，系统分析了合金制备及加工工艺和成本优势，阐明了合金体系热变形、热处理及合金化对组织演变和性能优化的作用机制，指出合金工业化发展的限制环节及未来发展趋势。
β相凝固TiAl合金作为第三代TiAl基金属间化合物，凭借其突出的热变形优势，在航空航天及汽车制造等高端领域具有广阔的应用空间。然而，高温β相的引入在提高合金热变形能力的同时也使得组织演变和性能优化更为复杂。同时，受合金体系及本征脆性的影响，工业化进程相对迟缓。通过综述典型β相凝固TiAl合金的制备及加工工艺、组织与性能研究进展及工业化现状，系统分析了合金制备及加工工艺和成本优势，阐明了合金体系热变形、热处理及合金化对组织演变和性能优化的作用机制，指出合金工业化发展的限制环节及未来发展趋势。
2023, 44(1): 1-3.
doi: 10.7513/j.issn.1004-7638.2023.01.001
摘要：
总结梳理了2022年中国钛白粉行业的各项运行数据，如产能、产量、市场表观需求量、产能分布等，重点分析了近期钛白粉产能增长趋势及相应钛矿原料供求关系的变化。指出，2022年钛白粉产量、产能继续保持增长趋势，产能集中度进一步提高；同时，现有生产商规模的进一步扩大，业外加盟项目的增加，将导致钛矿供应的紧缺。另外，随着绿色新能源电池材料产业的兴起，大批磷酸铁或磷酸铁锂项目建设或筹建，将导致钛白粉产能激增，加剧钛矿供需矛盾，届时市场前景和行业面貌堪忧，各方应高度关注和及时调整。
总结梳理了2022年中国钛白粉行业的各项运行数据，如产能、产量、市场表观需求量、产能分布等，重点分析了近期钛白粉产能增长趋势及相应钛矿原料供求关系的变化。指出，2022年钛白粉产量、产能继续保持增长趋势，产能集中度进一步提高；同时，现有生产商规模的进一步扩大，业外加盟项目的增加，将导致钛矿供应的紧缺。另外，随着绿色新能源电池材料产业的兴起，大批磷酸铁或磷酸铁锂项目建设或筹建，将导致钛白粉产能激增，加剧钛矿供需矛盾，届时市场前景和行业面貌堪忧，各方应高度关注和及时调整。
2023, 44(3): 1-8.
doi: 10.7513/j.issn.1004-7638.2023.03.001
Abstract:
2023, 44(1): 1-3.
doi: 10.7513/j.issn.1004-7638.2023.01.001
Abstract:
