铂族金属(Platinum Group Metals,PGMs)是我国关键战略资源。其回收利用备受关注。铁捕集法作为主流火法工艺,所获Fe-PGMs合金结构致密、化学惰性强,难以破碎处理,制约后续富集与提纯。湿法工艺在处理此类合金时面临诸多挑战,如酸耗量...铂族金属(Platinum Group Metals,PGMs)是我国关键战略资源。其回收利用备受关注。铁捕集法作为主流火法工艺,所获Fe-PGMs合金结构致密、化学惰性强,难以破碎处理,制约后续富集与提纯。湿法工艺在处理此类合金时面临诸多挑战,如酸耗量大、生产成本高以及环境污染严重等。因此,如何从Fe-PGMs合金分离出PGMs成为解决问题的关键。综述了Fe-PGMs合金在富集前预处理阶段的工艺技术现状,评估了各工艺的优缺点。展开更多
This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw ma...This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw materials,incorporating CaO as an additive to fine-tune the slag's viscosity and density.By reducing FeO in the lead slag using waste graphite electrodes,pure Fe was obtained,effectively trapping the PGMs from the exhausted catalysts.The study explored the effects of reductant addition,trapping duration,slag basicity,and trapping temperature on the recovery rate of PGMs.The results indicated that a maximum recovery rate of 97.86%was achieved when the reductant was added at 1.5 times the theoretical amount,with a trapping duration of 60 minutes,a slag basicity of 0.7,and a trapping temperature of 1600℃.This research offered a greener pathway for the recovery of PGMs from spent automotive exhaust catalysts.展开更多
Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodi...Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodicity.Here,we provide both numerical and analytical evidence that a depth gradient metasurface can achieve discrete ultra-broadband perfect anomalous reflection in the microwave range in the absence of geometric periodicity.Remarkably,by adjusting the operating frequency of the incident wave,the same effect can be steadily obtained via a physically equivalent phase periodicity in the PGM.Based on this mechanism,a perfect retroreflector with a broadband response ranging from 1 GHz to 40 GHz is realized.Our work has promising applications in communication,source tracking,and military satellites.展开更多
废汽车尾气净化催化剂是铂族金属(Platinum Group Metals,PGMs)的重要二次资源之一。其资源化回收对于保障我国PGMs资源安全具有重大战略意义。综述废汽车尾气净化催化剂火法回收技术的研究现状,评价各个工艺的优缺点。火法回收技术在...废汽车尾气净化催化剂是铂族金属(Platinum Group Metals,PGMs)的重要二次资源之一。其资源化回收对于保障我国PGMs资源安全具有重大战略意义。综述废汽车尾气净化催化剂火法回收技术的研究现状,评价各个工艺的优缺点。火法回收技术在处理低品位废催化剂方面具有独特优势,但其工业化应用仍受制于高能耗、设备腐蚀等问题。未来,火法回收技术研究应着重于工艺流程的优化创新,以及低能耗和环境友好型技术的发展。展开更多
文摘铂族金属(Platinum Group Metals,PGMs)是我国关键战略资源。其回收利用备受关注。铁捕集法作为主流火法工艺,所获Fe-PGMs合金结构致密、化学惰性强,难以破碎处理,制约后续富集与提纯。湿法工艺在处理此类合金时面临诸多挑战,如酸耗量大、生产成本高以及环境污染严重等。因此,如何从Fe-PGMs合金分离出PGMs成为解决问题的关键。综述了Fe-PGMs合金在富集前预处理阶段的工艺技术现状,评估了各工艺的优缺点。
基金Funded by the Natural Science Foundation of Henan(No.252300421563)the Key Research Projects of Henan Provincial Colleges and Universities(No.25B450001)+3 种基金the Basic and Frontier Research Project of Nanyang(No.24JCQY032)National Natural Science Foundation of China(No.52201044)the Key Specialized Research&Development and Promotion Project(Scientific and Technological Project)of Henan Province(No.232102221022)the Basic and Frontier Technology Research Project of Nanyang(No.23JCQY1001)。
文摘This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw materials,incorporating CaO as an additive to fine-tune the slag's viscosity and density.By reducing FeO in the lead slag using waste graphite electrodes,pure Fe was obtained,effectively trapping the PGMs from the exhausted catalysts.The study explored the effects of reductant addition,trapping duration,slag basicity,and trapping temperature on the recovery rate of PGMs.The results indicated that a maximum recovery rate of 97.86%was achieved when the reductant was added at 1.5 times the theoretical amount,with a trapping duration of 60 minutes,a slag basicity of 0.7,and a trapping temperature of 1600℃.This research offered a greener pathway for the recovery of PGMs from spent automotive exhaust catalysts.
基金supported by the National Natural Science Foundation of China(Grant Nos.12274313,62275184,and 62411540033)Collaborative Innovation Center of Suzhou Nano Science and Technology,Suzhou Basic Research Project(Grant No.SJC2023003)+1 种基金the Gusu Leading Talent Plan for Scientific and Technological Innovation and Entrepreneurship(Grant No.ZXL2024400)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodicity.Here,we provide both numerical and analytical evidence that a depth gradient metasurface can achieve discrete ultra-broadband perfect anomalous reflection in the microwave range in the absence of geometric periodicity.Remarkably,by adjusting the operating frequency of the incident wave,the same effect can be steadily obtained via a physically equivalent phase periodicity in the PGM.Based on this mechanism,a perfect retroreflector with a broadband response ranging from 1 GHz to 40 GHz is realized.Our work has promising applications in communication,source tracking,and military satellites.
文摘废汽车尾气净化催化剂是铂族金属(Platinum Group Metals,PGMs)的重要二次资源之一。其资源化回收对于保障我国PGMs资源安全具有重大战略意义。综述废汽车尾气净化催化剂火法回收技术的研究现状,评价各个工艺的优缺点。火法回收技术在处理低品位废催化剂方面具有独特优势,但其工业化应用仍受制于高能耗、设备腐蚀等问题。未来,火法回收技术研究应着重于工艺流程的优化创新,以及低能耗和环境友好型技术的发展。
