Beijing University of Technology

Yufeng Wu

Dean Pan

Jian Li

Tieyong Zuo

Xiaomin Liu

Qijun Zhang

Haoran Yuan

Liquan Li

Jiewen Yan

Gongqi Liu

De'an Pan

Xudong Sun

Minwei Song

A ceramic-based composite material used for low-concentration formaldehyde degradation, and preparation method therefor belonging to the technical field of environmental engineering. The present invention comprises: utilizing an alkali metal-transition metal (i.e. A-T) alcohol solution mixed at low temperature with a TiOsol to obtain an A-T-TiOsol; immersing activated ceramic (HFC) into the A-T-TiOsol, and stirring at normal temperature to obtain A-T-TiO/HFC; subjecting the obtained A-T-TiO/HFC to primary drying and primary low-temperature calcination to form A-T-TiO/FC; then immersing the A-T-TiO/FC into a metal-organic framework (MOF)-amino silane sol to obtain an aminated A-T-TiO/MOF/NFC precursor; and finally, subjecting the obtained precursor to secondary drying and secondary low-temperature calcination, forming an A-T-TiO/MOF/NFC composite material. The present invention effectively degrades low-concentration formaldehyde in indoor environments or in air. Loading MOF on an aminated ceramic and doping alkali metal significantly improve the formaldehyde enrichment and degradation performance of the composite material, which is beneficial to the thorough removal of low-concentration formaldehyde in indoor environments or in air.

Ceramic-based composite material used for low-concentration formaldehyde degradation and preparation method therefor

A green resource-based method of thermal mass synergy in waste Integrated circuit board mainly includes carbonization cracking system, crushing and separation system, gasification cracking system and heat value utilization and comprehensive recovery system. Compared with existing techniques, carbonization cracking system can realize the dry distillation cracking of organic matter in waste integrated circuit board which converts carbon, hydrogen and other elements into fuel carbonized cracking gas and cracking oil, the heat from the combustion of the carbonization cracking gas of the invention provides the energy needed for the carbonization cracking to realize self-heating carbonization cracking. Carbonization cracking products are cracked and separated to solve the problems such as hard to break and organic coating metal caused by direct crushing and separation of traditional circuit boards which Improves crushing and separation effect; gasification cracking system achieves the comprehensive utilization of carbon, the gasified cracking gas can be used as a heat source for subsequent valuable metal recovery to further improve the utilization rate of calorific value. The invention has the characteristics of: high heat value utilization rate, low energy consumption, high metal recovery rate, short process recovery of valuable metal and no pollution of flue gas.

Green resource-generating method based on thermal mass synergy of waste integrated circuit board

The invention discloses a method for preparing lead smelting slag glass-ceramics based on the oxidation of silicon-rich silicon smelting slag and composition adjustment, and belongs to the technical field of resource utilization of smelting slag rich in monatomic silicon. The method comprises the steps: mixing the silicon slag rich in monatomic silicon with an oxidant, a fluxing agent and a clarifying agent according to a formula ratio, ball-milling and screening to obtain a tempering raw material with uniform size, and performing high-temperature oxidation melting on the tempering raw material to form an oxidation-state molten tempering material; and carrying out further mixed melting on the molten tempering material and hot lead slag, carrying out water quenching to obtain basic glass, and carrying out heat treatment system on the obtained basic glass to form the glass ceramics. According to the method, the smelting slag rich in monatomic silicon is subjected to oxidation tempering and mixed melting with the hot lead slag to prepare the basic glass, and the glass ceramics are obtained by regulating and controlling the heat treatment system of the basic glass. The method is simple in technological process, high in production efficiency and low in cost, achieves the collaborative high-value conversion target of the silicon-rich silicon slag and the lead slag, and is easy to industrially popularize and apply.

Method for preparing lead smelting slag glass-ceramics based on the oxidation of silicon-rich silicon smelting slag and composition adjustment

The invention relates to the field of efficient separation and recovery of bromine by full wet method, especially to a two-step separating method of bromide and recovery of lead and zinc from printed circuit board Incineration ash. It mainly includes first sodium hydroxide alkaline leaching, secondary sodium peroxide alkaline leaching, pH adjustment, separate lead and zinc, bromide evaporation and crystallization to recover crude bromide and other steps. Compared with traditional comprehensive recovery process of ash, the invention uses sodium hydroxide to dissolve bromide, lead and zinc, and uses the strong oxidation of sodium peroxide in alkaline environment, copper bromide and other bromine are oxidized and leached; through two-step method, the efficient leaching of bromine, lead and zinc is realized, silver and other precious metals are enriched at the same time. It is beneficial to subsequent recovery of precious metals and has the characteristics of short tail liquid discharge.

Method of separating and recovering bromine from printed circuit board incineration ash by two-step process

The invention relates to a method of separating and extracting rare-earths from rare-earth polishing powder waste and regenerating rare-earth polishing powder, which is characterized by: firstly, process the waste powder with first acid leaching, alkali roasting, and second acid leaching to separate and extract rare-earths from rare-earth polishing powder waste to obtain the leaching solution of rare-earth chloride; secondly, precipitate from the leaching solution with ammonia to remove impurities and hydrochloric acid solution to obtain the purified solution of rare-earth chloride; thirdly, co-precipitate from the solution acquired in the second step with hydrofluoric acid, ammonium bicarbonate, and dispersant to obtain the lanthanum cerium fluoro-carbonate; and finally, after drying, two-stage high-temperature calcination, and ball milling, the regenerated rare-earth polishing powder with decent polishing performance can be obtained. The total leaching efficiency of rare-earths in the rare-earth polishing powder waste of the present invention reaches more than 95%, and the total recovery efficiency of rare-earths reaches more than 93%, which realizes the efficient separation, extraction, and regeneration of rare-earths in the rare-earth polishing powder waste.

Method for separating and extracting rare-earth and regenerating rare-earth polishing powder from rare-earth polishing powder waste

The invention discloses a method for synergistically preparing ferrosilicon alloy and glass-ceramics from photovoltaic waste slag and non-ferrous metal smelting iron slag, and belongs to the technical field of collaborative resource utilization of various smelting slag areas. According to the method, the zinc rotary kiln slag and a reduction tempering agent are subjected to batching, mixing and high-temperature melting to form a reduction-state iron-containing material. The iron-containing material and the silicon slag are further subjected to mixed melting, water quenching and sorting to obtain the ferrosilicon alloy and residual waste slag. The residual waste slag is subjected to tempering, melting, molding, annealing and heat treatment to obtain the glass ceramics. According to the method, the ferrosilicon alloy and the glass ceramics are prepared from the silicon slag and the zinc rotary kiln slag, and a collaborative resource utilization target of the regional smelting slag is achieved. The ferrosilicon alloy is obtained through high-temperature reduction of the zinc rotary kiln slag and chemical combination of the zinc rotary kiln slag and the silicon-rich silicon slag. Because the high-temperature decomposition of silica is not involved, the process greatly reduces the energy consumption, saves the cost and is suitable for industrial popularization and application.

Method for synergistically preparing Ferrosilicon alloy and glass-ceramics from photovoltaic waste slag and non-ferrous metal smelting iron slag

The invention discloses a method for cracking slag and smelting soot of the waste circuit board, belongs to the field of comprehensive recycling of valuable elements from typical soot of waste circuit boards, and particularly relates to a method for cracking slag and smelting soot of the waste circuit board for debromination and comprehensive recovery of copper and zinc. The method includes the following steps of: crushing and sorting, mixture roasting, reinforced leaching, replacement and silver precipitation, sulfuration and copper precipitation, and evaporation crystallization. Compared to traditional recycling technology, the purpose of treating two kinds of solid waste in a coupling mode through one recycling technology is achieved. Through mixed sulfuric acid roasting, the requirement of bromide synergistic removal of the waste circuit board cracking slag and smelting soot is met, and the purpose of selective conversion of copper and zinc is achieved.

Method for disposal of waste printed circuit board thermal cracking slag and smelting soot

The invention discloses a method for producing silicon carbide from waste circuit board cracking residue, belongs to the field of comprehensive utilization of waste circuit board cracking products, and particularly relates to a method for high-valued utilization of non-metal components in waste circuit board cracking residue. The method mainly comprises the following steps: rolling and crushing, vibration sorting, ultrafine pulverization and electro-separation, quantitative batching, microwave sintering and discharging and grading. Compared with the prior art, rolling crushing is adopted to replace traditional shearing crushing, microwave sintering is adopted to replace a traditional Acheson smelting furnace, the effects of being easy to operate, saving energy and reducing consumption are achieved, the production efficiency is greatly improved, and the production cost is reduced. A brand-new method for obtaining high-purity silicon carbide by partially replacing anthracite and quartz sand with cracked coke and silicon dioxide in waste circuit board light plates or epoxy resin cracking residues is adopted, and high-value utilization of waste resources is achieved. The method has the characteristics of simple and feasible process, low manufacturing cost and wide adaptability, and is beneficial to improving the economic benefit and social benefit of enterprise production.

Method for producing silicon carbide from waste circuit board cracking residue

The invention discloses Method for whole component microwave fast digestion and precious metal extraction from ionic liquid of waste circuit board, and belongs to the field of hydrometallurgy. Based on the theory that microwaves can directly penetrate through a leaching medium to directly heat a circuit board, microwave-assisted leaching can reinforce mass transfer and heat transfer in the traditional leaching process, the leaching time is greatly shortened, and the leaching efficiency is improved. Before leaching, a waste circuit board does not need to be smashed, and environmental protection is achieved while energy is saved. The temperature rising process and reaction time of the reaction can be controlled, the whole process is conducted under the airtight condition, heat loss in the leaching process is avoided, the valuable leaching rate is high, the selectivity is high, and efficient leaching of valuable metal can be achieved. Precious metal leachate is extracted through imidazolium ionic liquid, the selectivity of the imidazolium ionic liquid to gold is high, and the co-extraction phenomenon of gold, nickel, copper and other ions is avoided. The method for extracting the precious metal leachate through ionic liquid is a green and clean recycling method, and the overall recycling rate of gold, nickel and copper can reach 99% or above.

Method for whole component microwave fast digestion and precious metal extraction from ionic liquid of waste circuit board

The invention relates to a method for multi-metal products recovery from pyrolytic waste integrated circuit boards. The method mainly comprises the steps of smelting and blending, atomization, acidolysis and filtration, noble metal recycling, copper extraction and back extraction, nickel extraction and back extraction. Compared with the prior art, the method has the advantages that smoke pollution and the smelting slag treatment in the process of preparing a black copper ingot through multi-metal collaborative smelting are reduced, and the problems of low anode efficiency of the black copper electrolysis process are solved. Meanwhile, the high-temperature high-oxygen atomized gas generated in the atomizing process provides a heat source and an oxygen source for subsequent acidolysis, so that the energy consumption is further reduced. The method has the advantages such as short process, remarkable energy conservation and emission reduction.

Comprehensive recovery method of pyrolysis polymetallic product from waste integrated circuit board

The invention relates to the field of comprehensive recovery of valuable elements such as bromine, base metal and precious metal from incineration ash, especially relates to a method for enriching precious metals from printed circuit board incineration ash by bath smelting-chlorination circulation process. The process mainly comprises pretreatment of the printed circuit board Incineration ash and circulation-chlorination enrichment process for precious metals. The crude copper, crude zinc sulfate, bromine, lead chloride and precious metal enriched slag are obtained. Compared with the traditional process, it realizes the cycle enrichment of precious metals as well as avoids the loss of valuable metals and secondary pollution caused by tail liquid discharge.

Method for enriching precious metals from printed circuit board incineration ash from molten pool by circulating chlorination

The main steps are as follows: purification, de-leading, recovery and filtration, dissolving lead, hot filtration, cooling filtration, washing and hot decomposition, silver is recycled as silver powder, lead was recovered in the form of red lead, yellow lead and chlorinated lead respectively. Compared to existing technologies, the invention adopts a wet process, the amount of waste gas and dust produced in the process of fire treatment is reduced; silver powder, red (yellow) lead and chloride lead were obtained, it can be sold as final product with high value-added features. The tail liquid produced by the process returns to the corresponding process respectively, and the tailless liquid is discharged. The pyrolysis flue gas returns to the lead removal process, flue gas treatment process is reduced, lead smoke pollution is avoided. This method has the characteristics of simple technics and pollution-free process.

Method for comprehensive recovery of silver-containing lead slag

A method of pretreatment and bromine recovery of PCB Incineration ash is disclosed that relates to the field of comprehensive recovery of valuable metals by full wet method, especially relates to a method of valuable metals and bromine recovery, precious metals enrichment in pretreatment process of PCB Incineration ash. The major steps includes alkali leaching, Cu extraction back-extraction, neutralization-precipitation to separate, Bromine evaporative crystallization, regeneration, acid pickling, Zn evaporative crystallization, removal of Zn and Cu. Compared with the traditional comprehensive recovery process of ash, the invention can separate bromine from ash and recover valuable metals such as copper, zinc and lead with the maximum extent, at the same time, the enrichment of silver and other precious metals is beneficial to the subsequent recovery of precious metals. It has high added recovery value and no tailless discharge.

Method of pretreatment and bromine recovery of PCB incineration ash

A method of recovering bromide from bromine-containing smelting ash relates to the field of high efficient separation and recovery of bromine by total wet method. It especially relates to the method of high efficiency separation of bromine salt and lead, zinc recovery of circuit board smelting ash by two-step method. It mainly comprising: sub-molten salt leaching, washing, separate Lead and zinc by adjusting the pH of industrial sulfuric acid, membrane separation and concentration, reuse of water, crude bromine salt recovery by evaporation crystallization of bromine salt. Compared with the traditional baking and recycling process of ash, the invention adopts sodium hydroxide submolten salt leaching technology and membrane separation and concentration technology, to reduce the reaction temperature and tailings discharge greatly, which has a good effect of energy saving and emission reduction.

Method of recovering bromide from bromine-containing smelting ash

A method for recovering valuable metals and simultaneously preparing ceramsite by roasting cyanide tailing belongs to the area of comprehensive recovery and high value utilization of metallurgical waste residue. In this method, cyanide tailings, bentonite, calcium chloride, coal powder and albite are mixed by ball milling according to certain weight ratio to get a mixture. After drying and roasting twice, dust is collected from the roasted ash, the obtained polymetallic ash is collected and treated. The secondary calcined material is cooled to obtain ceramsite. The invention volatilizes and recovers the valuable metal in the roasting and sintering process of cyanide tailings and directly prepares the ceramsite through reasonable batching, which achieves the effect of recycling cyanide tailings and high-value utilization, can create good economic and environmental benefits, and has significant effect of energy saving and consumption reduction.

Growing community of inventors

Beijing, China

Yufeng Wu