(1. 中南民族大學(xué) 資源與環(huán)境學(xué)院 湖北省重金屬污染防治工程技術(shù)研究中心，武漢 430074；
2. 中南民族大學(xué) 催化轉(zhuǎn)化與能源材料教育部重點(diǎn)實(shí)驗(yàn)室，武漢 430074)
摘 要: 探究了球磨預(yù)處理銅冶煉煙灰中As與有價(jià)金屬的高效分離，并對(duì)比研究球磨及堿性介質(zhì)中球磨預(yù)處理對(duì)煙灰中As分離浸出效果影響。結(jié)果表明：?jiǎn)为?dú)采用球磨預(yù)處理會(huì)抑制煙灰中As的浸出，與未球磨煙灰相比，浸出率由56.01%降至32.85%；而堿性介質(zhì)的加入可顯著提高As浸出率，浸出率則由56.01%升至78.52%，最優(yōu)工藝參數(shù)為：NaOH與煙灰質(zhì)量比(mNaOH:mAsh)=0.5:1、球磨活化60 min(堿性介質(zhì)下球磨預(yù)處理(50±5) min后，投加入一定量的乙醇研磨(10±5) min)、轉(zhuǎn)速600 r/min。另外，采用該方法處理后，煙灰中Cu、Zn、Pb、Cd基本未被浸出，且浸出殘余固體物中As含量由5.74%降低至0.13%。SEM和粒徑分析表明：球磨可使顆粒表面產(chǎn)生缺陷，減小煙灰粒度，增大反應(yīng)比表面積，促進(jìn)界面?zhèn)髻|(zhì)，提高As浸出率。XRD和XPS結(jié)果表明：球磨過(guò)程中局域產(chǎn)生高溫高壓，誘導(dǎo)固-固反應(yīng)，As2O3等與NaOH反應(yīng)轉(zhuǎn)化為可溶性的砷酸鹽，部分PbSO4在局部高溫下最終分解為PbO，進(jìn)一步強(qiáng)化浸出過(guò)程中As與有價(jià)金屬的高效分離，該方法為煙灰無(wú)害化及資源化的利用提供了理論依據(jù)。
關(guān)鍵字: 銅冶煉煙灰；球磨；化學(xué)反應(yīng)；活化；界面?zhèn)髻|(zhì)；選擇性浸出
（1. Hubei Province Engineering Research Center for Control and Treatment of Heavy Metal Pollution, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, China;
2. Key Laboratory of Catalysis Conversion and Energy Materials Chemistry, Ministry of Education, South-Central University for Nationalities, Wuhan 430074, China）
Abstract:The high-efficiency separation of arsenic and valuable metals in copper smelting soot strengthened by the ball milling pretreatment were investigated. The results show that the ball milling pretreatment alone can inhibit the leaching of As in soot. Compared with the unmilled soot, the leaching efficiency is reduced from 56.01% to 32.85%. However, the addition of NaOH can significantly increase the As leaching efficiency from 56.01% to 78.52%. The optimal process parameters are as follows: the mass ratio of NaOH to ash (mNaOH:mAsh) of 0.5:1, activation time of ball mill of 60 min (after ball milling pretreatment for (50±5) min in alkaline medium, and then milling with ethanol in sequence), the rotation speed of 600 r/min. Besides, Cu, Zn, Pb and Cd in the soot is basically not leached after treatment by this method, and the As content in the leaching residual solid is reduced from 5.74% to 0.13%. The SEM and particle size analysis show that ball milling can create defects on the surface of the particles, reduce the particle size of the soot, increase the specific surface area of ？？the reaction and promote the mass transfer of the interface. Therefore, the leaching efficiency of As is dramatically enhanced. The results of XRD and XPS show that high temperature and high pressure are generated in the specific area during the ball milling process, inducing the solid-solid reaction: the oxidation state of As2O3 after reacting with NaOH converges into soluble arsenate, finally. And decomposition of parts of PbSO4 into PbO in a local high temperature environment, which further enhances the efficient separation of As and valuable metals during the leaching process. This study provides a theoretical basis for the harmlessness, and the resource utilization of arsenic-containing materials is produced by copper smelting industry.
Key words: copper smelting soot; ball milling; chemical reaction; activation; interface mass transfer; selective leaching
