炼锑砷碱渣中锑砷分离及动力学研究

研究了砷碱渣中锑和砷的分离及过程动力学。采用正交试验考察了砷碱渣水热浸出时固液比、搅拌速度、浸出温度以及时间对砷浸出率的影响。结果表明,浸出砷的最佳条件为:固液比1∶4、浸出温度90℃、搅拌速度600r/min、浸出时间60min。砷浸出过程动力学方程为1-(1-x)1/3=Mkc/br0ρt,反应活化能666.57kJ/mol,属于化学反应控制。

冶炼厂高砷锑氧化物的锑砷分离和利用

许多冶炼厂产出大量高砷锑氧化物废物,严重污染环境。本研究采用简单、低成本工艺处理此,为锑冶炼厂提供合格的锑原料,使废物有效地资源化。

锑砷分离时毒砂抑制剂的探讨

毒砂是较易氧化的硫化矿。适当氧化以前可浮性较差。但锑砷分离时仍然需要抑制剂的抑制作用。根据毒砂易氧化的性质,Ca(OCl)_2和KMnO_4等氧化剂也可抑制毒砂。由于其选择性差,对锑砷分离的效果不很理想。在非氰抑制剂当中,ZnSO_4与Na_2S_2O_3的混合使用稍比ZnSO_4与Na_2SO_3混合使用弱一些,但不影响辉锑矿的浮游,选择性好。是本矿石可取的组合抑制剂。

金属滤料收尘器在烟气砷锑分离中的应用

本文介绍了高砷锑烟尘在冶炼时产出烟气的特点,针对该特点提出了在烟气中进行砷锑分离的方案,并在相关冶炼厂中开展试验。文中重点介绍了金属滤料收尘器在烟气砷锑分离系统应用时的设计要点,并在实际使用中达到了预期目的,为同类项目设计提供了参考意义。

砷碱渣中砷锑碱梯级分离及金属砷回收工艺

针对当前砷碱渣处理过程砷碱分离效果差、分离的砷酸钠或钙砷渣安全处置难等问题,提出“水浸-水热沉砷-碳热还原”回收金属砷新工艺。以湖南某冶炼厂砷碱渣为对象,开展砷碱渣水浸砷锑分离、氧化钙水热沉砷砷碱分离、沉砷渣碳热还原回收金属砷等环节的工艺研究。研究结果表明:在浸出时间30 min、液固比3:1、浸出温度45℃、搅拌速度600 r/min的水浸条件下,砷、锑浸出率分别为95.3%和1.6%。在初始pH=11、水热温度180℃、反应时间6 h、Ca/As物质的量比为24:1的水热沉砷条件下,沉砷率达95.3%,沉砷渣主要为碳酸钙、氢氧化钙和砷酸钙。在碳粉添加量10%、温度1 000℃、还原时间3 h条件下,砷挥发率为93.1%,挥发产物砷质量分数达92.0%。砷碱渣“水浸-水热沉砷-碳热还原”新工艺,具有可实现砷锑碱梯级分离、砷以无毒的单质砷回收、沉砷剂氧化钙可循环使用、全流程未引入难处理的阴阳离子等优点。

钙化转型-碳热还原从砷碱渣中分离制备砷锑

锑冶炼砷碱渣是锑冶炼过程中产生的危险固体废渣,目前对其进行资源化综合利用较为困难,存在砷锑回收率低、分离不完全、可能造成二次污染等问题。为解决这些问题,本研究以砷碱渣为原料,采用钙化转型-碳热还原工艺对砷碱渣进行处理。热力学研究结果表明,钙化转型拉大了砷锑还原所需要的温度区间,有利于还原过程中砷锑的分离。在最佳条件下,砷碱渣中的砷和锑的钙化率分别达到99.67%和98.74%;真空条件下对钙化渣还原可以有效分离砷、锑,碳热还原过程中钙化渣中砷、锑的还原率均超过99%,反应后经一次真空蒸馏提纯,砷、锑的纯度均能达到99.8%。与传统砷碱渣处理方法相比,该方法能更好地分离回收砷、锑,且制备的砷、锑纯度更高。

氧压碱浸-水洗分离高砷锑烟尘中砷锑的研究

以铅阳极泥火法处理过程产出的高砷锑烟尘为处理对象,结合氧压碱浸试验和XRD、ICP-OES等表征方法,探究氧分压、液固比、氢氧化钠浓度、浸出温度、浸出时间对砷、锑、铅分配行为的影响。结果表明,以氧分压2.0 MPa、液固比10 mL/g、氢氧化钠浓度2 mol/L、浸出温度200℃、浸出时间2 h的条件对高砷锑烟尘进行氧压碱浸,浸出渣再经水洗处理,可使烟尘中99.5%以上的砷进入溶液,锑、铅、铋进入浸出渣,水洗渣中砷含量小于0.5%,可制备高品质锑白产品,实现了砷和锑的深度分离。

富砷锑金矿石浮选分离试验研究

对某富砷锑金矿石进行了浮选分离试验研究。在弱酸性条件下,以硝酸铅作活化剂,以丁基铵黑药作捕收剂,采用浮锑抑砷工艺,最终获得含锑63.18%、回收率95.05%的锑精矿和含金9.02 g/t、含砷9.32%、金回收率为65.06%、砷回收率为64.97%的金砷混合精矿。

高砷锑烟尘中砷、锑分离研究进展

以不同价态砷、锑氧化物挥发性和水相热力学性质区别为切入点,综述了高砷锑烟尘中砷、锑物相的分离方法。分析了焙烧法和浸出沉淀法分离砷、锑的机理、过程和效果,并对各方法的优缺点进行了讨论。

砷锑烟灰NaOH常压碱浸分离砷锑的工艺

铅阳极泥火法处理过程中产生的砷锑烟灰对环境的危害巨大,但其中锑作为有价金属又需要回收利用,因此对砷锑烟灰进行砷锑分离具有实际意义。采用常压碱浸的方式对砷锑烟灰的分离进行了实验研究。首先考察了常压碱浸过程中添加双氧水对砷锑分离的影响,结果发现添加双氧水对砷锑分离的影响不明显,因此后续选择不使用氧化剂进行碱性浸出。其次考察了浸出温度、NaOH浓度、液固比和浸出时间等因素对砷锑分离的影响,结果表明:在70℃、NaOH浓度60 g/L、液固比(mL/g)4∶1、搅拌转速恒定为400 r/min,浸出90 min的条件下,砷浸出率达到93.92%,锑浸出率为2.74%,该工艺可以达到砷锑有效分离的目的。

西藏某含高砷锑金矿石浮选回收锑金试验研究

对西藏某含高砷锑金矿石进行了选矿试验研究。试验采用的工艺流程:优先浮选锑,使锑砷分离,从分离浮选后的尾矿中回收金。试验指标:锑精矿品位63.30%(含As 0.48%,Pb 0.14%),锑回收率59.74%;金精矿品位9.08 g/t,金回收率88.19%。试验获得的锑精矿达到一级品级,并充分回收了金。

锑冶炼砷碱渣有价资源综合回收工业试验研究

提出了锑冶炼砷碱渣水热浸出-锑盐氧化-浓缩结晶回收锑、砷、碱新工艺,并进行了工业试验研究。结果表明：以含锑9.86%、砷4.51%的历史堆存锑冶炼二次砷碱渣为原料,在液固比2∶1、浸出温度95℃条件搅拌浸出60 min,再在温度60-80℃时双氧水氧化作用60 min处理后,可实现锑砷的高效分离。研究优化了选择性分步浓缩结晶工艺,在高于80℃条件下反应180 min一步结晶,再冷却至60℃进行两步结晶处理后,实现碱和砷的分离。获得的碱和砷酸钠盐产品利用微波干燥技术,获得了均匀干燥的产品。新工艺实现了工业化应用,砷碱渣处理锑回收率95.27%、砷回收率95.21%;为砷碱渣的资源化处理提供了重要新方法。

从高砷高锑烟灰中综合回收有价金属工艺研究

文章介绍了以Na2S作浸出剂，在强碱性介质中浸出高砷高锑烟灰中砷和锑，在保持碱性条件下，用氧化剂氧化浸出液，使砷、锑分离，分别制取焦锑酸钠NaSb(OH)6和砷酸钠Na3AsO4; 而烟灰中的铅、银、铜富集于浸出渣中得以回收。

久经考验,无可替代

在小型试验研究的基础上进行了砷碱渣砷锑分离中试研究，验证水热浸出-价态调控氧化脱锑工艺的可行性，并得到最佳工业生产操作参数：砷碱渣的破碎粒度5mm，浸出温度95℃，一次浸出时间60min，二次浸出时间180min，一次浸出渣的球磨粒度50目，液固比3：1，双氧水的加入量14‰，总氧化时间60min，双氧水的投加时间20min，氧化温度80℃。在该条件下，砷的浸出率为97．72％，锑的回收率为96．74％。

铅阳极泥湿法预处理工艺研究

介绍了湿法处理铅阳极泥的工艺,确定了铅阳极泥氧化焙烧条件。对氧化焙烧后的铅阳极泥加与不加氧化剂氯盐浸出工艺,硫化碱浸出、氧化分离锑砷工艺进行了研究。研究表明:氯盐浸出工艺Sb、Bi、Cu直收率分别达60%、89%、86%以上;硫化碱浸出、氧化分离锑砷工艺锑砷产品不好处理。

Separation of arsenic from arsenic-antimony-bearing dust through selective oxidation-sulfidation roasting with CuS

The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.

Recovery of antimony from antimony-bearing dusts through reduction roasting process under CO–CO_2 mixture gas atmosphere after firstly oxidation roasted

This paper mainly investigated the antimony recovery from antimony-bearing dusts through reduction roasting process after the dust firstly oxidation roasted.CO–CO2 mixture gas was used as reducing agent,and the antimony-containing phase was reduced into Sb4O6,volatilized into smoke,and finally recovered through the cooling cylinder.The antimony recovery rate increased from 66.00 wt%to 73.81 wt%in temperature range of 650 to 800°C,and decreased with temperature increased further to 900°C due to the reduction of Sb4O6 to the nonvolatile Sb.Similarly,the CO partial pressure also played a double role in this test.Under optimized conditions of roasting temperature of 800°C,CO partial pressure of 7.5 vol%and roasting time of 120 min,98.40 wt%of arsenic removal rate and 80.40 wt%antimony recovery rate could be obtained.In addition,the“As2O3”product could be used for preparing ferric arsenate which realized the harmless treatment of it.

Preparation of elemental As from As-Sb fly ash using continuous reductive method with additive of lead oxide

To recycle arsenic from an As-Sb fly ash,a newly continuous reductive method for obtaining elemental As with additive of PbO was proposed.In the first reduction stage,PbO promoted the As segregation from the As-Sb fly ash,due to which most As volatilized and Sb retained in roasted residues in phases of As-Sb-Pb-O and As-Sb-Pb alloy.With the increase of PbO and reductant amounts,the Sb fixation rate increased in the first reduction stage,and further the Sb content in the elemental As obtained from the second reduction stage decreased.After being roasted for 30 min at 550℃ with the addition of 20%activated carbon and 12%PbO in the first reduction stage,the As volatilization rate and Sb fixation rate from the As-Sb fly ash reached 92.86%and 79.38%,respectively.Then through the second reduction of the volatile matters at 650℃,the As and Sb contents in the obtained elemental As reached 99.07 wt%and 0.22 wt%respectively,indicating that the obtained As could be used to prepare high purity As,thereby rendering the As-Sb fly ash recycling.

Separation of arsenic and antimony from dust with high content of arsenic by a selective sulfidation roasting process using sulfur

The separation of arsenic and antimony from dust with high content of arsenic was conducted via a selective sulfidation roasting process.The factors such as roasting temperature,roasting time,sulfur content and nitrogen flow rate were investigated using XRD,EPMA and SEM-EDS.In a certain range,the sulfur addition has an active effect on the arsenic volatilization because the solid solution phase（（Sb,As）2O3）in the dust can be destroyed after the Sb component in it being vulcanized to Sb2S3 and this generated As2O3 continues to volatile.In addition,an amorphization reaction between As2O（3 ）and Sb2O（3 ）is hindered through the sulfidation of Sb2O3,which is also beneficial to increasing arsenic volatilization rate.The results show that volatilization rates of arsenic and antimony reach 95.36%and only 9.07%,respectively,under the optimum condition of roasting temperature of 350℃,roasting time of 90 min,sulfur content of 22%and N2 flow rate of 70 m L/min.In addition,the antimony in the residues can be reclaimed through a reverberatory process.

铅阳极泥湿法预处理试验研究

介绍了湿法处理铅阳极泥的工艺研究,分析了湿法处理铅阳极泥的原理,对氧化焙烧后的铅阳极泥加与不加氧化剂氯盐浸出工艺、硫化碱浸出、氧化分离锑砷工艺进行了研究。研究表明:氯盐浸出工艺存在着金银的损失,加氧化剂浸出铅阳极泥金有5.28%,银有8.15%,不加氧化剂浸出铅阳极泥银有5.01%进入溶液难于回收;硫化碱浸出、氧化分离锑砷工艺锑砷产品不好处理。