Mineral sulphide-lime reactions and effect of CaO/C mole ratio during carbothermic reduction of complex mineral sulphides

Mineral sulphide (MS)-lime (CaO) ion exchange reactions (MS + CaO = MO + CaS) and the effect of CaO/C mole ratio during carbothermic reduction (MS + CaO + C = M + CaS + CO(g)) were investigated for complex froth flotation mineral sulphide concentrates. Phases in the partially and fully reacted samples were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The primary phases during mineral sulphide-lime ion exchange reactions are Fe₃O₄, CaSO₄ Cu₂S, and CaS. A complex liquid phase of Ca₂CuFeO₃S forms during mineral sulphide-lime exchange reactions above 1173 K. The formation mechanisms of Ca₂CuFeO₃S liquid phase are determined by characterising the partially reacted samples. The reduction rate and extent of mineral sulphides in the presence of CaO and C increase with the increase in CaO/C ratio. The metallic phases are surrounded by the CaS rich phase at CaO/C > 1, but the metallic phases and CaS are found as separate phases at CaO/C < 1. Experimental results show that the stoichiometric ratio of carbon should be slightly higher than that of CaO. The reactions between CaO and gangue minerals (SiO₂ and Al₂O₃) are only observed at CaO/C > 1 and the reacted samples are excessively sintered.     

BT303CuS易切削不锈钢轧件劈头的研究

对BT303CuS易切削不锈钢热轧过程中产生的轧件头部开裂原因进行了分析,发现轧件劈头与钢中硫化物的形态有关,利用热模拟实验研究了加热温度对轧件硫化物形态变化影响,在此基础上确定出最佳加热温度范围是1200～1280℃.同时采取了控制轧件头部冷却水、使用新型导卫及增设工序飞剪等一系列工艺措施,显著减少了轧制缺陷,中间废品率由5.67%下降到1.38%,使宝钢股份特钢事业部长型材生产线形成批量生产该钢的能力.     

安徽南陵西周硫化矿冶铜技术的研究

本文根据考古发现，研究了安徽南陵西周硫化矿冶铜技术，并分析了我国发明这一技术的时间、意义、科学价值及其对日本青铜文化的影响     

氢氧化钠水溶液吸收羰基硫反应级数研究

常压下温度为３０～５０℃，用鼓泡反应器测定了羰基硫（ＣＯＳ）在浓度为１．３１３０～４．４０３８ｋｍｏｌ／ｍ３ＮａＯＨ水溶液中的吸收速率，通过理论分析得到该吸收为一级不可逆快反应吸收过程。     

铂族元素镍铳试金预富集中子活化分析方法研究

采用镍锍试金法,硫化镍萃取铂族元素。然后用6M盐酸溶解镍锍扣,过滤酸溶液。用中子活化方法分析铂族元素残渣。该方法检出限在ppb水平。     

钠掺杂反式聚乙炔中孤子晶格的局域振动模

从包含电子－电子相互作用和外库仑势的ＳＳＨ推广模型出发，计算了在各个掺杂浓度（杂质等距离分布）下反式聚乙炔中孤子晶格周围的局域振动模。计算结果表明：在掺杂浓度为１．６７％时，反式聚乙炔存在１０个局域模；在浓度为３．３３％～１０．００％时，存在８个局域模；而在浓度大于１３．３３％时，所有的局域模都消失变为扩展模。     

Researches on Mechanism of Treatment Technology of Wastewater from Viscose Fibre Production

This paper centres on the mechanism of wastewater treatment technology for viscose fibre production, in-volving the removal of sulphide (S2-), zinc(Zn2+), and organic substances( CODer), and meanwhile, de-termines the optimal strategy for wastewater treatment of Shanghai No. 1 Chemical Fibre Factory. Hydrosul-phuric acid is a weak acid, and in a certain range of pH value(pH < 8 .18) the concentration of free S2- is below 1 mg/1. The H2S gas can be removed by intro-ducing compressed air. Actually, when pH < 3, the concentration of sulphide in wastewater can meet the discharge standard. As to zinc (Zn2+), owing to its amphiprotic nature, it can be precipitated completely while pH value is within 8.24-10.5 . With the com-bined method of oxidation and coagulation, the average removal of CODer reaches 81.37% , and the concentra-tion of CODer In the effluent is about 50mg/1 under the best conditions: both the concentrations of oxidant and coagulant are about 60 ppm and the pH is 7 .