Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions

To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.

Removal of dolomite and potassium feldspar from apatite using simultaneous flotation with a mixed cationic-anionic collector

This study aims to investigate the effect of a cationic-anionic mixed collector(dodecyltrimethyl ammonium bromide/sodium oleate(DTAB/NaOL)on the selective separation of apatite,dolomite,and potassium feldspar.Herein,several experimental methods,including flotation experiments,zeta-potential detection,microcalorimetry detection,XPS analysis and FTIR measurements,were used.The flotation tests showed that dolomite and potassium feldspar can be successfully removed from apatite simultaneously when the molar ratio of DTAB to NaOL was 2:1 with pH 4.5.Zeta-potential and microcalorimetry detection suggested that NaOL and DTAB were adsorbed on the surface of dolomite and potassium feldspar respectively,and part of NaOL and DTAB formed co-adsorption on the surface of potassium feldspar to enhance the floatability of potassium feldspar.The XPS and FTIR spectra analysis demonstrated that the cationic collector,DTAB,was first adsorbed on the surface of potassium feldspar through electrostatic attraction in the DTAB/NaOL mixture system.Subsequently,the anionic NaOL collector and cationic DTAB collector form an electron neutralisation complex,thereby resulting in co-adsorption on the surface of potassium feldspar.NaOL was chemically reacted and adsorbed on dolomite surface,but almost no collector was adsorbed on apatite surface.Finally,the adsorption models of different collectors on mineral surface were obtained.

Simultaneous mineralization of CO_2 and recovery of soluble potassium using earth-abundant potassium feldspar

CO2 capture and storage(CCS) is an important strategy in combatting anthropogenic climate change.However,commercial application of the CCS technique is currently hampered by its high energy expenditure and costs.To overcome this issue,CO2 capture and utilization(CCU) is a promising CO2 disposal method.We,for the first time,developed a promising method to mineralize CO2 using earth-abundant potassium feldspar in order to effectively reduce CO2 emissions.Our experiments demonstrate that,after adding calcium chloride hexahydrate as an additive,the K-feldspar can be transformed to Ca-silicates at 800 C,which can easily mineralize CO2 to form stable calcium carbonate and recover soluble potassium.The conversion of this process reached 84.7%.With further study,the pretreatment temperature can be reduced to 250 C using hydrothermal method by adding the solution of triethanolamine(TEA).The highest conversion can be reached 40.1%.The process of simultaneous mineralization of CO2 and recovery of soluble potassium can be easily implemented in practice and may provide an economically feasible way to tackle global anthropogenic climate change.

Decomposition behavior of CaSO_4 during potassium extraction from a potash feldspar-CaSO_4 binary system by calcination

The extraction of potassium from a tablet mixture of K-feldspar ore and CaSO_4by roasting was studied with a focus on the effects of the decomposition behavior of CaSO_4on the potassium extraction process.The roasted slags were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy,and thermogravimetric(TG)analysis.The XRD analysis revealed that hydrosoluble mischcrystal K_2Ca_2(SO_4)_3was obtained by ion exchange of Ca^(2+)in CaSO_4and K^+in KAlSi_3O_8.Meanwhile,the intermediate product,SiO_2,separated from KAl Si_3O_8and reacted with CaSO_4to decompose CaSO_4.The SEM results showed that some blowholes emerged on the surface of the CaSO_4particles when they reacted with SiO_2at 1200°C,which indicates that SO_2and O_2gases were released from CaSO_4.The TG curves displayed that pure CaSO_4could not be decomposed below 1200°C,while the mixture of K-feldspar ore and CaSO_4began to lose weight at 1000°C.The extraction rate of potassium and decomposition rate of CaSO_4were 62%and 44%,respectively,at a mass ratio of CaSO_4to K-feldspar ore of 3:1,temperature of 1200°C,tablet-forming pressure of6 MPa,and roasting time of 2 h.The decomposition of CaSO_4reduced the potassium extraction rate;therefore,the required amount of CaSO_4was more than the theoretical amount.However,excess CaSO_4was also undesirable for the potassium extraction reaction because a massive amount of SO_2and O_2gas were derived from the decomposition of CaSO_4,which provided poor contact between the reactants.The SO_2released from CaSO_4decomposition can be effectively recycled.

钾长石混盐焙烧-浸出提钾过程研究

中国钾盐资源匮乏,而钾长石是一种重要的钾赋存形式。然而,钾长石的开发技术难度大、成本高,至今尚未实现工业化应用。为了解决钾长石开发利用过程中钾提取温度高、浸出率低等问题,该研究选取了贵州铜仁地区钾长石矿为研究对象,探究了钾长石-硫酸钠-碳酸钙混盐的焙烧-浸出过程,考察了钾长石-硫酸钠-碳酸钙的焙烧配比、焙烧温度、焙烧时间、浸取剂浓度等因素对钾长石中钾元素浸出率的影响。实验结果显示,在焙烧体系均匀混合、焙烧温度为800~900℃、焙烧时间为1 h、m(钾长石)∶m(硫酸钠)∶m(碳酸钙)为(1∶1∶6)^(1∶1∶8)条件下,以质量分数为5%NaOH溶液作为浸取液,钾的浸出率可高达99.79%。该研究提供了一条提高钾长石资源利用效率、解决钾盐资源供应问题的新途径,并为相关工业生产提供了有力的技术支持。

氧化钪对钾长石结晶釉组织结构和性能的影响

以钾长石为主晶相的釉料对解决四方相氧化锆陶瓷粘接强度不足且脆性大的问题具有良好的应用前景。本文通过DSC、XRD、SEM、硬度、强度、折射率、可见光透过率、热膨胀系数等测试,研究了Sc_(2)O_(3)含量对钾长石结晶釉结构及性能的影响。结果表明,当Sc_(2)O_(3)含量从0%(质量分数,下同)增加至10%,结晶釉的析晶温度从958.5℃降低至827.8℃,析晶能力增强,烧结后的结晶釉晶粒尺寸不断增大。随着Sc_(2)O_(3)含量的增加,结晶釉中伴随析出硅酸钪晶体,结晶釉的结晶度、努氏硬度、抗弯强度和折射率均在Sc_(2)O_(3)含量为6.67%时达到最佳,可见光透过率先减小后增大,热膨胀系数减小。

采用超导磁选回收白云鄂博矿钾板岩中钾长石试验研究

我国长石资源丰富,但富矿资源少,可被直接开采利用的优质钾长石资源并不多,绝大部分需通过富集才能达到工业应用的标准。内蒙古白云鄂博矿床是世界闻名的Fe-Nb-REO超大型矿床,钾板岩属于白云鄂博矿体上部围岩。在包头钢铁(集团)公司对该铁矿40余年的开采中,已剥离的富钾板岩作为废石在矿区大量堆存,总量超过3亿t,每年新增剥离富钾板岩达200万t,白云鄂博矿区钾板岩资源丰富,为提高白云鄂博矿物的综合利用,实现钾长石资源的可持续发展,提出从白云鄂博矿钾板岩中回收钾长石。长石矿物常与其他杂质矿物共生,特别是其中的铁等少量杂质元素,影响钾长石精矿的品质和应用,因此,有效去除高铁钾板岩中铁矿物和云母等硅酸盐类含铁杂质是提高钾长石品位的关键。对白云鄂博高铁富钾板岩进行工艺矿物学分析,确定了“破碎-磨矿-永磁磁选-超导磁选”工艺流程,针对K_(2)O品位12.66%、Na_(2)O品位为0.6%、TFe品位5.55%的钾板岩原矿,在磨矿细度为-0.074 mm占92%的条件下,经永磁磁选和超导磁选,最终获得K_(2)O品位为15.53%、回收率为54.21%、TFe品位为0.55%的钾长石精矿。结果表明,利用永磁+超导磁选工艺可以实现从钾板岩中高效回收钾长石,为综合回收利用白云鄂博矿钾板岩中的钾长石提供了新的途径。

贺州市八步区塘贡钾长石矿地质特征及开发利用

作为一种重要的非金属矿产资源,钾长石被广泛应用于陶瓷、玻璃和水泥等建材行业。本文结合贺州市八步区塘贡钾长石矿的区域地质背景,分析矿床地质特征及其成因,然后设计钾长石矿开发利用方案,为钾长石矿的开发利用提供理论指导。经详查,矿床类型为风化花岗岩型钾长石矿。钾长石深埋于侏罗纪晚期的花岗岩岩体中,强风化层及中风化层是钾长石矿的主要蕴藏区域。评估结果显示,矿区钾长石资源量丰富,矿床储量规模为中型。经设计,矿山开采规模为大型,钾长石原矿开采量为120万t/a,主要产品有2种,即钾长石精矿和建筑用砂,可以实现资源的高效利用。

鄂北风化斑状花岗岩型钾长石矿床工业指标探究

鄂北地区产出丰富的风化斑状花岗岩型钾长石矿,但缺乏专门的地质勘查规范和明确的工业指标,给该类钾长石矿的勘查开发和管理带来不便。以七尖峰岩体北部的上大南冲钾长石矿床为例,通过系统布置小竖井坑探和钻探工程,采集钾长石化学分析样品和含矿率样品,探究风化斑状花岗岩型钾长石矿床的工业指标。综合该矿床样品的统计数据和区内矿山开采的实际情况,拟定了该矿床的工业指标,即矿石有用矿物:粒径≥1 cm的钾长石斑晶;矿石有用矿物的化学成分:K_(2)O+Na_(2)O含量≥11.0%、K_(2)O/Na_(2)O比值≥2.0、Fe_(2)O_(3)含量≤2.5%;矿石有用矿物的含矿率:单工程平均≥25%。研究成果可为鄂北乃至其他地区的风化斑状花岗岩型钾长石矿床的勘查开发提供借鉴,建议及时建立该类矿床勘查的地方标准,促进钾长石矿的规范管理。

广西贺州八步区炭围钾长石矿地质特征及开发利用

我国工业上对钾长石矿产资源应用较为广泛,主要应用于玻璃和陶瓷等相关行业中。钾长石矿床类型主要分为伟晶岩岩型、岩浆岩型、沉积岩型和风化斑状花岗岩型,其中风化斑状花岗岩型钾长石矿床具有易于开采、规模大和矿石品质好的特点。广西贺州八步区炭围钾长石矿属风化斑状花岗岩型矿床。本文通过总结该矿床的主要地质特征、矿石质量以及加工工艺,探讨其矿床成因及开发利用前景,旨在为该区域寻找同类型的钾长石矿床提供帮助。

20 Years Advances in Preparation of Potassium Salts from Potassic Rocks:A Review

Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca（OH）_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,（Na, K）_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.

有机无机复混肥配施钾长石土壤调理剂对烤烟产质量及养分利用率的影响

探索菜籽油枯有机无机复混肥配施钾长石土壤调理剂对植烟土壤肥力及烤烟生长、产质量及肥料利用率的影响,为烟田施肥提供理论依据。以烤烟品种‘红花大金元’为材料,在云南昆明红壤上,开展田间试验,设置6个处理:T1(CK),施无机肥;T2,有机无机复混肥(与T1等氮磷钾);T3,有机无机复混肥+土壤调理剂(与T1等氮磷);T4,有机无机复混肥+土壤调理剂(T1减氮磷钾20%);T5,土壤调理剂+不施肥;T6,不施肥。结果表明:与CK相比,T2、T3显著增加土壤pH 0.51和0.69个单位,土壤有机质、水解性氮、有效磷、速效钾和SOC含量显著提高13.02%~43.48%,T2的TN含量较CK显著增加10.98%,T3、T4分别显著增加土壤C/N 16.02%和13.23%。T2、T3可促进烟株生长,叶面积和叶面积系数显著增加2.11%、4.50%和7.39%、23.96%。与CK相比,T2、T3烟叶上等烟比例和产值分别增加7.87%、17.66%和11.75%、29.37%;T3、T4产量较CK显著提高14.92%、8.80%。T2、T3可改善烟叶填充值与叶梗重,质地均匀、物理性质优异,且综合得分最高。与CK相比,T2、T3烟叶总糖、还原糖含量分别显著下降4.37%、4.43%和23.93%、10.9%,而T2和T3烟叶的总氮、烟碱含量较CK显著增加12.64%、11.11%及15.81%、8.12%;T2和T3烟叶钾和水溶性氯含量分别显著提高27.65%、35.94%和4.76%、14.29%,烟叶化学成分更加协调。与CK相比,T2、T3和T4显著提高氮素表观利用率13.40%~24.14%,T2、T3氮素生理利用率分别显著增加5.85%、10.75%;T2、T3和T4磷素表观利用率较CK显著增加42.49%、48.99%和16.26%,而磷素生理利用率较CK分别显著增加22.68%、34.88%和13.53%。与CK相比,T2、T3和T4钾素表观利用率分别显著提高11.88%、20.30%和7.67%,T2、T3显著增加钾素生理利用率分别为9.45%和18.87%。施菜籽油枯有机无机复混肥或有机无机复混肥配施钾长石土壤调理剂有利于提高土壤pH及提升土壤肥力,促进烟株生长,提高烟叶产量和品质,促进烤烟对氮、磷、钾肥利用。

南秦岭冷水沟铜钼金矿床年代学及其地质意义

冷水沟铜钼金矿床位于南秦岭山阳—柞水矿集区内,是南秦岭晚中生代斑岩-矽卡岩型铜(钼)矿床的代表性矿床之一。冷水沟矿区内除斑岩-矽卡岩型铜钼矿体外,还发育构造蚀变岩型金矿体,但对于铜钼矿化与金矿化之间是否存在成因联系一直存在疑惑。本次通过对斑岩-矽卡岩型铜钼矿体中辉钼矿与构造蚀变岩型金矿体中蚀变钾长石和绢云母分别进行Re-Os和^(40)Ar-^(39)Ar定年,以期能够通过成矿年代学研究来厘定两者之间的成因联系。测试结果显示,斑岩-矽卡岩型铜钼矿体的辉钼矿Re-Os等时线年龄为(147.4±8.4)Ma,构造蚀变岩型金矿体中蚀变钾长石和绢云母^(40)Ar-^(39)Ar年龄约为144 Ma,两者在误差范围内一致,说明铜钼矿体和金矿体均形成于晚侏罗世—早白垩世,是同一成矿作用的产物,并与区域内晚侏罗世—早白垩世岩浆岩具有密切的成因联系。结合区域构造演化特征,本次研究结果显示冷水沟铜钼金矿床形成于晚中生代秦岭造山带构造体制转变的动力学背景。同时,冷水沟地区金矿成矿时代的限定也表明南秦岭地区存在晚侏罗世—早白垩世金矿成矿作用。

辽西万家沟地区钾长花岗岩年代学、岩石地球化学特征及其地质意义

为厘定辽西万家沟地区钾长花岗岩的形成时代及成因,对其进行了年代学和元素地球化学研究。结果表明:钾长花岗岩U-Pb同位素年龄为(155.9±1.8)Ma,岩石具有富Si、Al、Na、K,贫Mg、Ca、Ti等特征,轻稀土元素相对富集,大离子亲石元素Rb、Th、U、Ta等相对亏损,高场强元素Ba、Sr、Zr、Hf等相对富集,具较弱的铕和铈负异常。结合区域构造背景,认为研究区钾长花岗岩形成于晚侏罗世古太平洋板块向华北克拉通持续俯冲的构造环境背景,成因可能为古太平洋板块向欧亚板块俯冲导致幔源岩浆上侵使地壳发生部分熔融有关。

基于响应曲面法的钾长石提钾优化工艺

为了确定K_(2)O浸出钾长石的最佳工艺条件,采用基于Box-Behnken设计的响应曲面法考察水热过程中水热温度、水热时间、液固比、Ca与Al+Si摩尔比4个因素的交互作用对K_(2)O提取率的影响.通过实验设计、方差分析、模型拟合、参数优化和结果验证等步骤确定了最优工艺条件.结果表明:水热温度以及Ca与Al+Si摩尔比的交互作用对K_(2)O提取率的影响最为显著;提取K_(2)O的最优工艺条件为:水热温度280℃,水热时间7.22 h,液固质量比20,Ca与Al+Si摩尔比1.5;最优工艺条件下K_(2)O提取率的预测值为100%,实验结果的平均值为99.14%,预测值与实验结果平均值的一致性较好.

氮磷钾减量配施钾长石土壤调理剂对烤烟产质量及养分利用率的影响

【目的】探明氮磷钾减量配施钾长石土壤调理剂对烤烟产质量及肥料利用率的调控效应。【方法】以烤烟品种K326为材料,采用大田试验,研究烟农常规施肥T1(CK1)、土壤调理剂+烟农常规施肥(T2)、土壤调理剂+减施氮磷钾20%(T3)、土壤调理剂+减施氮磷钾40%(T4)、土壤调理剂+不施肥(T5)、不施肥(T6,CK2)6种施肥方式对云南曲靖黄壤土壤养分含量及烤烟产质量、氮磷钾利用率的影响。【结果】与T1(CK1)相比,T2、T3显著提高土壤pH、有机质、水解性氮、有效磷、速效钾、交换性钙和交换性镁含量3.07%~42.28%;T2、T3促进烟株生长明显,叶面积和叶面积系数显著增加4.37%、5.65%、3.62%、5.26%;T2、T3增产率分别为11.82%、17.13%,其产值分别显著提高32.91%、28.99%;T2、T3和T4中部烟叶总糖、还原糖和氧化钾升高,总氮、烟碱含量下降,烟叶化学成分更加协调;T2、T3和T4显著提高氮素表观利用率33.43%~36.21%,增加氮素生理利用率31.49%~33.18%;T2、T3和T4磷素表观利用率显著增加14.09%、6.62%和4.07%,而磷素生理利用率分别显著增加20.14%、13.58%和5.62%;T2、T3和T4钾素表观利用率分别显著提高10.53%、4.39%和3.97%,而显著增加钾素生理利用率分别为9.94%、4.72%和2.79%。【结论】施钾长石土壤调理剂有利于改良土壤pH及土壤肥力提升,且在当前氮磷钾施用量(N 82.5 kg/hm 2、P 2O 5123.75 kg/hm 2、K 2O 247.5 kg/hm 2)的基础上,等量或减施氮磷钾20%并配施钾长石土壤调理剂可促进烟株生长,提高烟叶产量和品质,促进烟株对氮、磷、钾肥的吸收和利用。

镁、硼、氯肥配施土壤调理剂对烤烟光合特性及产质量的影响

【目的】探讨镁、硼、氯肥配施钾长石土壤调理剂对烤烟的效应,为文山烤烟生产配方施肥和化肥减量提供技术支撑。【方法】以烤烟品种云烟97为材料,在文山喀斯特烟区红壤上,采用L_(9)(3^(4))正交大田试验,研究镁、硼、氯肥配施钾长石土壤调理剂对烤烟土壤、营养生长、光合特性及产质量的影响。【结果】与T1(CK)相比,根区施用镁、硼、氯肥及钾长石土壤调理剂均不同程度提升了土壤pH,提高了有机质、水解性氮、有效磷、速效钾、交换性钙、交换性镁、有效硼和水溶性氯含量,其中以处理T4、T5和T8较优;同时可显著提高烤烟叶片净光合速率(P_(n))、气孔导度(G_(s))、胞间CO_(2)浓度(C_(i)),显著降低速率(T_(r)),以处理T5、T8效果较优;而且可促进烤烟生长发育,提高烟叶上等烟比例、产量和产值,其中处理T5、T8产值较T1(CK)分别显著提高15.01%、21.36%。与T1(CK)相比,各处理对中部烟叶总糖、还原糖、总氮、烟碱、氧化钾、水溶性氯、钙、镁和硼均有一定改善作用,尤以处理T2、T5、T8烟叶化学成分协调性最好。【结论】在文山喀斯特烤烟栽培区,组合施用硫酸镁150 kg/hm^(2),硼砂15~30 kg/hm^(2)、氯化钾60~90 kg/hm^(2)及钾长石土壤调理剂600~900 kg/hm^(2),能改善土壤pH和土壤主要有效态养分含量,可提升烤烟光合作用,促进生长发育,提高经济效益,改善烟叶化学成分协调性,具有良好的推广潜力。

陶瓷球为磨矿介质的长石磨矿动力学研究

以0.3~0.6 mm的钾长石作为研究对象,探究以陶瓷球为磨矿介质的磨矿动力学。在磨矿介质为陶瓷球和钢球的球磨机内进行磨矿动力学试验,得到不同粒级的筛上累计产率并计算得到对应的ln(R_(0)/R),在Origin中拟合得到两者磨矿动力学方程。结果表明,两种磨矿介质均符合一阶磨矿动力学模型,且粒径d和磨矿动力学参数k呈幂函数相关。以陶瓷球作为磨矿介质,在介质充填率为40%的情况下,磨矿动力学方程为R=R_(0)exp[-(0.00506+0.62238d^(1.49467))t]。当介质充填率或磨矿介质质量相同时,陶瓷球较钢球磨矿速度更慢,且在较粗粒级时尤为明显。因此,在实验室阶段陶瓷球作为磨矿介质对钾长石的破碎能力具有一定的局限性。

贺州里松矿区大狼冲钾长石矿地质特征及矿床成因

里松矿区钾长石矿赋存于花岗岩风化壳中,属风化残余矿床。文章通过总结贺州市里松矿区大狼冲钾长石矿的矿床特征、矿体特征以及矿石质量,分析矿床成因以及控矿因素,旨在为该区域寻找同类钾长石矿提供帮助。

六偏磷酸钠对钾长石和赤铁矿的分散作用机理

通过沉降率实验、浊度实验、Zeta电位测定、溶液化学分析以及扩展DLVO理论分析,揭示了六偏磷酸钠对微细粒钾长石和赤铁矿的分散作用。结果表明,六偏磷酸钠电离产生的Na_(m)(PO_(3))_(n)^(m-n)(m<n)阴离子会以螺旋状长链聚合体形式包裹在矿粒表面,形成厚厚的大分子亲水保护膜;水解生成的HPO_(4)^(2-)会吸附在矿粒表面,导致矿粒表面电位降低、矿粒间静电斥力以及空间位阻效应增强,矿粒达到稳定凝聚态需要克服的势垒增大,矿粒间非选择性团聚现象减弱,分散体系稳定性显著增强。