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91.
活性炭从硫脲浸出液中回收金的工艺研究 总被引:6,自引:0,他引:6
本文研究了在酸性硫脲浸出液中活性炭回收金的工艺过程,实验表明,在该浸出液中活性炭对金具有较高的吸附速度、吸附率和吸附容量并易于解吸,为工业应用提供了可靠的技术依据。 相似文献
92.
研究了二异氰酸酯与壳聚糖的交联反应,其产物与壳聚糖相比,酸溶解度由82.04%降到58.08%。DSC曲线表明,交联产物的热稳定性明显提高,对低价重金属离子(Hg 相似文献
93.
The sorption of AuCl4
−,AuCl2
− and Au(S2O3)3- on δ-MnO2 was investigated at pH2–11.6, 0.01 mol/L and 0.1 mol/L NaNO3 solutions. At pH 4 in two electrolyte strength solutions, Au sorption densities on δ-MnO2 are 0.18–0.21 and 0.28μmoL/m2 for AuCl4
− and Au(S2O3)2
3-, respectively, and the Au surface coverage is approximate to or lower than 1%. This adsorption of the two Au complexes decreases
as the solution pH increases, which conforms to the sorption regularity of the anion on δ-MnO2. The Au sorption decreases in the sequence of Au(S2O3)2
3- >AuCl4
− >AuC12
−. The intrinsic equilibrium constants (logK
int) of the three Au complexes are 1.17–2.7, much higher than those of Cu and Cd. The hydrolysis products of AuCl4
- are preferentially adsorbed by δ-MnO2 and the inner-sphere Au-surface complexes are formed on the surface.
Project supported by the National Studying-abroad Foundation, the National Natural Science Foundation of China (Grant No.
49573200) and the Australian Mining Industry. 相似文献
94.
Role of coal type and rank on methane sorption characteristics of Bowen Basin, Australia coals 总被引:5,自引:0,他引:5
The effect of coal composition, particularly the organic fraction, upon gas sorption has been investigated for Bowen Basin and Sydney Basin, Australia coals. Maceral composition influences on gas retention and release were investigated using isorank pairs of hand-picked bright and dull coal in the rank range of high volatile bituminous (0.78% Ro max) to anthracite (3.01% Ro max). Adsorption isotherm results of dry coals indicated that Langmuir volume (VL) for bright and dull coal types followed discrete, second-order polynomial trends with increasing rank. Bright coals had a minimum VL at 1.72% Ro max and dull coals had a minimum VL at 1.17% Ro max. At low rank, VL was greater in bright coal by about 10 cm3/g, but as rank increased, the bright and dull trends converged and crossed at 1.65% Ro max. At ranks higher than 1.65% Ro max, both bright and dull coals followed similar trends. These competing trends mean that the importance of maceral composition on VL varies according to rank. In high volatile bituminous coals, increases in vitrinite content are associated with increases in adsorption capacity. At ranks higher than medium to low volatile bituminous, changes in maceral composition may exert relatively little influence on adsorption capacity. The Langmuir pressure (PL) showed a strong relationship of decreasing PL with increasing rank, which was not related to coal type. It is suggested that the observed trend is related to a decrease in the heterogeneity of the pore surfaces, and subsequent increased coverage by the adsorbate, as coal rank increases. Desorption rate studies on crushed samples show that dull coals desorb more rapidly than bright coals and that desorption rate is also a function of rank. Coals of lower rank have higher effective diffusivities. Mineral matter was found to have no influence on desorption rate of these finely crushed samples. The evolution of the coal pore structure with changing rank is implicated in diffusion rate differences. 相似文献
95.
96.
97.
研究了pH 和总钼酸根浓度对海水中钼酸根在针铁矿上吸附的影响。钼酸根在针铁矿上的吸附等温线为S型。假设海水中钼酸根在针铁矿表面的吸附,是在双电层的内Helmholt 层中的能量相等的不同位置上进行的,并考虑到吸附的钼酸根之间存在着横向相互作用,由此推导得到的吸附等温式可描述钼酸根在针铁矿上的S型吸附等温线,并计算得到钼酸根在针铁矿上的最大吸附量为4 .76 ×10- 5mol/g。钼酸根在针铁矿上的吸附受溶液pH影响,吸附密度随pH 的增加而降低。加入到海水中的钼约有20 % 可被水合氧化铁的清除作用所转移。 相似文献
98.
Anitha Senthamizhan Brabu Balusamy Doriana Debellis Jose Alejandro Heredia-Guerrero Giorgio Mancini Riccardo Carzino Luca Ceseracciu Athanassia Athanassiou Despina Fragouli 《洁净——土壤、空气、水》2023,51(1):2200284
Conversion of waste biomass into valuable functional materials accomplishes the concept of circular economy in the development of sustainable waste management, and also recovery of such resources possibly reduces the requirement of feedstocks. In this scenario, the development of methodologies toward the direct conversion of the raw biomass into solid adsorbent materials without the use of any templates is highly desirable, but exceptionally challenging due to the complexity of the process. Here the direct synthesis of 3D porous carbon traps by a simple, cost-effective, and template-free process starting from a kitchen-based recipe and fermented food waste is described. Precisely, a robust carbon trap is formed with a spongy structure and highly interconnected hierarchical pores after the pyrolysis of a rice-based foam in the air. The developed materials float on water and interact efficiently with cationic dyes at static conditions. Importantly, such performance of the 3D carbon traps is not affected in the presence of anionic dyes, indicating the excellent selectivity towards the adsorption of cationic dyes. The adsorbent can be easily recovered and reused for up to 3 cycles without releasing any byproducts, thus, without causing hazardous risk of any secondary pollution to the environment. 相似文献
99.
100.
金的地球化学勘查基于金的准确测定,地球化学样品中金含量通常处于ng/g水平,需先进行分离富集,再采用电感耦合等离子体质谱法(ICP-MS)或石墨炉原子吸收光谱法(GFAAS)进行测定。当前,隐伏矿床勘查是地球化学探测技术的发展前沿,金活动态提取技术是寻找隐伏金矿的有效手段之一。相比于全量分析,金的活动态含量更低,需要解决选择性提取、高效预富集与准确测定等一系列难题。本文采用柠檬酸铵与土壤中黏土矿物及次生矿物作用促使吸附和可交换组分的金进入提取液,以硫脲和硫代硫酸钠络合金使活动态金向提取液中扩散,达到选择性提取的目的,建立了提取液中金的预富集及ICP-MS测定方法。实验确定的分析条件为:采用5g/L柠檬酸铵-2g/L硫脲-5g/L硫代硫酸钠为提取剂,提取时间24h,在酸性硫脲介质下用活性炭富集金,金吸附率可达89.6%~109.2%,灰化解吸温度为650~700℃。本方法检出限为0.05ng/g,相对标准偏差(RSD)为9.4%~10.2%,加标回收率为91.2%~93.4%。与已报道的硫酸铁-硫脲-硫代硫酸钠溶液提取再GFAAS测定的方法相比,本方法具有检出限低、测试线性范围宽、测试速度快的优势;应用于森林覆盖区黑龙江东安金矿区地球化学探测试验,金活动态异常与隐伏金矿位置一致。 相似文献