Acid-soluble Potassium Research Articles

Recovery lithium and potassium from lepidolite via potash calcination-leaching process

A new comprehensive way to extract lithium and potassium from lepidolite through calcination process with the additive of K2CO3 has been proposed. By using flowing water vapor, the lepidolite concentrate mixed with 58.5% of K2CO3 could generate acid-soluble potassium aluminum silicate (KAlSiO4) and water-soluble lithium/potassium silicate (Li2SiO3/K2SiO3) at 850 °C for 2 h. Additionally, 80% of fluorine could be removed. The reaction feasibility between lepidolite ore and K2CO3 was firstly evaluated through thermodynamic calculation. The decomposition mechanism was explored through XRD and TG-DSC analysis. The experimental results reveal that the decomposition of lepidolite undergoes following phase transformation: trilithionite phase → lepidolite phase → KAlSi2O6 → KAlSiO4. As the desilication process proceeds, silicon is given off and forms lithium/potassium silicate. Through a water leaching process, soluble Li2SiO3/K2SiO3 could be separated from KAlSiO4. The extraction efficiency of Li and K could severally reach 95.52% and 95.70% from soluble silicates through water leaching process, under the optimum conditions. Then the residue KAlSiO4 could be easily recovered by acid solution. This new technique for processing lepidolite could make most of all of its components, as well as being environmentally friendly.

Influence of mineral transformation on the reactivity evolution during rice straw char–NO reaction

Two kinds of chars were used in this research, the original rice straw char and the acid washed rice straw char. Their reactivity evolution during the char–NO reaction was studied in a fixed bed reactor at 900°C and 1000°C. The char samples obtained at different conversion were analyzed by BET and Inductively Coupled Plasma–Atomic Emission Spectrometry (ICP–AES). The reactivity of the acid washed char increased first and then decreased with the turning point at the char conversion of about 70% at both 900°C and 1000°C. This was consistent with the development of specific surface area. The reactivity evolution of the original char was similar as acid washed char at 900°C, but the reactivity decreased continually to zero at 1000°C, which contradicted the specific surface area development of original char. The measurements of mineral concentrations in char showed that K, Ca and Mg were the primary minerals in the original char. During the char–NO reaction, the transformation of K, Mg and Ca occurred, the concentrations of acid soluble K and Mg decreased 26.5% and 2.7% respectively, while the concentration of Ca increased 20.4% from char conversion Xchar=0% to Xchar=44.6% at 1000°C. The transformation of acid soluble K was consistent with the reactivity evolution of char during the char–NO reaction, which indicates that acid soluble K played an important role on char reactivity evolution during the char–NO reaction. The specific reactivity of char had a nearly linear relationship with the concentration of acid soluble potassium in char.

The use of chemical extractions and continuous cropping to measure the potassium status of soils

Soil potassium, measured by simple chemical extractions, was compared with potassium availability assessed during continuous cropping of perennial ryegrass in pots, on 12 surface soils representing four Tasmanian soil groups. For three soil groups with mainly kaolinitic clay, potassium uptake by the plant (the main measure of potassium availability) was related to a decrease in the potassium extracted from the soil by boiling lM nitric acid during the experiment. The decrease in soil potassium extracted by repeated nitric acid digestions averaged 95% of the total potassium uptake. However, a large and rapid uptake from the illitic yellow podzolics was only partly assessable by chemical extractions. For all soils, much of the large amount of potassium taken up early was stored in the plant roots and transferred to the tops much later. Plant yields were related to exchangeable potassium only within soil groups; over most soils they were related to nitric acid-soluble potassium. Yield responses to added potassium usually occurred when exchangeable potassium became depleted to a critical level of 0.2–0.25 m-equiv./100 g or nitric acid-soluble potassium to 0.4–0.7 m-equiv./100 g. The critical level of potassium in ryegrass tops was 0.5–0.8%. On average nearly two-thirds of the potassium released from soils came from exchangeable sources. Potassium initially non-exchangeable was differentiated into quickly released 'intermediate' potassium and slowly released 'constant rate' potassium. Release of intermediate potassium predominated from the yellow podzolics and from one non-calcic brown soil with much randomly interstratified material in its clay.

The presence of indigenous glauconite in soils and its effect on soil fertility:I. Soils developed on sandy drift (Barming series)

SUMMARYThe fertility, especially potassium status, of the Barming series in East Kent was studied by laboratory and pot test procedures to determine the effect of indigenous glauconite. Half of 12 otherwise similar soils contained appreciable glauconite.Glauconite contributed positively to the potassium status of the soils, especially the B horizons (45–65 cm), and was associated with higher values of exchangeable potassium, cation exchange capacity, nitric acid soluble potassium and intensity of potassium supply as measured by ΔḠ. More potassium was taken up and more released from initially non-exchangeable sources to ryegrass from the glauconitic soils. The available magnesium content of the soils was also positively correlated with glauconite content but available phosphate was not.

Release of nonexchangeable potassium from Finnish mineral soils

Release of nonexchangeable potassium by treatment with 1 N HCI at 50°C was studied on basis of a material consisting of 330 samples of Finnish mineral soils. The results ranged from 1 to 830mg K/100g. The mean content of nonexchangeable acid-soluble potassium was in the surface samples of sand and fine sand soils 95±26 mg/100 g, in loam soils 165±31 mg/100 g, in silt soils 195±52 mg/100 g, in clay loam soils 258±32 mg/100 g, in silty clay soils 283±43 mg/100 g, and in heavy clay soils 345±126 mg/100 g. In the subsoil samples of loam, clay loam, silty clay and heavy clay soils the mean content was significantly higher than in the surface samples, or 283±51 mg/100 g, 404±56 mg/100 g, 535±53 mg/100 g, and 580±37 mg/100 g, respectively. The results seem to be high as compared with data reported from Sweden, Norway and Germany. The content of nonexchangeable potassium released by acid was to some extent connected with the clay content: the correlation coefficient in the whole material was r = 0.74***, but only about 0.5*** both in the separate groups of the 178 nonclay samples and the 152 clay samples. There was only a very low correlation between the contents of nonexchangeable acid-soluble potassium and readily exchangeable potassium. A somewhat higher correlation, r = 0.65***, was found for the relationship between the former and fixation of added potassium under »wet» conditions, but it was markedly decreased by the elimination of the effect of the clay content. Nonexchangeable acid-soluble potassium usually represented a lower part of the total potassium in the surface samples than in the subsoil samples, and also the proportion tended to be higher in the clay soils than in the coarser soils. It varied from 0.2 to 26.3 per cent in the small material studied. In most cultivated soils less nonexchangeable potassium was released from the samples of plough layer than from samples of deeper layers. In a podsol profile the minimum content of nonexchangeable and exchangeable potassium and the maximum of fixation of added potassium was found in the A2 horizon; in a brown podsolic soil all these test values decreased fairly regularly with depth. From some silt and silty clay soils incubated for three months at room temperature a large part, even more than 40 per cent of the added potassium was not recovered by the acid extraction. Ammonium acetate extracted from 9 to 85 per cent of the potassium applied before incubation, and the part of added potassium found as nonexchangeable acid-soluble form varied from 5 to 53 per cent. The equilibrium between the different potassium fractions in soil was discussed. It was supposed that differences in the ability of plants to utilize nonexchangeable potassium may partly depend on the level to which plant roots are able to decrease potassium concentration in the solution around the minerals.

Effect of Long‐Term Fertilizer Application on Exchangeable and Acid Soluble Potassium1

AbstractThe movement of K within the soil profile of several Jordan Plot soils was studied. Samples from 6‐inch depth intervals (to 36 inches) from plots treated with excess lime, manure, and commercial fertilizer were analyzed for exchangeable and acid soluble K, and the data were compared with those from untreated plots of both limed and unlimed tiers.Long‐term applications (77 years) of manure and of commercial K fertilizer (KCl) significantly increased exchangeable K to depths of 12 and 24 inches, respectively. The same treatment significantly increased the amount of acid soluble K in the soil to depths of 6 and 12 inches, respectively. Neither exchangeable nor acid soluble K was influenced by excess lime treatments compared to the untreated plots.

The Characteristics of Tea Soils (Part 10)

Potassium supplying power of tea soils derived from volcanic ash soil, diluvial red-yellow and "Kuroboku" soil and tertiary yellow soil were examined by the extract method with N-nitric acid and 0.01 N-hydrochloric acid. Furthermore, potassium fixation power of those tea soils were examined by the VOLK'S method.The results were summarized as follows:1. Potassium supplying power of the four tea soils were pressumed as follows by the amounts of N-nitric acid soluble potassium of those tea soils, but that of diluvial "Kuroboku" soil did not show thee difinite tendency.Tertiary yellow soil>diluvial red-yellow soil>volcanic ash soil.Differences of potassium supplying power of soil between tea soil, cultivated soil and uncultivated soil were not abserved.2. From the characteristic potassium release curve of soil leached with 0.01 N-hydrochloric acid, potential potassium supplying power of those tea soils were abserved.Potential potassium supplying power of volcanic ash soil was the smallest and that of red-yellow and tertiary yellow soil was comparatively larger than the other soils. Furthermore, that of "Kuroboku" soil was larger than that of volcanic ash soil, but was presumed to be slightly smaller than that of red-yellow soil and tertiary yellow soil.3. Potassium fixation power of those tea soils was determined. It was observed that potassium fixation power of volcanic ash soil was generally small compared to the other soil and potassium fixation power of soil was not different among the other soils except volcanic ash soil.

Fixation of potassium by soil samples under various conditions

The fixation of added potassium under various conditions was studied using soil samples collected from three layers of ten mineral soils. The type of soil ranged from finesand to heavy clay, the soil reaction from pH 3.3 to pH 6.4 (in 0.01 M CaCl2), and the total potassium content from 1.99 to 3.41 per cent. The fixation against an extraction with neutral ammonium acetate distinctly depended on the conditions used for the application of potassium: on the average, without drying the samples fixed during one hour somewhat more than 80 per cent of the amount fixed during 18 hours, when the samples were treated with KCI-solutions corresponding to 2.5 me K/100 g soil. Drying the suspension at 80°C resulted in a fixation 1.2 to 4.1 times as high as that under the »wet» conditions within one hour. The results of these two methods were not particularly closely correlated (r = 0.73***). The results of the »dry» method were found to be of the same order as the fixation of potassium in samples incubated for three months at room temperature. The results of the »dry» fixation were positively correlated with the pH (r = 0.75***) and negatively correlated with the contents of organic carbon (r = —0.63***) and exchangeable potassium (r = —0.40*), but they were not correlated with the contents of clay or the acid soluble potassium. Under the »wet» conditions the relative fixation generally decreased with an increase in the application of potassium, but there were samples which fixed a rather low but almost equal portion of all the applications from 0.625 to 40 me K/100 g soil. The fixation from the highest addition was correlated with the clay fraction

THE EVALUATION OF THE RESIDUAL EFFECT OF FERTILIZER IN LONG-TERM FERTILITY PLOTS: I. POTASSIUM

Residual effects of long-term annual applications of fertilizer potassium on the potassium status of an acid sandy loam Podzol were investigated, in a greenhouse experiment. Potassium accumulated in the surface soil in a form readily available to plants.On plots with higher cation exchange capacities, resulting from manurial treatments, there was no evidence to indicate leaching below 15 inches. On plots where cation exchange capacity was not increased by treatment, a higher percentage potassium saturation at greater depths indicates that leaching of potassium had occurred to a depth of 21 inches. An increased concentration of nitric acid-soluble potassium at greater depths suggests that some of the leached potassium has been converted to the non-exchangeable form.Accumulation in the surface soil was sufficient to supply most of the potassium requirement of ladino clover under conditions of intensive cropping. The results suggest that exchangeable and nitric acid-soluble potassium are reliable criteria of available potassium.

Experiments with nitrogen and potash on barley

1. Four experiments in 1958 and five in 1959 compared responses to potassium (as combinedrilled muriate of potash) in the absence of nitrogen and in the presence of single and double doses of nitrogen (as broadcast sulphate of ammonia) on soils selected because they contained very little acid-soluble potassium.2. Responses to 0·5 cwt. K2O/acre were obtained at six centres (two significant), but the effects of a further 0·5 cwt. K2O/acre were more variable and gains and losses (each at four centres) were almost equally balanced.3. Gains from nitrogen were associated with previous cropping. N1 raised yields at seven centres (six significantly), but N2 raised yields further at only five centres (three significantly) and depressed yields significantly at three centres where barley followed a root crop or ley.4. Potash did little to improve the strength of straw and therefore standing capacity in a wet season (1958) and had little effect upon the size of the grain, whereas nitrogen increased lodging and reduced the average size of the grain.5. Increases in potassium uptake were associated with yield increases, whereas increases in nitrogen uptake were associated with both higher nitrogen percentage in grain and higher yields.

Influence of Continuous Cropping on the Fixation and Release of Potassium in Three Pennsylvania Soils

AbstractThe fixation and release of potassium by three Pennsylvania soils was studied under greenhouse conditions using ryegrass as the indicator crop. The soils studied were representative of the two types of clay mineral distributions determined by a previous mineralogical survey of the soils of Pennsylvania.The potassium fixed by the soils during the greenhouse experiment was measured two ways: the fixation of exchangeable potassium as nonexchangeable, and the fixation of acid soluble potassium as acid insoluble. The amounts of potassium fixed as nonexchangeable and as acid insoluble potassium were approximately the same. The potassium fixed under moist greenhouse conditions was less than that fixed by repeated wetting and drying the soils at 75°C. The difference in the potassium fixation capacities of the soils was related to the physical characteristics of the vermiculite contained in the respective soils.The release of potassium by the soils during the greenhouse experiment was again measured two ways: the release of acid insoluble potassium as acid soluble, and the release of acid soluble potassium as exchangeable. The best indicator of the rate of release of potassium was the acid soluble potassium. The different rates of release of potassium by the soils were related to the hydrous mica content and were responsible for the significant differences in the ryegrass yield of the three soils.

Acid‐Soluble Potassium and Microcline Content of the Silt Fractions of 12 Indiana Soils

Soil Science Society of America JournalVolume 16, Issue 4 p. 371-371 Note Acid-Soluble Potassium and Microcline Content of the Silt Fractions of 12 Indiana Soils† M. M. Phillipe, M. M. Phillipe Associate Agronomist Clemson Agricultural CollegeSearch for more papers by this authorJ. L. White, J. L. White Associate Professor of Agronomy Purdue UniversitySearch for more papers by this author M. M. Phillipe, M. M. Phillipe Associate Agronomist Clemson Agricultural CollegeSearch for more papers by this authorJ. L. White, J. L. White Associate Professor of Agronomy Purdue UniversitySearch for more papers by this author First published: 01 October 1952 https://doi.org/10.2136/sssaj1952.03615995001600040014xCitations: 4 †Journal Paper No. 569, Purdue University, Agricultural Experiment Station, Lafayette, Ind. Contribution from the Department of Agronomy. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume16, Issue4October 1952Pages 371-371 RelatedInformation

Exchangeable and Acid‐Soluble Potassium as Regards Availability and Reciprocal Relationships

Soil Science Society of America JournalVolume 10, Issue C p. 81-86 Article Exchangeable and Acid-Soluble Potassium as Regards Availability and Reciprocal Relationships† O. J. Attoe, O. J. AttoeSearch for more papers by this authorE. Truog, E. Truog Assistant Professor and Professor of Soils, respectively.Search for more papers by this author O. J. Attoe, O. J. AttoeSearch for more papers by this authorE. Truog, E. Truog Assistant Professor and Professor of Soils, respectively.Search for more papers by this author First published: 01 January 1946 https://doi.org/10.2136/sssaj1946.03615995001000C00013xCitations: 6 ‡ Contribution from the Department of Soils, University of Wisconsin, Madison, Wis. Publication approved by the Director of the Wisconsin Agricultural Experiment Station. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume10, IssueC1946Pages 81-86 RelatedInformation