Phosphate Of Lime Research Articles

Efficient flotation separation approach of apatite from calcite for phosphate up-grading using phosphorylated starch macromolecules as a selective depressant

Physico-chemical similarities of surface proprieties of calcite and apatite make their separation challenging. Effective flotation separation requires sustainable depressants to mitigate environmental consequences associated with traditional chemical reagents. Here, for the first time we explore the potential of phosphorylated starch (PS) derived from potato waste as a green and effective depressant. Starch was modified using a straightforward phosphorylation process, resulting in PS with a remarkable charge density exceeding 6000 mmol kg−1. The PS was then evaluated for its ability to depress apatite, enhancing the separation efficiency of apatite from calcite in phosphate rock beneficiation via reverse flotation. Micro-flotation experiments revealed PS's distinct depression effect on apatite while minimally impacting calcite. Floatability rates of apatite and calcite were 90.45 % and 92.68 %, respectively. Introducing 10 mg/g PS drastically reduced apatite recovery to <19 %, while calcite recovery remained at 78.80 %. The bench-scale flotation tests demonstrated an upgrading of the phosphate rock to 70,64 % Bone Phosphate of Lime (BPL) with a yield of 89,41 %. Mechanistic studies employing zeta potential (ZP), and wettability analysis elucidated the depression mechanism. Apatite retained hydrophilicity post-PS addition and conditioning with ester, while calcite-acquired hydrophobicity even in the presence of PS. Furthermore, PS exhibited substantial adsorption onto the apatite surface through chemical reactions involving the phosphate groups and the activated calcium sites on the apatite. Overall, PS stands out as a promising, eco-friendly, and remarkably efficient depressant for separating apatite from calcite through flotation.

Obtaining the partially acidulated phosphate rocks by means of intermediate-grade phosphate and diluted phosphoric acid: Influence of some parameters

Abstract In this work, some parameters during the partial acidulation by phosphoric acid of phosphate 53.75% BPL (bone phosphate of lime) having different particle sizes are determined. P2O5 recovery is obtained by performing a series of reactions using phosphoric acid diluted from 10 to 40 wt.% and with reaction times ranging from 10 to 50 minutes. The best conversion rates are obtained with the following reaction parameters: phosphates size: 88-177 μm, reaction time: 50 minutes and phosphoric acid concentration: 40 wt.%. In the second part, the water-soluble P2O5 of PAPRs (Partially Acidulated Phosphate Rocks) obtained with phosphoric acid 30% and 40 wt.% is measured. The results of experiments showed that the water-soluble P2O5 has reached 15.2% for PAPRs obtained by reacting phosphate 88 μm with phosphoric acid 40 wt%.

In Search of a Slingshot: Climate Action’s David and the Goliath of Deregulated Capitalism

In Search of a Slingshot:Climate Action’s David and the Goliath of Deregulated Capitalism Emily Walz (bio) Klein, Naomi. This Changes Everything: Capitalism vs. the Climate. New York, NY: Simon & Schuster, 2014. In the middle of the Pacific Ocean, the island of Nauru is a gutted shell, its interior rock, primarily phosphate of lime, long ago hauled away to be used as agricultural fertilizer in Australia and New Zealand. Financially and ecologically bankrupt, Nauru’s population has been reduced to living on an ever-shrinking strip of land. They are part of what author Naomi Klein calls the expanding “sacrifice zone,” those areas of the planet suffering the harshest development-related ecological degradation and the worst effects of climate change. Caught between the costs of rampant extractivism—the large-scale removal of minerals and raw materials from the earth, often for export—and a coming climate crisis, Nauru’s leaders have gone public, using their story as a cautionary tale so that other nations might act to avoid similar fates. Nauru is one of the cases in Klein’s 2014 book This Changes Everything: Capitalism vs. the Climate, a wide-ranging exploration of the intersection of climate science and the dynamics of the international political and economic systems that prevent climate issues from meriting top billing on the global political agenda. In Klein’s view, climate change is not just another issue; it is the issue to end all issues, with links to the anti-globalization and anti-corporation arguments at the center of her other books, The Shock Doctrine (2007) and No Logo (1999). Deregulated capitalism, as the world’s dominant economic system with its attendant demands for continual growth, is on a collision course with the finitelyresourced planet that houses it. Klein makes clear that only one of these factors can change: nature or the economic model; and it will not be nature. The litany of climate change casualties is familiar: rising sea levels, intensifying severe weather patterns, acidifying oceans, disruption to harvests and supply chains, and swells of climate migrants and refugees. Those who agree that danger [End Page 205] is imminent and that now is the time for action include more than scientists and small island nations; the International Energy Agency wrote in 2012, “the climate goal of limiting warming to 2°C is becoming more difficult and more costly with each year that passes.”1 The World Bank too has sounded alarms, warning that there is “no certainty that adaptation to a 4°C world is possible.”2 Even Catholic bishops have called for halts at 1.5°C—a more progressive emissions target than negotiators within the international system have ever incorporated into proposals for ratification by member states.3 Meanwhile, the fossil fuel industry is working to bring extraction to new extremes, pulling crude bitumen from Alberta’s Athabasca oil sands and suing to overturn local bans on hydraulic fracturing. The major energy companies already hold enough conventional fossil fuel in reserves to far exceed estimates of the planet’s atmospheric capacity to absorb carbon, meaning that the addition of these new, unconventional methods for obtaining further supplies—which extrexact a higher environmental cost in extraction than their conventional counterparts—may push potential carbon consumption far beyond pivotal thresholds. The irreconcilability of the shrinking emissions needed to avoid disastrous climate consequences with these growing pools of exploitable fossil fuels is exacerbated by an economic system not built to take environmental externalities into account and incapable of holding polluters fully accountable. Separate from fossil fuel sector interests, Klein cites whole industries of “disaster capitalists” preparing to seize profit opportunities. Disaster insurers, climate futures traders, weapons manufacturers, security corporations, upscale disaster-ready housing construction firms, and multinational agrochemical and biotechnology companies preparing “climate-ready” seed varietals are among those poised to benefit from climate change-related dramatic environmental events. The dismal picture Klein paints is enough for overload; even she admits to having indulged the impulse to look away when faced with evidence of the gravity of the situation. But in This Changes Everything, Klein confronts these issues head on, grappling with the question “What is really preventing us from putting out the fire...

Investigation of jigging as a method for removing dolomite from high-MgO phosphate ores

Dolomite [CaMg(CO3)2] is an intolerable impurity in phosphate ores, due to its MgO content. The need to develop a cost-effective method for the removal of dolomite from high-MgO phosphate ores becomes increasingly important as high-grade reserves become depleted. The jigging process has been investigated as a method for the beneficiation of phosphate ores. A laboratory-scale jig was constructed and tested using a semicontinuous, “through-the-screen” jigging process. Two types of sedimentary phosphate ore were used; a sample from Plant 1 in the 4.00 × 0.85-mm size range, containing 1.55% MgO, and a sample from Plant 2 in the 3.40 × 0.85-mm size range, containing 3.07% MgO. These were tested, using previously optimized jigging parameters, at high and low feed rates. For the Plant 1 phosphate ore, a phosphate concentrate that contained 0.89% MgO was achieved with a bone phosphate of lime (BPL) recovery of 32.0%. For the Plant 2 phosphate ore, a phosphate concentrate that contained 1.38% MgO was achieved, with a BPL recovery of 74.7%. Minimum achievable MgO grades were also determined by analyzing hand-separated phosphate samples.

On the adulteration of bread as a cause of rickets. 1857.

On the adulteration of bread as a cause of rickets. 1857.

Separation of Valuable Fine Phosphate Particles from Their Slimes by Column Flotation

Large quantities of fines are generated as slimes during beneficiation of phosphate ores. These slimes are discarded due to the lack of a suitable method for their treatment. This decreases the total recovery of phosphate. Moreover, the presence of these slimes causes an environmental problem in some localities. This paper studies the possibility of recovering the valuable fine phosphate particles (45 μm) from their slimes through the application of the column flotation technique. Tests were performed using oleic acid as a collector for the phosphate minerals, and sodium silicate as a depressant for their associated gangues. The main operating parameters affecting the performance of column flotation were investigated. The results indicate that the best operating conditions for column flotation of phosphate slimes are: superficial gas velocity 0.84 cm/s, frother concentration 0.1 kg/ton, column height 230.5 cm, and superficial water velocity 2.2 cm/s. At these conditions a product assaying 25.3% P2O5 (∼55.24% BPL, bone phosphate of lime) and 14.64% I.R. (insoluble residue) with a P2O5 recovery of about 51.52% was obtained from a feed containing 18.26% P2O5 (∼39.87% BPL) and 24.03% I.R. Such a grade and recovery were not obtained by applying the conventional froth flotation technique, even after cleaning the rougher concentrate. Recovery of more than 50% of phosphate from disposed slimes will improve the economic viability of the beneficiation process for phosphate ores. It will also help in solving the environmental problems associated with the disposal of these slimes.

TVA pilot-plant phosphate flotation conditioning study

TVA conducted an extensive test program in its 1,000-pound-per-hour phosphate beneficiation pilot plant to study the effects of major variables in the conditioning step prior to phosphate flotation. Florida rock fine flotation feeds of 14 and 18 bone phosphate of lime (BPL) from the Bone Valley formation were tested. During Phase I for each flotation feed, a full factorial design was used for the test series to evaluate the effects of agitation, retention time, and solids content on P2O5 recovery and product grade. In Phase II, a qualitative test study was completed of several additional variables including agitator flow direction, slurry feed position, use of baffles or no baffles, fuel oil to fatty acid ratio, and reagent dosage. The results of both test series were statistically analyzed and compared with those obtained from batch, laboratory-scale flotation tests of pilot plant conditioned samples. From the pilot-scale results, a mathematical model was developed relating product grade and P2O5 recovery to the major process variables.

Rapid analysis of Florida phosphates by energy-dispersive X-ray fluorescence

A rapid X-ray fluorescence technique has been developed to determine the BPL (Ca 3(PO 4) 2 or Bone Phosphate of Lime) content of various streams in Florida phosphate beneficiation and in supporting laboratory flotation experiments. The method, which requires simple sample preparation, a 100-sec counting, and has an accuracy of better than 2% BPL (0.4% P), employs an Fe 55 radioactive source and a room temperature detector to analyze for calcium. The BPL values, which can not be obtained readily and directly because of the weak fluorescence of phosphorus, are instead derived from a close correlation found to exist between the phosphorus and calcium concentrations.

津市米津地区の異常酸性養鰻池の改良に対する施肥の効果

Acid eel-culture ponds with pH lower than 5 are very rare, but the authors favourably found one of such a kind of pond near the seashore in the southern vicinity of Tsu City, Mie prefecture, Middle Japan. It hasα-mesohaline brackishwater and the pH-value of 4.2, (area 25 a, depth 90 cm, Cl 2.12.4‰). Its acidity is possibly due to sulphuric acid which was derived from sulphide in the bottom mud.1) The biological and chemical features of the acid eel-culture pondThe pond-water is of the pH4.24.6. Although a green alga Chlamydomonas acidophila enormously increased, the transparency about 30 cm, and the oxygen dissolved in the water was not so rich (4.5 cc/L, 61%). The diurnal changes of dissolved oxygen and pH are extremely slight ; and are rich in both NH4- and NO3N, but a little in PO4-P. The plankton is quite monotonous, being composed of Chlamydomonas acidophila and an oligochaeta, Nais pardalis, though their quantities are large. The fry of Mugil cephalus L. transplanted there from the sea were killed entirely. No feeding activity of eels in culture was observed at all.2) The effect of limingTo neutralize the acid pond-water, 160kg of lime in total were sprinkled there on April 19th, 20th, and 23rd. After this operation, the feeding activity of eels became remarkably buoyant, but the green alga Chlamydomonas acidophila, as it was expected, suddenly diminished and the transparency accordingly rose, while the dissolved oxygen decreased. It is worthy of notice that an aquatic plant Potamogeton pectinalis began to grow over the bottom of the pond. Then the feeding activity of eels became dull day by day.3) The effect of fertilizationTo increase the phytoplankton and to control Potamogeton in the pond, fertilization was planned. It was carried out three times according to the following program : 1st fertilization May 17 phosphate of lime 14 kg2nd fertilization May 22 phosphate of lime 28 kg dry poultry manure 150 kg3rd fertilization July 16 phosphate of lime 35 kg urea 34 kgThe effects of the first and the second fertilization were not satisfactory, Potamogeton grow thicker, no “water-bloom” being observed (Figs.13). However, the third fertilization was quite effective after Potamogeton was removed as much as possible (Figs.13); a striking “water-bloom” occurred and the feeding activity of eels was rapidly improved. The quality of the pond-water, the zooplankton and phytoplankton have been restored as in a pond of normal conditions. Thus, the acid pond has been almost perfectly improved through the liming and three times of fertilization.

Calcium Carbide and the Board of Trade

PROF. SODDY is a trifle impetuous: my reference to Hazlitt was not out of place, it seems. If I follow my critic, as only a small heap of solid phosphate of lime will be left of me when I am burnt, I am not organic. Granted that calcium acetylide (carbide) gives lime when wetted, it is a little surprising that the putative father of Emanation and the first to make clear the significance of helium should attach no importance to the escaping gas. If a man have a wooden leg, he is none the less counted a man, I believe. Now, when zinc ethide is started swimming in water, it leaves behind it its leg, as it were, in the form of zinc oxide, just as carbide does, though in the form of lime; yet the ethide ranks as one of the most honourable of synthetic organic chemicals: why discard the carbide?

Gold-coloured Teeth of Sheep

IN NATURE of June 9 last (p. 459), recently arrived here, is a communication from Mr. W. J. Lewis Abbott concerning the metallic-looking encrustation occurring on the teeth of sheep. In Proc. Linnean Soc. N.S. Wales (vol. 45, 1920, p. 324), abstracted in NATURE of April 21 last (p. 249) and reprinted in full In the Chemical News (vol. 122, p. 49), I give a detailed report, with analyses, of this and similar deposits on the teeth of a number of other animals, including man. In no case is the deposit of a metallic nature, but consists entirely of a salivary encrustation composed usually mainly of phosphate of lime with organic matter. The metallic appearance is an optical effect due to the refraction of light by the overlapping thin lammellæ of the deposit.

The solubility of calcium phosphates in citric acid

The results of these investigations show1. The substances sold as “Phosphate of lime” and “Calcium Phosphas B.P.” are not pure tricalcic phosphate but are mixtures of di- and tricalcic phosphates.2. Sodium phosphate (Na2HPO4) added to ammoniacal calcium chloride and the resulting precipitate washed with water yields a mixture of di- and tricalcic phosphate and calcium hydrate.3. Bone ash dissolved in hydrochloric acid and precipitated with ammonia, the precipitate being well washed, yields also a mixture of di- and tricalcium phosphate and calcium hydrate.4. When three equivalents of lime (3CaO) are made to act on one equivalent of phosphoric acid (P2O5) and the resulting precipitate removed with little delay pure tricalcium phosphate is obtained.

On Fermorite, a new arsenate and Phosphate of lime and strontia, and Tilasite, from the manganese-ore deposits of India

Analyses of Indian manganese-ores generally show the presence of small amounts of arsenic. The form in which this constituent occurs was discovered by Dr. L. Leigh Fermor in the course of his investigations of these well-known deposits. At two different localities crystalline arsenates were found. One of these occurrences is at the Sitapar deposit in the Chhindwara district, Central Provinces. The pinkish-white to white arsenate found there is the new mineral to which we have given the name fermorite. The other locality at which an arsenate was found is Kajlidongri, Jhabua State, Central India. The pale-green arsenate, somewhat resembling apatite in appearance, which occurs at this locality has been found by us to be identical with the tilasite from Sweden described by Sjögren.

A Description of Christmas Island (Indian Ocean): Discussion

Tish Cove with his family and a few men from Cocos. During his stay some substantial houses have been built, wells sunk, and fruit-trees and coconut palms planted, and a small experimental plantation of -coffee was also made, and the results leave no doubt that the island is well suited for coffee-growing. Recently a number of coolies have been imported from Java to make the necessary preparations for working the valuable deposits of phosphate of lime. When I left the island in May, 1898, the total population was about forty. Finally, I must express my deep obligation to Sir John Murray, who rendered my visit to the island possible. My thanks are also due to Messrs. G. and A. Clunies-Ross for their hospitality and assistance while I was on the island; and to their nephew, Hugh Ross, who accompanied me everywhere on my various expeditions, and whose knowledge of bush life was of the greatest value to me.

LITHOLAPAXY; SUCCESSFUL REMOVAL, FROM THE BLADDER OF A MAN 30 YEARS OLD, OF A WILLOW TWIG 7 INCHES LONG, WITH HEAVY INCRUSTATION OF CALCIUM PHOSPHATE.

In the month of September, 1895, I was called in consultation in Johnstown by Dr. A. N. Wakefield and Dr. F. Shill, to see a man about 30 years of age, who stated that he had gravel. The man showed us a small piece of willow twig, half an inch long and about the thickness of an ordinary match, incrusted for half its length with phosphate of lime making the mass one-quarter of an inch in diameter. He had passed this piece of twig from his bladder within a week, also two smaller pieces during the month of January last. He said that in November, 1895, he had shoved up in his urethra a long piece of willow twig and that it had accidently broken off at the head of his penis. As is usually the case with foreign bodies in the urethra, this willow twig had been carried by

III.—On the Existence of Rich Phosphate of Lime in the London Basin

The proof which I gave in June, 1891, of the production of “rich phosphate” by enrichment of phosphatic chalk through the influence of the Tertiary deposit called “bief,” enabled us to foresee the existence of similar rich phosphate in the London Basin; since phosphatic chalk, analogous to that which I had described or discovered in Picardy, especially at Hardivilliers and Hallencourt, had been discovered by Mr. Strahan and described by him in an interesting paper “On a Phosphatic Chalk with Belemnitella quadrata.”

Societies and Academies

PARIS.Academy of Sciences, August 3.—M. A. Chatin in the chair.—Study of the diamond-bearing sands of Brazil, by M. H. Moissan. From 4˙5 kilos, of sand, only 2 gr. of material free from silica was obtained, and this was found to contain a small quantity of gold, platinum and graphite, together with a minute amount of diamond, partly black and partly transparent.—On the oxidation of the organic material of the soil, by MM. P. P. Dehérain and E. Demoussy. At temperatures slightly above 100° the organic material of soil is rapidly burnt by the oxygen of the air. This oxidation still goes on, without any organisms being present, at 40° to 60° C., and hence in hot climates the soil would become sterile from this cause.—On a hybrid from Ovis tragelaphus, by M. A. Milne-Edwards.—An extension of the application of the law of equivalence of energy in biology, by M. A. Chauveau.—Remarks on a note of M. A. Lœwy on definite quadratic forms, by M. L. Fuchs. The theorem in question is a special case of a theorem given in a memoir published in the Sitzungsberichte of the Berlin Academy.—The conditions under which the deposits of phosphate of lime have taken place in Picardy, by M. Gosselet. It is regarded as established that these phosphatic deposits were formed at very slight depths.—On the integration of simultaneous partial differential equations, by M. E. von Weber.—On a class of isothermal surfaces depending on two arbitrary functions, by M. A. Thybaut.—On the error of refraction in geometric levelling, by M. Ch. Lallemand. The formulæ given in a preceding paper are for practical purposes given in a graphical form.—On the non-refractibility of the X-rays by potassium, by M. F. Beaulard. A prism of potassium gave no appreciable deviation of Röntgen rays, the index of refraction differing from unity by a quantity less than 1/10,000.—Nitrogen and argon in fire-damp and in gas from Rochebelle, by M. Th. Schlœsing, jun. The gas left after removal of methane and carbon dioxide, consisting of argon and nitrogen, on absorbing the latter gave amounts of argon varying from 1˙09 per cent. to 3˙27 per cent, of the mixture. These figures show that this argon does not come directly from the air, but it is still possible that it may have come indirectly by solution in water, in which argon is the more soluble.—On the specific heat of sulphur in the viscous state, by M. J. Dussy. The specific heat of viscous sulphur is distinctly higher in the viscous than in the liquid state. If the total quantity of heat lost by 1 gr. of sulphur in passing from a temperature T to 0° C. is plotted against the temperature, there is a distinct change of curvature at about 230° C.—Contributions to the analytical characters of the compounds of tungsten, by M. E. Defacoz. The tungsten compound is converted into a tungstate, heated with some KHSO4 and a little sulphuric acid, and a drop of this, added to such reagents as phenol, naphthol, morphine, &c., when characteristic colour reactions occur. Of these the red coloration with phenol, and the violet with hydro-quinol, are the most sensitive and distinctive.-On the action of aluminium chloride upon benzene containing thiophene, by M. Eyvind Boedtker. Hydrogen sulphide is evolved, and the bulk of the thiophene is destroyed.-On some new mixed tri-methylene compounds, by M. L. Henry. The new substances described are a-iodo-ai-chloro-propane, CH2C1. CH2.CH2I; and the corresponding nitro-derivative, CH2C1-CH2.CH2. (NO2).-The rapid estimation of the constituents of a mixture of primary, secondary, and tertiary amines, having the same fatty alkyl group, by M. Ch. Gassmann. The mixture is titrated with hydrochloric acid, and then with sodium nitrite in acid solution; the solution of the resulting simultaneous equations gives results of sufficient accuracy for industrial purposes.-On the compounds oxidisable under the influence of the oxidising ferment of mushrooms, by M. Em. Bourquelot. -On the hyber-nation of the Clavelina lepadiformis (Miiller), by MM. A. Giard and M. Caullery.-Treatment of experimental infections by intravenous injection of a solution of common salt (07 per cent.), and their mode of action, by MM. F. J. Bosc and V. Vedel.-On the nature of the "Chabins,"by M. Ch. Cornevin. The Chabin (so-called by Gay) of Chili is not a hybrid, but a species of sheep.-Chemical study of low-class flour used in baking, by M. Balland.-On the proximate composition of the gluten of cereals, by M. E. Fleurent.

Microzoa from the Phosphatic Chalk of Taplow

The present paper is the result of an examination of some material kindly sent me by Mr. Llewellyn Treacher, who obtained it from about the middle of the phosphatic band at Taplow. A short list of the foraminifera of the Taplow Chalk has already been given by A. Strahan, Esq., M.A., F.G.S., of H.M. Geological Survey, with the assistance of Prof. T. Rupert Jones, F.R.S., F.G.S., and I wish at this point to express my obligation to the latter for help and advice in preparing these notes. The material used was excessively rich in well-preserved specimens of foraminifera, forming perhaps 75 per cent. of the whole; and a series selected from it proving so extensive and interesting, there seemed good cause to communicate a list of them. On treating the disintegrated chalk with a weak solution of hydrochloric acid, the most perfect casts in phosphate of lime are obtained, the Rotaline forms being especially noteworthy. The total number of species and varieties of foraminifera found is 98; and to these must be added 5 species and varieties of ostracoda, represented by 11 specimens. All the forms of ostracoda herein noted have been previously found in the Chalk. They are:— Pontocypris triquetra , Jones, sp., 2 specimens; Bythocypris silicula , Jones, sp., 1 specimen; Cythereis auriculata , Cornuel, sp., 1 specimen; C. Wrightii , Jones and Hinde, 6 specimens; and Cytherella Williamsoniana , var. granulosa , Jones, 1 specimen. Of the 98 varieties of foraminifera, 5 appear to be entirely new to science, whilst altogether 30 are new

Nature and Origin of Phosphate of Lime

Nature and Origin of Phosphate of Lime

On the Upper Cretaceous Series and the Phosphatic Beds in the Neighbourhood of Mons (Belgium)

The increasing importance of the use of phosphate of lime in agriculture induces me to give to English geologists some account of the beds that have been worked in Belgium during the last few years. The phosphatic beds of which I wish to speak are situated in the province of Hainaut, near to the town of Mons, on the lands of the Communes of Cuesmes, Ciply, Mesvin, Nouvelles, Spiennes, Saint Symphorien, and Havré. This part of Belgium is traversed by numerous railways and by a canal which enables boats of from 200 to 300 tons to penetrate to the centre of France, and to reach the ports of Ghent, Ostend, Antwerp, Dunkirk, &amp;c. The working of the phosphate of lime began in 1870, and its production, small at first, was not developed until 1877. The following figures will show its increase from that date :— A large portion of this mass was sold in Great Britain and Ireland, about 35,000 tons having been sent there in 1883. It is probable that the annual yield will soon exceed 100,000 tons; but the description which I am about to give will show that a much higher figure may be reached. Our beds of phosphate of lime occur in the Upper Cretaceous series, the thickness and variety of the strata which constitute it attaining greater importance in the neighbourhood of Mons than in any other part of Western Europe. The Cretaceous series of the province of Hainaut belongs to the great Anglo-French geological