Sulfated carbons

As opposed to the inorganic species presented above, there are a series of (often) biomass-derived sulfated materials that also display high levels of acidity. Again these are complex materials that have been partially characterised in terms of acid strength, partly because the commonly used Hammett indicator adsorption method cannot be used with black or strongly coloured materials. Here, there are different routes to their production that can be broadly divided into sulfonation/sulfation of preformed carbons and sulfuric acid-induced carbonisation/sulfation/sulfonation. 

Another study suggested the use of other sulfonating agents such as p-toluensulfonic acid (p-TSA). Although the material seems to be very efficient catal3ftically, its activity looks to be more related to the residues of p-TSA on the material than to attached sulfonic groups, because the analysis of the sample showed bands in the infrared spectra associated specifically to p-TSA. This would be likely to leach into solution. Another drawback of this approach is related to the manner of preparing p-TSA, as precursors involved will be toluene (petroleum base material) and sulfuric acid. 

1 Sulfonated Starbon , A Mesoporous Carbonaceous Solid Acid 

The majority of sulfonated carbonaceous materials are predominantly microporous, which limits their effectiveness for the transformation of all 

Since their discovery, the method of preparing Starbon has been very well explored and the resulting materials characterised. In this way, the elemental composition dependency on the carbonisation temperature was found, the starch-like systems found at low temperatures, the result of partial dehydration and polymerisation, switch to polyaromatic/graphitic-like at high temperatures of carbonisation.  

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Organic compounds containing sulfur are very important. Calcium sulfur, ammonium sulfate, carbon disulfide, sulfur dioxide, and hydrogen sulfide are but a few of the many important compounds of sulfur. 

Again, irrespective of the hardware the chemistry is consistent. The partially regenerated fiber from the spinning machine is contaminated with sulfuric acid, 2inc sulfate, sodium sulfate, carbon disulfide, and the numerous incompletely decomposed by-products of the xanthation reactions. The washing and drying systems must yield a pure cellulose fiber, suitably lubricated for the end use, and dried to a moisture level of around 10%. 

The carbonates, sulfates, nitrates, and haUdes of lead (except the yeUow iodide) are colodess. Bivalent lead forms a soluble nitrate, chlorate, and acetate a slightly soluble chloride and an insoluble sulfate, carbonate, chromate, phosphate, molybdate, and sulfide. Highly crystalline basic lead salts of both anhydrous and hydrated types are readily formed. Tetrabasic lead sulfate [52732-72-6] 4PbO PbSO, and the hydrated tribasic salt [12397-06-7] ... 

Great Salt Lake, Utah, is the largest terminal lake in the United States. From its brine, salt, elemental magnesium, magnesium chloride, sodium sulfate, and potassium sulfate ate produced. Other well-known terminal lakes ate Qinghai Lake in China, Tu2 Golu in Turkey, the Caspian Sea and Atal skoje in the states of the former Soviet Union, and Urmia in Iran. There ate thousands of small terminal lakes spread across most countries of the world. Most of these lakes contain sodium chloride, but many contain ions of magnesium, calcium, potassium, boron, lithium, sulfates, carbonates, and nitrates. 

Carbonates and Sulfates Carbonates include limestone, cal-cite, marble, marls, chalk, dolomite, and magnesite the most important sulfates are barite, celestite, anhydrite, and gypsum these are used as fillers in paint, paper, and rubber. (Gypsum and anhydrite are discussed below as part of the cement, lime, and gypsum industries.)... 

Lead and Alloys Chemical leads of 99.9+ percent purity are used primarily in the chemical industiy in environments that form thin, insoluble, and self-repairable protective films, for example, salts such as sulfates, carbonates, or phosphates. More soluble films such as nitrates, acetates, or chlorides offer little protection. 

Sr, and Ba sulfates, carbonates, and oxides Gunpowder erosion reducer. J.P. Picard,... 

When sulfates, carbonates, and other dissolved BW salts exceed their individual maximum solubility limits, they form sludges, scales, and deposits. This situation may arise either from a general overconcentration of the BW TDS (high COC) or from the deliberate precipitation of salts of selective ions, as occurs when using phosphate precipitation programs. 

After conversion to the use of sodium-based chemicals, spent liquor could be incinerated, and sulfur dioxide, sodium sulfate, carbonate, or sulfide could be recovered. These compounds could be sold for use at nearby kraft mills or for other industrial uses. 

E. Hayon and J. McGarvey, Flash photolysis in the vacuum ultraviolet region of sulfate, carbonate, and hydroxyl ions in aqueous solutions. J. Phys. Chem. 71, 1472-1477 (1967). 

The method is either not affected by or can allow for interference from phosphate, sulfate, carbonate, bicarbonate, nitrate, coloured metal complexes, ammonia dyes, detergents, phenols, and other ultraviolet-absorbing substances. The method incorporates three features designed to reduce interferences ... 

Hydrogen sulfates Carbonates, phosphates, chromates, silicates... 

If the pH is adjusted as part of an engineered remediation, the microbial balance may be upset and bioreactions slowed until the microbe cultures adjust to the new conditions. Alternatively, if the release of organic chemicals has altered the pH outside the natural range, it may be necessary to add certain chemicals (i.e., aluminum sulfate, carbon dioxide, sodium hydroxide, etc.) to return the pH to preexisting conditions. Changes of pH should be monitored since rapid changes of more than 1 to 2 pH units over a short period can inhibit microbial activity and may extend the acclimation period before the microbes adapt and renew activity. 

It is useful to know, that for a given type of crystals (oxides, sulfates, carbonates), the interfacial mineral-aqueous solution free energy, y (or ycw), increases with decreasing solubility (Schindler, 1967). Nielsen (1986) cites the following empirical relationship... 

The scaling tendency of the lime or limestone processes for flue gas desulfurization is highly dependent upon the supersaturation ratios of calcium sulfate and calcium sulfite, particularly calcium sulfate. The supersaturation ratios cannot be measured directly. They are determined by measuring experimentally the molalities of dissolved sulfur dioxide, sulfate, carbon dioxide, chloride, sodium and potassium, calcium, magnesium, and pH. Then by calculation, the appropriate activities are determined, and the supersaturation ratio is determined. Using the method outlined in Section IV, the concentrations of all ions and ion-pairs can be readily determined. The search variables are the molalities of bisulfite, bicarbonate, calcium, magnesium, and sulfate ions. The objective function is defined from the mass balance expressions for dissolved sulfur dioxide, sulfate, carbon dioxide, calcium, and magnesium. This equation is... 

Ammonium nitrate Ammonium sulfate Carbon black... 

Lanthanum oxide can be produced by direct combustion of lanthanum in oxygen or air. The oxide also may be prepared by decomposition of an oxo salt of lanthanum, such as nitrate, sulfate, carbonate, hydroxide or oxalate. 

Similar surfactants based upon glucopyranose were synthesized via the reaction of cyclic sulfate 65 with fatty acids or long-chain aliphatic amines, which proceeds regioselectively at the least hindered cyclic sulfate carbon, to give a range of methyl sulfoglucopyranosyl surfactants 66a-f (Equation 6, Table 2) <1999S621>. 

Sepiolite and palygorskite have a rather special composition and seem to be related to specific mineral parageneses. They appear to be stably associated with montmorillonite, corrensite, serpentine, chert, sulfates, carbonates and various salts. They are found in deposits typified by processes of chemical precipitation or solution-solid equilibria (Millot, 1964) and are therefore rarely associated in sediments with large quantities of detrital minerals. Their chemical environment of formation is in all evidence impoverished in alumina and divalent iron. Their frequent association with evaporites, carbonates and cherts indicate that they came from solutions with high chlorinity. 

In sulfation, substitution of polymeric chondroitin and chondroitin sulfates A and C by a hen-oviduct preparation has been described. The sulfate donor is adenylyl sulfate 3 -phosphate and a non-sulfated 2-acetamido-2-deoxy-D-galactosyl residue positioned internally in the polymer chain can be substituted.230 Evidence has been presented for another activity (from quail oviduct) that sulfates carbon atom 6 of a 2-acetamido-2-deoxy-D-galactosyl 4-C-sulfate group at the nonreducing end of the chain, giving the 4,6-di-C-sulfate.231... 

The simplest and most generally useful synthetic method for metal diketonates is from the diketone and a metal such as a halide, hydroxide, oxide, sulfate, carbonate, carboxylate, etc. in a variety of solvents such as water, alcohol, carbon tetrachloride or neat diketone. Since many / -diketones are poorly soluble in water, use of an organic solvent or cosolvent may be helpful. Optionally, a base such as sodium carbonate, triethylamine or urea may be added. Addition of a base early in the reaction converts the diketone to its conjugate base, which usually has greater solubility in aqueous media.159 In some cases, metal halide complexes of the diketone form as intermediates, e.g. SnCl4(MeCOCH2COMe), which has been formulated as... 

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