Charcoal, substitutes

Hints for Re-Cycling Waste. Under the form of charcoal and charcoal substitutes, combustible products from wastes can provide interesting commercial opportunities. 

Attapulgite Bismuth hydroxide Dextrin Kaolin Potassium hydroxide Silica gel Vermiculite absorbent charcoal substitute Fuller s earth absorbent, acid gases 2-Aminobutanol S (+) 2-Amino-1-butanol Aminoethyl propanediol Dimethylamine Methyidiethanolamine absorbent, acidic gases Aminomethyl propanediol Aminomethyl propanol 1,1-Dimethylhydrazine Tris (hydroxymethyl) aminomethane absorbent, ammonia Cobalt chloride (ous) Nickel chloride hexahydrate... 

Granular media filtration is used for treating aqueous waste streams. The filter media consists of a bed of granular particles (typically sand or sand with anthracite or coal). The anthracite has adsorptive characteristics and hence can be beneficial in removing some biological and chemical contaminants in the wastewater. This material may also be substituted for activated charcoal. 

Reduction of quinazoline oxides to quinazolines, catalytically (Raney nickel, palladium on charcoal) or with iron and ferrous sulfate in 85% alcohol can be extended to the preparation of benz-substituted quinazolines. ... 

Preparation of the substituted piperazine required for sul-falene (114) starts with bromination of 2-aminopiperazine to give the dihalide (150). Displacement of halogen by sodium methoxide proceeds regioselectively at the more reactive 3 position to give 151. Hydrogenolysis over palladium on charcoal gives the desired intermediate (152). 

Nitroindene Polymer (N.I.P.). Evaluated at PicArsn as a substitute for charcoal in fuze powders. The N.I.P. fuze powders gave longer burning times and lower dispersions in M54 Time Fuzes under rotation and reduced pressure than the corresponding charcoal powders. They were also more sensitive to impact Ref D. Hart, Investigation of the Use of Nitroindene Polymer in Powder for M54 Time Fuze , PATR 1296 (1943) PATR 1525 (1945)... 

Besides its usage in foods, indene polymer is used in the coatings industry, inks, floorings and in rubber applications. Some use has been made of the nitrated polymer as an ingredient in fuze powder (substituting for charcoal), but because of the sensy to impact this use is discontinued (Ref 3)... 

Paleine or Paleina. Dynamites patented by Langfrey in Engl in 1878 contg nitrated straw ( fulmi-paille ). One of the formulations could [G 35.0, Nitrostriv/ 18.6, ssltpstsr 32.5, sulfur 4.6, and potato starch 9.3%. Part of the sulfur could be replaced with hardwood charcoal, and dextrin could be substituted for the starch... 

Nursing alcohol lamps and charcoal fires in his tiny home laboratory during the Easter vacation of 1856, a teenager slowly teased out the constituents of a black and tarry goo. Working nights, weekends, and holidays on chemistry, he was searching for a test-tube substitute for quinine, the antimalaria drug derived from plants. The black precipitate he had made was obviously not quinine, but the youth was well trained in chemistry, so he did not throw it out. Instead, he treated it with alcohol, and a fabulously intense purple appeared. Then he tested the purple on a piece of silk. 

Electron-rich heterocyclic systems such as indolizines react readily with DEAZD (and PTAD) to give substitution products (Eq. 16).141 None of the formal [8 + 2] cycloaddition products (e.g., 89) are observed. This is in direct contrast to the reaction of indolizines with electrophilic acetylenes which gives high yields of cycloaddition products, presumably via a stepwise mechanism, in the presence of palladium on charcoal.142 This example of... 

Nielson125 reports the synthesis of 7-((V-aIkylamino)- and T-(N,N-di-alkylamino)-l,3,5-triazaadamantanes by reductive alkylation of 94, which is obtained from 91 by an improved hydrogenation procedure (rhodium-charcoal catalyst, 25.5 psi). Paper chromatography54 and the Kovats indices and relative elution volumes of 1,3,5-triazaadamantane derivatives are measured.55 7-Amino-l,3,5-triazaadamantane is used as a vulcanization accelerator.127 7-(N,N-Dialkylamino)-l,3,5-triazaadamantanes are utilized as a new class of high-density fuel (DIADAM).128 Some 7-substituted 1,3,5-triazaadamantanes have bacteriostatic and fungistatic activity.129 7-Bromo-,... 

An even simpler protocol for performing nucleophilic substitutions (aminations) and Suzuki reactions in one pot was reported by the Organ group for the generation of a 42-member library of styrene-based nicotinic acetylcholine receptor (nAChR) antagonists (Scheme 6.21) [49]. After considerable experimentation, the authors found that simultaneous nucleophilic displacement and Suzuki coupling could be carried out very effectively by charging the microwave process vessel with the palladium catalyst (0.5 mol% palladium-on-charcoal), the boronic acid [R1B(OH)2], the... 

Other markets for char include iron, steel, and sili-con/ferro-silicon industries. Char can be used as a reducing agent in direct reduction of iron. Ferro-silicon and metallurgical-grade silicon metal are produced carbothermally in electric furnaces. Silica is mixed with coke, either iron ore or scrap steel (in the case of ferro-silicon), and sawdust or charcoal in order to form a charge. The charge is then processed by the furnace to create the desired product. Char can be substituted for the coke as a source of reducing carbon for this process. Some plants in Norway are known to have used coal-char in the production of silicon-based metal products as late as mid-1990.5 The use of char in this industry is not practiced due to lack of char supply. 

The hydrogenation of 109 over palladium on charcoal in acidic methanol produced (l/ ,7aA)-l,3-diphenyl-5,6,7,7a-tetrahydro-1 //-pyrrolo[ 1,2-r]imidazolc 110 in 61% isolated yield (Equation 14). This reaction was totally unexpected and the authors proposed a mechanism that explains this transformation <2005JOC2368>. The mechanism is shown in Scheme 13. Many of the steps are interchangeable, but the end product is the same. The partial racemization observed could occur by epimerization of the phenyl-substituted carbon adjacent to the imine produced after the cleavage of the bicyclo-adduct. 

Oxazines are prone to hydrogenolysis since the relatively weak N-O bond is easily cleaved. This reaction has often been employed for the transformation of this cycle (generally obtained from nitrones) into amino alcohols in a stereocontrolled manner. For example, reaction of 57 with hydrogen and palladium on charcoal as catalyst (Equation 1) furnished the expected substituted pyrrolidine 58 in moderate yields <2003EJ01153>. 

The catalytic hydrogenation of A/-(2-substituted 2-phenyl-vinyl)-aminomethylenemalonates (1453) over 10% palladium-on-charcoal at 70°C in dioxane gave /V-(2-substituted 2-phenylethyI)aminomethyIenemaIo-nates (1454), while that of 1455 at 50°C afforded aminomethylmalonate (1456) (70AP612). The hydrogenation of 1456 under the previous conditions at 90°C yielded 1,3,5-trimethylbarbituric acid. 

The traditional use of phosgene in Scheme 4 can be avoided by substituting it with the less toxic triphosgene, which gives comparable yields of the M-car-boxyanhydrides. Diphosgene may also be used to form the NCA, but the reaction requires the use of charcoal and is not as reliable. Free amino acids have also been converted to their corresponding NCAs by the use of benzyl chloroforma-te with thionyl chloride. 

This method is very useful for the construction of 1-substituted 3,4-dihydroisoquinolines, which if necessary can be oxidized to isoquinolines. A P-phenylethylamine (l-amino-2-phenylethane) is the starting material, and this is usually preformed by reacting an aromatic aldehyde with nitromethane in the presence of sodium methoxide, and allowing the adduct to eliminate methanol and give a P-nitrostyrene (l-nitro-2-phenylethene) (Scheme 3.17). This product is then reduced to the p-phenylethylamine, commonly by the action of lithium aluminium hydride. Once prepared, the p-phenylethylamine is reacted with an acyl chloride and a base to give the corresponding amide (R = H) and then this is cyclized to a 3,4-dihydro-isoquinoline by treatment with either phosphorus pentoxide or phosphorus oxychloride (Scheme 3.18). Finally, aromatization is accomplished by heating the 3,4-dihydroisoquinoline over palladium on charcoal. 

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