Treatment Of Methanol Research Articles

Biodiesel fuel from rapeseed oil as prepared in supercritical methanol

Transesterification reaction of rapeseed oil in supercritical methanol was investigated without using any catalyst. An experiment has been carried out in the batch-type reaction vessel preheated at 350 and 400°C and at a pressure of 45–65 MPa, and with a molar ratio of 1:42 of the rapeseed oil to methanol. It was consequently demonstrated that, in a preheating temperature of 350°C, 240 s of supercritical treatment of methanol was sufficient to convert the rapeseed oil to methyl esters and that, although the prepared methyl esters were basically the same as those of the common method with a basic catalyst, the yield of methyl esters by the former was found to be higher than that by the latter. In addition, it was found that this new supercritical methanol process requires the shorter reaction time and simpler purification procedure because of the unused catalyst.

Treatment of methanol in a dry biofilm reactor using tubular carrier

A 13.4 l Dry Tubular Biofilm reactor (DTB), with 19 PVC tubes as carrier, was used to treat polluted air using methanol as a model pollutant. The design of this reactor was based on the creation of a mist by contacting the waste gas and a discontinuous liquid nutrient supply into an atomising nozzle. Air was fed into the reactor at specific gas flow rates from 60 to 230 m3/m3 · h, containing from 0.25 to 2.84×10-3 kg/m3 of methanol (volumetric loading rates from 1.4 to 4.7 kg/m3 · d). Biofilm growth was observed from the very beginning of the experiment although preferentially on the reactor's wall and not on the tubular carrier. Methanol degradation was observed to increase along the experiment and reached 1.24 kg/m3 · d. The efficiency of this system was limited by the clogging of the tubes used as carrier. The biofilm developed directly on the wall of the reactor had a specific methanol degradation rate of 1.08 kg/kgVSS · h, while only 0.6 kg/kgVSS · h of methanol were degraded after a long lag phase by the biomass developed inside the tubular carrier. Another experiment was carried out with the empty reactor without PVC tubing. In that case, a specific degradation rate of 4.15 kg/m3 · d was observed, which confirm that PVC tubular carrier was clearly not favourable to the process.

Genesis of V4+ in heteropoly compounds CsxH4-xPVMo11O40 during thermal treatment, rehydration and oxidation of methanol studied by EPR spectroscopy

The development and structural changes of V4+ and Mo5+ centers in caesium salts and the acid form of molybdovanadophosphorus heteropoly compounds CsxH4−xPVMo11O40 ·nH2O (x=0, 3, 4) of Keggin structure were investigated by electron paramagnetic resonance (EPR) after preparation, thermal treatment in oxygen, reduction by methanol and catalytic oxidation of methanol. The various types of paramagnetic centers are found to characterize the different states and structural transitions of the heteropoly anion. In addition, the EPR spectra reflect well the different reducibility, thermal stability and mobility of vanadium and Keggin (“ lattice”) oxygen of the Cs4, the Cs3H and the H4 compounds. The V4+ centers in the Cs4 salt are different in structure, lower in concentration and thermally more stable than those in the acid form. The reduction of vanadium during thermal treatment due to the loss and oxidation of coordinated (“ lattice”) oxygen to O2 is observed in the acid and the Cs3H salt only, but not in the Cs4 compound. As deduced from quantitative EPR measurements and manganometric redox titrations, between 0.5 and 8% of the vanadium is present as V4+ after preparation and thermal treatment in oxygen, whereas the majority of vanadium is reduced by reaction with methanol. V4+ substitutes Mo atoms in the Keggin unit in the fully exchanged Cs salt (Cs4). The presence of the bulky caesium counter-cations prevents the removal of vanadium from the Keggin unit to the secondary structure and thus the formation of vanadyl bridged polymers.

Biodiesel Fuel from Vegetable Oil Wastes by Supercritical Methanol.

The transesterification reaction of rapeseed oil in supercritical methanol was investigated in this study, without using any catalyst. It was consequently demonstrated that, in a preheating temperature of 350°C, 240 sec of supercritical treatment of methanol was sufficient to convert rapeseed oil to methyl esters with the molar ratio of methanol in triglycerides being 42. In addition, although prepared methyl esters were basically the same as those of the common method with a basic catalyst, the yield of methyl esters by the former was found to be higher than that by the latter due to a successful methyl esterification of free fatty acids present in the rapeseed oil. Furthermore, the kinetics study showed that the conversion rate of rapeseed oil to its methyl esters was found to increase dramatically in the supercritical state. Therefore, supercritical methanol process which requires the shorter reaction time and simpler purification procedure because of the catalyst unused, would become a powerful method for recycling vegetable oil wastes to biodiesel fuel.

Electrochemical synthesis of free-standing polyacetylene film with copper catalyst

Acetylene was potentiostatically electropolymerized in the presence of a Cu-TMEDA catalyst in DMF containing LiClO4 under an argon atmosphere, affording a black filmy product deposited on a Pt cathode. The product was liberated as a free-standing film by a treatment of methanol. The film was found to consist of amorphous trans-rich polyacetylene chains whose degree of polymerization was more than 50 with contaminants such as metals and the electrolyte. SEM analysis of the film surface showed a cauliflower-like morphology without fibliler structures. Electrical conductivity of the film was about 10 S cm−1 upon I2 doping

Treatment of Methanol Poisoning With Intravenous 4-Methylpyrazole

Treatment of human methanol poisoning with the alcohol dehydrogenase inhibitor, 4-methylpyrazole (fomepizole), has not been previously described. We report the clinical and toxicokinetic data of a patient with methanol poisoning who was treated with fomepizole. Formic acid levels remained undetectable during fomepizole treatment, the toxic effects of methanol were prevented, and the patient made a full recovery. [Burns MJ, Graudins A, Aaron CK, McMartin K, Brent J: Treatment of methanol poisoning with intravenous 4-methylpyrazole. Ann Emerg Med December 1997;30:829-832.]

Treatment of mixed methanol and isopropanol poisoning with intravenous 4-methylpyrazole

Treatment of mixed methanol and isopropanol poisoning with intravenous 4-methylpyrazole

Treatment of mixed methanol and isopropanol poisoning with intravenous 4-methylpyrazole

Treatment of mixed methanol and isopropanol poisoning with intravenous 4-methylpyrazole

Investigation of biological reactor designs for treatment of methanol and thiodiglycol waste streams

Biological reactor designs for the degradation of the toxic compounds methanol and thiodiglycol are compared to determine the smallest volume. Both compounds exhibit substrate-inhibited cell growth behavior. Design equations were used to simulate a continuous stirred tank with cell recycle, continuous stirred tanks in series, and an optimized repeated fed-batch reactor. Thiodiglycol is the primary hydrolysis product of sulfur mustard (2,2′-dichlorodiethyl sulfide), commonly referred to as “mustard gas.≓ Experimental data for the growth ofAlcaligenes xylosoxidans xylososxidans (SH42) on thiodiglycol was fit by an Andrews type inhibition equation, while the data and model for the growth of methanol was taken from the literature. The simulation results indicate that the repeated fed-batch reactor leads to significant volume reduction compared to the other two reactors configurations.

Effects of 4-methylpyrazole, methanol/ethylene glycol antidote, in healthy humans

4-Methylpyrazole (4-MP), an inhibitor of alcohol dehydrogenase, may be useful for the treatment of methanol and ethylene glycol intoxications. A placebo-controlled, double blind, multiple dose, sequential, ascending-dose study has been performed to determine the tolerance of 4-MP in healthy volunteers. Oral loading doses of 4-MP were followed by supplemental doses every 12 h through 5 days, producing plasma levels in the therapeutic range. A slight, transient elevation in one or both serum transaminase values was observed in 6 of the 15 subjects treated with 4-MP. This effect was not dose related nor apparently mediated through a hypersensitivity reaction. Serum triglyceride levels were increased in 30% of 4-MP treated subjects, but also in 25% of the placebo subjects. 4-MP treatment did not produce any other significant changes in objective clinical parameters nor in subjective side effects. The results suggest that a mild, transient increase in liver function tests might be observed in some subjects treated with multiple doses of 4-MP. Nevertheless, the slower elimination rate and lesser degree of toxicity of 4-MP would make it preferable to ethanol in therapy of these poisonings.

Fine structure and oxygen permeability of silk fibroin membrane treated with methanol

Dissolved oxygen permeability, water content, crystalline structure, crystallinity, and density of silk fibroin membrane were measured as a function of immersion time of the membrane in 50 vol% aqueous methanol solution. Permeability coefficient and water content exhibited a minimum at the treatment time of 30 min. After the treatment of methanol the silk II crystalline structure appeared in the membrane. The density of the membrane decreased with increasing treatment time, although the crystallization proceeded in the membrane. These results indicate an existence of roughly molecular-packed space (void) among the crystals. The appearance of the minimum for water content was attributed to the development of the crystal and to the growth of the roughly molecular-packed space. In addition to these two effects, the chain immobilization effect associated with the crystallization was taken into account to explain the minimum for the permeability coefficient.

Synthetic studies on carbapenem and penem antibiotics(VI) improved synthesis of (3S,4S)-4-acetoxy-3-phenylacetamido-azetidin-2-one

Penicillin G potassium salt was transformed in high yield to 4-acetoxy-3-phenylacetaminoazetidinone by treatment of mercury acetate, ozonolysis and methanol in sequence.

Diagnosis and treatment of methanol and ethylene glycol poisoning

Diagnosis and treatment of methanol and ethylene glycol poisoning

The synthesis of NR4[(Ta6Cl12)(H2O)6]X4(R = Me or Et, X = Cl or Br) by the spontaneous reduction of [Ta6Cl12]4+to [Ta6Cl12]3+in acidic media: X-ray structure analysis of NMe4[(Ta6Cl12)(H2O)6]Br4

The treatment of an air-oxidized alkaline methanol–water or aqueous solution of [Ta6Cl12]4+ with concentrated hydrochloric or hydrobromic acid results in spontaneous reduction to [Ta6Cl12]3+; oxidation of some cluster units to hydrated tantalum(V) oxide occurs simultaneously. The isomorphous, paramagnetic series of clusters, NR4[(Ta6Cl12)(H2O)6]X4(R = Me or Et, X = Cl or Br) has been prepared. Aspects of the reduction of the [Ta6Cl12]4+ unit in acidic media are discussed. The crystal structure of NMe4[(Ta6Cl12)(H2O)6] Br4 has been determined by X-ray structure analysis. The compound crystallizes in the cubic space group Fd3m, with a= 19.926(5)Å and Z= 8. The structure has been determined by Patterson and Fourier methods and refined by full-matrix least squares to R= 0.042. It comprises [(Ta6Cl12)(H2O)6]3+ octahedra connected by O–H …Br hydrogen bonds, NMe4+, and Br– ions. Relevant bond distances are Ta–Ta 2.9059(8), Ta–Cl 2.449(2), and Ta–O 2.22(2)Å, respectively.

ChemInform Abstract: RING SUBSTITUENT EFFECTS ON ACETOPHENONE DIMETHYL ACETAL FORMATION. 1. DUAL‐PARAMETER TREATMENT OF EQUILIBRIUM DATA IN METHANOL, WATER AND DODECANE

Chemischer InformationsdienstVolume 15, Issue 23 Article ChemInform Abstract: RING SUBSTITUENT EFFECTS ON ACETOPHENONE DIMETHYL ACETAL FORMATION. 1. DUAL-PARAMETER TREATMENT OF EQUILIBRIUM DATA IN METHANOL, WATER AND DODECANE J. TOULLEC, J. TOULLECSearch for more papers by this authorM. EL-ALAOUI, M. EL-ALAOUISearch for more papers by this authorP. KLEFFERT, P. KLEFFERTSearch for more papers by this author J. TOULLEC, J. TOULLECSearch for more papers by this authorM. EL-ALAOUI, M. EL-ALAOUISearch for more papers by this authorP. KLEFFERT, P. KLEFFERTSearch for more papers by this author First published: June 5, 1984 https://doi.org/10.1002/chin.198423100AboutPDF 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 onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume15, Issue23June 5, 1984 RelatedInformation

Methanol Intoxication

A unique opportunity presented itself for reviewing and comparing the results of two different methods of dialytic therapy for the treatment of methanol (methyl alcohol) poisoning. The group that was treated with hemodialysis initially had a faster fall in serum methanol level, regained consciousness faster, had a shorter hospital stay, and, most importantly, had no residual effects when compared with the group treated with peritoneal dialysis. In this group, one patient died and another was permanently blinded. Therefore, we believe that hemodialysis, when available, is the initial treatment of choice in methanol poisoning and should be used concomitantly with alkaline therapy and the administration of alcohol (ethanol, ethyl alcohol).

Folat-katalysierte elimination der ameisensäure bei methanolvergiftung

The elimination of formate as catalysed by folate has been investigated during the course of methanol poisoning. The speed of formate elimination varies for different species; the half life ( t 1 2 ) of formate is 12 min in rats and 32 min in rabbits. In contrast it is 55 min in man and 77 min in the dog. A reciprocal correlation exists between formate half life and folate concentrations in plasma as determined with S. faecalis and L. casei. Treatment of methanol poisoned dogs with amethopterin leads to a remarkable rise of formate concentrations both in plasma and urine. On the contrary, an almost complete lack of accumulation of formate in plasma and urine was observed after preventive application of folate. It is suggested that therapeutic doses of folic acid enable the organism to eliminate toxic formic acid at a sufficient speed. An optimal effect was obtained with 2.5 mg/kg for dogs. An explanation for this can be found in the increased concentration of reduced folate enzymes leading to a faster elimination of formate. The occurrence of a stimulation of folate dependent enzyme systems, e.g. dihydrofolate reductase, is also discussed.

The Treatment of Methanol Poisoning with Ethanol; With Report of Two Cases

The Treatment of Methanol Poisoning with Ethanol; With Report of Two Cases