Methanol hybrid process

In simple experiments, particulate silica-supported CSPs having various cin-chonan carbamate selectors immobilized to the surface were employed in an enantioselective liquid-solid batch extraction process for the enantioselective enrichment of the weak binding enantiomer of amino acid derivatives in the liquid phase (methanol-0.1M ammonium acetate buffer pH 6) and the stronger binding enantiomer in the solid phase [64]. For example, when a CSP with the 6>-9-(tcrt-butylcarbamoyl)-6 -neopentoxy-cinchonidine selector was employed at an about 10-fold molar excess as related to the DNB-Leu selectand which was dissolved as a racemate in the liquid phase specified earlier, an enantiomeric excess of 89% could be measured in the supernatant after a single extraction step (i.e., a single equilibration step). This corresponds to an enantioselectivity factor of 17.7 (a-value in HPLC amounted to 31.7). Such a batch extraction method could serve as enrichment technique in hybrid processes such as in combination with, for example, crystallization. In the presented study, it was however used for screening of the enantiomer separation power of a series of CSPs. 

Although unexpected, the above reduction and methanol addition process does appear to be well established. For instance, the relevant product, 5.96, has been subject to X-ray diffraction analysis (Figure 5.5.5). The structure so obtained revealed that complex 5,96 is bowl shaped, and does, indeed, possess a meso-position that has been converted into a methoxy-bearing sp -hybridized center. Consistent with this structure and the addition of methanol it implies, is the observed loss of a Soret-like band in the visible spectrum of 5.96. Also consistent with it is the complex nature of the H NMR spectrum. Complex 5.96 actually exists as four stereoisomers (an enantiomeric set of diastereomers). These stereoisomers were found to interconvert readily in solution. This interconversion is slow on the NMR time scale. Thus, all species are seen in the NMR spectrum and this, as well as the loss in s)mimetry, contributes to the complexity of the H NMR spectrum. 

Lu, Y, et al.. Hybrid process of distillation side connected with pervaporation for separation of methanol/MTBE/C4 mixture. Desalination, 2002, 149(1 3) 81 87. 

Researchers studying polypeptide and polypeptide hybrid systems have also processed vesicles using two solvents. This method usually involves a common organic solvent that solubilizes both blocks and an aqueous solvent that solublizes only the hydrophilic block. The two solvents can be mixed with the polypeptide or polypeptide hybrid system at the same time or added sequentially. The choice of organic solvent depends heavily upon the properties of the polypeptide material, and commonly used solvents include dimethylformamide (DMF) [46, 59], methanol (MeOH) [49], dimethyl sulfoxide (DMSO) [50, 72], and tetrahydrofuran (THF) [44, 55]. Vesicles are usually formed when the organic solvent is slowly replaced with an aqueous solution via dialysis or removed through evaporation however, some vesicles have been reported to be present in the organic/aqueous mixture [49]. 

For last few years, extensive studies have been carried out on proton conducting inorganic/organic hybrid membranes prepared by sol-gel process for PEMFC operating with either hydrogen or methanol as a fuel [23]. A major motivation for this intense interest on hybrid membranes is high cost, limitation in cell operation temperature, and methanol cross-... 

Figure 8.2 Conceptual flowsheet of hybrid FutureGen/Methanol process.

Hybrisol [Hybrid solvent] A process for removing hydrogen sulfide from natural gases. Based on the Elf Activated MDEA process, but using added methanol to improve the removal of mercaptans and COS. 

In this paper, we have studied the solar methanol production by a solar-assisted coal gasification system, which will be able to start-up GCRED-system, from a point of fossil/solar energy hybridization using solar thermochemical process (STC). 

H-process, 487 HTI-process, 494-495 hybrid liquification, 512-513 indirect (ICTL), 486, 496-510 Kohleoel process, 490 -91 methanol-to-gasoline (MTG), 510-511 NEDOL process, 491 -94, 492 -94 single-stages processes, 495 -96 SMDS, 511-512 -to-methanol (CTM), 513-516 catalysts, 514... 

Hydrogenation of C02 occurs on a number of solid catalysts with Cu0/Zn0/Al203, methanol can be prepared but the equilibrium yields are less than 40%. The use of hybrid catalysts, containing solid acids, improves the yields by partial dehydration of the methanol to dimethyl ether.56 In situ IR spectroscopy has been used to identify catalytic intermediates in some processes. With Cu/ZrO/Si02, surface bound formate, gem-diolate and methoxide species could be observed before the final hydrolysis to methanol.57 Lithium salt-promoted Rh/Si02 catalysts increased the ethanol content of reduction mixtures from C02 as compared to the unpromoted reactions, but the main product was methane.58... 

Hydrocarbon synthesis, applying indirect processes and hybrid catalysts125,126 (first methanol is formed, then transformed to lower paraffins and olefins), either directly127,128 or using two-stage reactors126... 

Hybrid amide-thiourea hosts based on p-f-butylcalix[4]arene have been prepared with coloured p-nitrophenyl (11.37a) or fluorescent 1-napthyl substituents (11.37b). In DMSO the host binds strongly to dicarboxylates, particularly adipate (log/T= 2X10" M" ), accompanied by a colour change from yellow to red in the case of the nitrophenyl derivative. The colour change is reversible on addition of protic solvents such as methanol but is not observed for acetate or other basic, monovalent anions. While large chemical shift changes for the thiourea NH protons are observed for 11.37b (A5 up to ca. 3.5 ppm), the thiourea NH resonances for the more acidic 11.37a disappear due to deprotonation. The fluorescence of the napthyl substituent in 11.37b is significantly quenched in the absence of anions due to a PET process. Addition of dicarboxylates results in an increase of fluorescence emission intensity in a broad band from 410 - 600 nm. Addition of anion reduces the efficiency of the PET process. 

Design and analysis of combined distillation and PV processes for methanol/DMC, methanol/MTBE, Cross-linked PVA (PERVAP 1510) and plasma-polymerized PERVAP 1137 Hybrid PV + distillation has better economics particularly in terms of low premium energy requirement [201]... 

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