01567nas a2200229 4500008004100000022001400041245011700055210006900172260007100241300001400312490000600326520073200332653001301064653001801077653001901095653000901114653002801123653001201151100002301163700002901186856012201215 2013 eng d a2155-543500aEfficient, stable, and reusable silicoaluminophosphate for the one-pot production of furfural from hemicellulose0 aEfficient stable and reusable silicoaluminophosphate for the one a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT a2299-23030 v33 a

Development of stable, reusable, and water tolerant solid acid catalysts in the conversion of polysaccharides to give value-added chemicals is vital because catalysts are prone to undergo morphological changes during the reactions With the anticipation that silicoaluminophosphate (SAPO) catalysts will have higher hydrothermal stability, those were synthesized, characterized, and employed in a one-pot conversion of hemicellulose. SAPO-44 catalyst at 170 degrees C within 8 h could give 63% furfural yield with 88% mass balance and showed similar activity up to at least 8 catalytic cycles. The morphological studies revealed that SAPO catalysts having hydrophilic characteristics are stable under reaction conditions.

10afurfural10aHemicellulose10ahydrophilicity10aSAPO10awater-tolerant catalyst10azeolite1 aBhaumik, Prasenjit1 aDhepe, Paresh, Laxmikant uhttps://library.ncl.res.in/content/efficient-stable-and-reusable-silicoaluminophosphate-one-pot-production-furfural-001969nas a2200157 4500008004100000022001400041245008500055210006900140260011000209300001600319490000600335520130400341100002301645700002901668856011401697 2014 eng d a2046-206900aExceptionally high yields of furfural from assorted raw biomass over solid acids0 aExceptionally high yields of furfural from assorted raw biomass  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a26215-262210 v43 a

Development of stable and recyclable solid acid catalysts in the efficient valorisation of hemicellulose to yield C-5 sugars and furfural is vital to boost the prospects of using lignocelluloses for chemicals synthesis. Using an silicoaluminophosphate, namely SAPO-44, as a catalyst, an environmentally benign process of furfural synthesis from diversified real substrates (without any treatment or the need for separation of its components) is shown. In an efficient one-pot methodology, at 443 K and in the presence of a biphasic solvent system, selective conversions of hemicelluloses from raw biomass (bagasse, rice husk and wheat straw) to extraordinarily high yields of furfural of about 93% were attainable. Under similar reaction conditions, an 82% yield of furfural is also achievable directly from isolated hemicellulose within 10 h. Hydrophilic SAPO-44, having higher hydrothermal stability, showed similar activity for all the substrates for a minimum of up to 8 times in recycling runs. Various physicochemical characterizations (X-ray diffraction, thermogravimetric analysis-derivative thermogravimetry, temperature programmed desorption-NH3, N-2 sorption, solid-state nuclear magnetic resonance spectroscopy) of fresh and spent catalysts were used to improve SAPO-44 stability.

1 aBhaumik, Prasenjit1 aDhepe, Paresh, Laxmikant uhttps://library.ncl.res.in/content/exceptionally-high-yields-furfural-assorted-raw-biomass-over-solid-acids-001902nas a2200217 4500008004100000022001400041245009300055210006900148260007300217300001000290490000800300520114400308653001201452653001301464653001801477653001201495653001101507100002301518700002901541856011401570 2015 eng d a0920-586100aEffects of careful designing of SAPO-44 catalysts on the efficient synthesis of furfural0 aEffects of careful designing of SAPO44 catalysts on the efficien aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG a66-720 v2513 a

Considering the growing importance of furfural, it is necessary to develop a robust solid acid catalyst for the conversion of xylan (hemicelluloses) into furfural in a one-pot method. In this study, the effects of various components (Si, Al and P) and crystallization time on the preparation of acidic materials and their properties are extensively described. It is seen that with the increase in crystallization time (0, 48, 96, 176 h) during the synthesis of silicoaluminophosphate (SAPO-44), materials morphology changes from amorphous to AFI to CHA and the best activity for furfural synthesis (82%) from xylan was observed with SAPO-44 catalyst aged for 176 h. Since, acidity in the SAPO-44 is guided by the incorporation of Si in the ALPO framework, study on Si molar concentration (0.8, 1.0, 1.2, 1.4 and 1.6) in SAPO-44 was carried out and it was observed that SAPO-44 having 1.0 mole of Si content is the best catalyst for the xylan/xylose conversion to furfural. Catalyst structure-activity correlation is thoroughly defined with the help of several physico-chemical properties. (C) 2014 Elsevier B.V. All rights reserved.

10aBiomass10afurfural10aHemicellulose10aSAPO-4410aXylose1 aBhaumik, Prasenjit1 aDhepe, Paresh, Laxmikant uhttps://library.ncl.res.in/content/effects-careful-designing-sapo-44-catalysts-efficient-synthesis-furfural-0