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SUMMARY Exploitation of biomass wastes gives new hopes in the exploration of clean alternative fuel source such as hydrogen energy. The application of catalysts plays a major role in the process by enhancing the production of hydrogen via reformation and tar cracking reaction. However, certain drawbacks such as catalyst cost, deactivation, and regeneration remain unsolved in this process. In this study, we focused on potential Malaysian dolomite (Perlis) as the source of catalysts for palm frond gasification. The influences of mechanochemical treatment in three different media (air, ethanol, and water) on the catalytic activity of the material were analyzed. Important changes in the properties of the dolomite along with the high catalytic performance were noted as the results of the treatment. Notable changes in the dolomite structure and porosity were observed because of the impact of the treatment. Increment in the surface area of the catalysts boosts the H2 production and catalytic activity of dolomite. Moreover, substantial CO2 reduction was also observed during reaction as a result of the absorption capacity of treated dolomite. Thus, through mechanochemical treatment, the property of Malaysian dolomite is being greatly altered, which really suits as a potential catalyst for gasification. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The synthesis of carbon nanotubes (CNTs) by the chemical vapour deposition (CVD) method using natural calcite from Anadara granosa shells as the metal catalyst support was studied. Hexane and iron (Fe) were used as the carbon precursor and the active component of the catalyst, respectively. Response surface methodology (RSM) based on central composite design (CCD) was used to optimise the effect of total iron loading, the duration of reaction, and reaction temperature. The optimal conditions were total iron loading of 7.5%, a reaction time of 45 min, and a temperature of 850°C with a resulting carbon yield of 131.62%. Raman spectra, field-emission-scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analyses showed that the CNTs were of the multiwalled type (MWNTs). [ABSTRACT FROM AUTHOR]

The anion of hippuric acid, hippurate (Å), as an organic guest was intercalated into the interlayers of anionic clay, Zn/Al hydrotalcite-like or layered double hydroxides (LDH) host by direct co-precipitation method from aqueous solution for the formation of new nanohybrid compounds, Zn/Al-hippurate nanohybrids (ZAHs). Various Zn/Al molar ratios (R) = 3-5 and concentrations of HA (0.06-0.15 M) were used for the synthesis. ZAHs synthesized, using 0.15 M HA, was found to give well-ordered layered nanohybrid materials with an increase of the basal spacing to 19.6-21.0 Å compared to 8.8-9.0 Å in the LDHs. The increase in the basal spacing is due to the insertion of A- organic moiety into the LDH interlayers. Formation of the host-guest type of material was confirmed by XRD, FTIR, TGA/DTG and compositional analysis. The release of the intercalated guest was found to be tunable in a controlled manner by Zn/Al molar ratio and is governed by pseudo-second order kinetics. Thus, by varying the experimental conditions, the release property of the guest anion can be tailored as required. [ABSTRACT FROM AUTHOR]

The present work addresses the influence of microwave irradiation on undoped and doped vanadium phosphate catalysts. These catalysts were prepared via VOPO4 · 2H2O. The catalyst’s precursors‚ VOHPO4 · 0.5H2O were subjected to microwave irradiation and comparison was made with the conventional heating. The interaction of these complex materials with microwave and the addition of several doponts (Nb, Bi, Co, Mo) provide interesting improvements in catalyst preparation found to be a faster, develop higher surface area, higher activity and selectivity for the oxidation of n-butane to maleic anhydride. All the catalysts were characterized by using a combination of powder XRD, H2-TPR, BET surface area and SEM. [ABSTRACT FROM AUTHOR]

The present work developed porous carboxymethyl cellulose (CMC) carbon film from lignocellulosic based materials as supercapacitor electrode. Porous CMC carbon films of bamboo (B) and oil palm empty fruit bunch (O) were prepared through simple incipient wetness impregnation method followed by calcination process before incorporation with manganese oxide (Mn 2 O 3 ). The carbonization produced porous CMC carbon whereby CMCB exhibited higher surface area than CMCO. After Mn 2 O 3 incorporation, the crystallite size of CMCB and CMCO were calculated as 50.09 nm and 42.76 nm, respectively whereas Mn 2 O 3 /CMCB and Mn 2 O 3 /CMCO composite films were revealed to be 26.71 nm and 35.60 nm in size, respectively. Comparatively, the Mn 2 O 3 /CMCB composite film exhibited higher electrochemical performance which was 31.98 mF cm -2 as compared to 24.15 mF cm -2 by Mn 2 O 3 /CMCO composite film and both CMC carbon films with fairly stable cycling stability after 1000 charge-discharge cycles. Therefore, it can be highlighted that Mn 2 O 3 /CMC composite film as prepared from bamboo and oil palm fruit can potentially become the new electrode materials for supercapacitor application., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Layered double hydroxide of Mg-Al-carbonate system (MACH) was prepared and its heat-treated product (MACHT) was obtained by calcination at 500 degrees C. The resulting materials were used as an adsorbent for removal of color from synthetic textile wastewater (STW) and textile wastewater (TWW). Batch kinetic study showed that these materials are an efficient adsorbent for textile dye. The maximum adsorption capacities between 16 to 32 mg of dyes per g of adsorbent was obtained by fitting the adsorption data to the Langmuir adsorption Isotherm. It was found that the adsorption capacity of MACHT is higher than MACH.

Nanocomposites of Zn/Al-layered double hydroxide(anthraquinone-2,6-disulfonate) were synthesized by spontaneous direct assembly of inorganic and organic phases from aqueous solution. Powder X-ray diffraction patterns showed that a pure, single nanocomposite phase of good crystallinity was obtained using 1.0 M antraquinone-2,6-disulfonate ion (AQ26) and aging at 80 degrees C using conventional heating for 7 days or 0.5 h under microwave radiation, and these samples are denoted as ZAAN26C or ZAAN26MH, respectively. Zn/Al-nitrate-layered double hydroxide synthesized by a conventional method (ZANLC) showed a basal spacing of 8.3 A while both the nanocomposites showed 18.8 A as a result of AQ26 intercalation. FTIR study showed that the resulting nanocomposites are free from nitrate, the co-anion present in the mother liquor, indicating that only AQ26 is preferred during intercalation for the formation of the nanocomposite. The Brunauer, Emmet and Teller (BET) and micropore surface areas for ZAAN26C decreased relative to the ZANLC from 16.2 to 4.7 and 1.6 to 1.3 m2/g, respectively. These results indicate that AQ26 can be rapidly interdcalated in layered double hydroxide using microwave-aging resulting in a nanocomposite.