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Ultrasonic sonication and microwave irradiation exhibited pronounced effects on crystalline Mn(II) carbonate catalyzed biodiesel production using watermelon (Citrullus vulgaris) seed oil and alcohol (fibrous flesh) as exclusive green feedstock. Both ingredients, alcohol and oil, necessary for biodiesel production are extracted from watermelon fruit. Mn(II) carbonate and watermelon fruit, which are used for transesterification, are inexpensive, easily available and environmentally safe. The reactions occurred smoothly under conventional conditions and afforded good product yields. However, microwave assisted and ultrasonically assisted reactions exhibited highly significant reduction in reaction times with a trend: microwave assisted (35 min) << ultrasonically assisted (2.0 h) << conventional (8.0 h). The whole exercise is operationally simple, environmentally safe, energy saving, time saving and green, which fits well into the green chemical principles of Anastas and Warner.

Zeolite Y was found to be an efficient catalyst for a facile nitration of aromatic compounds with acetonitrile as the solvent in the presence of small amounts of HNO3 at room temperature. The reactions afforded mono-nitro derivatives of aromatic compounds in about three hours under stirred conditions with high yields and regioselectivity. The reaction times drastically reduced to about 20 min under sonication and to about 20 s under microwave irradiation. Zeolite is recovered after completion of the reaction and recycled for three to four times without any problem. The approach is particularly appropriate for the conversion of unsaturated cinnamic acids into nitrostyrenes.

Thiocyanation of various aromatic and heteroaromatic compounds has been studied using Zeolite H-SDUSY Powder (CBV720) as catalyst and ammonium thiocyanate (NH4SCN) as thiocyanation reagent in aceto...

Prussian blue triggered transesterification of ethylacetoacetate with various alcohols underwent efficiently. The reaction is mild, eco-friendly, and selective with good yields. The proposed reaction pathway depicts the formation of an intermediate by the interaction of β-ketoesters with catalytic site of the Prussian blue, followed by nucleophilic attack of the alcohol at the electrophilic center followed by successive elimination of the proton to give the product. Observed longer reaction times under conventional conditions reduced amazingly under sonication and microwave irradiation followed enhanced yield of products.

Transesterification of β-ketoesters with different alcohols has been studied under conventional and unconventional conditions using the simple desktop chemical cesium carbonate as catalyst. These methods enabled transesterification of β-ketoesters in good yields with dramatic rate acceleration and reduced reaction times. The procedures which used unconventional methods, for example sonication and microwave irradiation, are highly promising compared with conventional procedures.

Transesterification of β-ketoesters with various alcohols has been studied under conventional and non-conventional conditions using desktop chemicals such as Mn(II) salts as catalysts. These methods offered transesterification of β-ketoesters in good yields with dramatic rate accelerations and reduced reaction times. The developed protocols under nonconventional methods such as sonication and microwave irradiation are highly promising compared with the existing procedures.

Since conventional conditions require reaction times of 16-24h, the transformation of β-keto ester (I) is investigated under ultrasound or microwave conditions where the latter afford optimal results concerning the time.

The rate of interparticle vanadium transfer in FCC catalysts as a function of the degree of oxidation of the steaming environment has been determined. The rate of interparticle vanadium transfer is low when the atmosphere in the steamer is reducing, but increases dramatically as the mole % excess oxygen becomes greater than zero. High rate of vanadium transfer is accompanied by a greater loss of surface area and catalytic activity. XPS measurements show that the oxidation state of vanadium increases from +3 when the steamer atmosphere is reducing to +5 when the % excess oxygen is greater than zero. Surface vanadium concentration follows a similar trend. In addition, data from a commercial resid FCCU operating in a partial burn were analyzed. The results of the analyses show that defining a partial burn operation with the flue gas CO/CO 2 ratio is not adequate for characterizing the vanadium oxidation state. Carbon on regenerated catalyst is a better marker for the vanadium oxidation state in the regenerator.