Abstract:
Aliphatic esters, R'COOR are produced by reacting the corresponding alcohol, ROH having carbon numbers of the alkyl groups, R′ and R, between 0 and 9 and 1 and 10, respectively, with molecular oxygen in the presence of a dual functional catalyst comprising metal on acidic solid support. In particular, the process is used advantageously for production of ethyl acetate by conversion of ethanol. The reaction mixture from the reactor is separated through azeotropic distillation to recover the ethyl acetate as product and the by-product, acetaldehyde and acetic acid which could be recycled for further reaction. The process is characterized by high conversion of ethanol, high selectivity and high yield for ethyl acetate and low waste stream generation. The preferred catalyst is Pd on zeolites which is active, selective, stable and regenerable.
Abstract:
Partial oxidation of crumb rubber derived from environmental hazardous waste tires yields surface treated crumb rubber which are used as blending stocks for making rubberized concrete with substantially improved mechanical strength as compared to the conventional rubberized concrete. The chemically more active rubber surface becomes hydrophilic, so it interacts with the hydrophilic surface of surrounding cement matrix much stronger. The mechanically improved rubberized concrete is more versatile than conventional rubberized concrete.
Abstract:
Partial oxidation of crumb rubber derived from environmental hazardous waste tires yields surface treated crumb rubber and a gas condensate which are used as blending stocks for making rubberized concrete with substantially improved mechanical strength as compared to the conventional rubberized concrete. The chemically more active rubber surface becomes hydrophilic, so it interacts with the hydrophilic surface of surrounding cement matrix much stronger. The gas condensate co-produced in the partial oxidation reactor consists of mainly active sulfur oxides (R—SOx—R) and serves as an excellent bonding agent to further enhance the bonding strength between the partially oxidized rubber particles and the cement mixes. The mechanically improved rubberized concrete is more versatile than conventional rubberized concrete.
Abstract:
Oxidation of liquid ethanol in the presence of excess liquid ethanol and a supported oxidation catalyst provides a one step process for production of ethyl acetate. The acetic acid produced in the oxidation is absorbed by the excess liquid ethanol, which esterifies to ethyl acetate. Ethyl acetate and water are removed from the process for separation of the ethyl acetate. The oxidation portion of process is preferred with a metallic oxidation catalyst on a hydrophobic support. The esterification portion of the process is preferred with an acidic solid ion exchange resin to promote the esterification. The process can be performed in series in separate steps, or preferably, in parallel in a single vessel, preferably a trickle bed reactor.
Abstract:
Non-basic and non-acidic homogeneous catalysts organo-metallic compound of the formula: M(OCH3)x wherein M is B, Na, Mg, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Al, Sn, Sb, Mo, Ag, and Cd and x is an integer from 2, 3 or 4 can catalyze transesterification of oils and fats having high free fatty acid content and with an acid number from 0.5 to 20, into biodiesel. B(OCH3)3 and Ge(OCH3)4, having low boiling points, are easily recovered from the biodiesel and glycerol phases and recycled for reuse. Continuous biodiesel production with the novel homogenous catalysts is achieved without the complicated and troublesome steps attendant with conventional processes using base or acid homogeneous catalyst. The high purity biodiesel is produced without acid-base neutralization, water wash, filtration, and solid disposal steps for removing the spent catalyst from the product streams associated with prior techniques.
Abstract:
Partial oxidation of crumb rubber derived from environmental hazardous waste tires yields surface treated crumb rubber and a gas condensate which are used as blending stocks for making rubberized concrete with substantially improved mechanical strength as compared to the conventional rubberized concrete. The chemically more active rubber surface becomes hydrophilic, so it interacts with the hydrophilic surface of surrounding cement matrix much stronger. The gas condensate co-produced in the partial oxidation reactor consists of mainly active sulfur oxides (R—SOx—R) and serves as an excellent bonding agent to further enhance the bonding strength between the partially oxidized rubber particles and the cement mixes. The mechanically improved rubberized concrete is more versatile than conventional rubberized concrete.
Abstract:
A continuous and regenerative process for removal and destruction of VOC from effluents is disclosed. The process employs two fixed bed reactors in series filled with adsorbent/catalyst. The VOC containing effluent is passed over the first reactor for adsorbing VOC, while the second reactor, which is loaded with VOC from the previous cycle is regenerated with part of the treated gas made up with an appropriate amount of air. Just before the VOC breakthrough occurs at the first reactor, the roles of the two reactors are switched. The process is characterized by simple design, high VOC removal efficiency, no external heat requirement and low operation cost.