A method of recovering a rare earth metal can include incubating a bacterial consortium in the presence of a rare earth metal source comprising a rare earth metal and iron. The bacterial consortium can include an acid secreting bacterium, a heavy metal resistant bacterium, an iron-sequestering molecule secreting bacterium, and a rare earth metal sequestering bacterium. The method can further include: producing an acid using the acid secreting bacterium; leaching iron and the rare earth metal from the rare earth metal source using the acid; protecting the bacterial consortium from metal using the heavy metal resistant bacterium; sequestering iron using the iron-sequestering molecule secreting bacterium; and sequestering the rare earth metal using the rare earth metal sequestering bacterium

A method of recovering a rare earth metal can include incubating a bacterial consortium in the presence of a rare earth metal source comprising a rare earth metal and iron. The bacterial consortium can include an acid secreting bacterium, a heavy metal resistant bacterium, an iron-sequestering molecule secreting bacterium, and a rare earth metal sequestering bacterium. The method can further include: producing an acid using the acid secreting bacterium; leaching iron and the rare earth metal from the rare earth metal source using the acid; protecting the bacterial consortium from metal using the heavy metal resistant bacterium; sequestering iron using the iron-sequestering molecule secreting bacterium; and sequestering the rare earth metal using the rare earth metal sequestering bacterium

A method for supercritical fluid extraction of metal from a source, the method comprising: providing a reactor chamber; providing a source comprising a target metal; optionally, providing a chelating agent; providing a solvent; adding the source comprising the target metal, the chelating agent and the solvent into the reactor chamber; adjusting the temperature and pressure in the reactor chamber so that the solvent is heated and compressed above its critical temperature and pressure; optionally, providing mechanical agitation to the reactor chamber; recovering a chelate comprising the target metal.

The technical field of enzyme immobilization, and particularly, an organic-inorganic hybrid nanoflower and a preparation method thereof. The organic-inorganic hybrid nanoflower is a flower-like immobilized enzyme formed by self-assembly of a layered rare earth compound as an inorganic carrier and a biological enzyme as an organic component. The layered rare earth compound is Ln.sub.2(OH).sub.5NO.sub.3.nH.sub.2O, where Ln is one or more of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Y, and n=1.1-2.5. The biological enzyme is one or more of α-amylase, horseradish peroxidase, or laccase. A layered rare earth compound is used as the inorganic carrier for the organic biological enzyme to form the flower-like immobilized enzyme. The immobilized enzyme has better stability and higher catalytic performance when compared with a free enzyme.

The technical field of enzyme immobilization, and particularly, an organic-inorganic hybrid nanoflower and a preparation method thereof. The organic-inorganic hybrid nanoflower is a flower-like immobilized enzyme formed by self-assembly of a layered rare earth compound as an inorganic carrier and a biological enzyme as an organic component. The layered rare earth compound is Ln.sub.2(OH).sub.5NO.sub.3.nH.sub.2O, where Ln is one or more of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Y, and n=1.1-2.5. The biological enzyme is one or more of α-amylase, horseradish peroxidase, or laccase. A layered rare earth compound is used as the inorganic carrier for the organic biological enzyme to form the flower-like immobilized enzyme. The immobilized enzyme has better stability and higher catalytic performance when compared with a free enzyme.

A solution of acid deficient uranyl nitrate has a formula of UO.sub.2(OH).sub.y(NO.sub.3).sub.2-y, where y ranges from 0.1 to 0.5. The solution is prepared by placing U.sub.xO.sub.z in aqueous nitric acid to produce a uranium solution, wherein x is 1 to 3 and z is 2 to 8; placing the uranium solution under a pressure greater than atmospheric pressure in a sealed reaction chamber; and heating the uranium solution to a desired temperature of between 150 C. and 250 C. by applying microwave energy to the uranium solution. The uranium solution is maintained at the desired temperature under a pressure of from 5 atmospheres to 40 atmospheres for a hold time of 15 minutes to 6 hours to produce the desired acid deficient uranyl nitrate.

A solution of acid deficient uranyl nitrate has a formula of UO.sub.2(OH).sub.y(NO.sub.3).sub.2-y, where y ranges from 0.1 to 0.5. The solution is prepared by placing U.sub.xO.sub.z in aqueous nitric acid to produce a uranium solution, wherein x is 1 to 3 and z is 2 to 8; placing the uranium solution under a pressure greater than atmospheric pressure in a sealed reaction chamber; and heating the uranium solution to a desired temperature of between 150 C. and 250 C. by applying microwave energy to the uranium solution. The uranium solution is maintained at the desired temperature under a pressure of from 5 atmospheres to 40 atmospheres for a hold time of 15 minutes to 6 hours to produce the desired acid deficient uranyl nitrate.

A process of isolating samarium from a hydrophilic composition comprises nitrate ions, europium and samarium, by reducing europium(III) to europium(II) in this hydrophilic composition, and by extracting the samarium with a water-immiscible organic phase comprising an ionic liquid comprising nitrate anions.

A solution of acid deficient uranyl nitrate has a formula of UO.sub.2(OH).sub.y(NO.sub.3).sub.2-y, where y ranges from 0.1 to 0.5. The solution is prepared by placing U.sub.xO.sub.z in aqueous nitric acid to produce a uranium solution, wherein x is 1 to 3 and z is 2 to 8; placing the uranium solution under a pressure greater than atmospheric pressure in a sealed reaction chamber; and heating the uranium solution to a desired temperature of between 150 C. and 250 C. by applying microwave energy to the uranium solution. The uranium solution is maintained at the desired temperature under a pressure of from 5 atmospheres to 40 atmospheres for a hold time of 15 minutes to 6 hours to produce the desired acid deficient uranyl nitrate.

A solution of acid deficient uranyl nitrate has a formula of UO.sub.2(OH).sub.y(NO.sub.3).sub.2-y, where y ranges from 0.1 to 0.5. The solution is prepared by placing U.sub.xO.sub.z in aqueous nitric acid to produce a uranium solution, wherein x is 1 to 3 and z is 2 to 8; placing the uranium solution under a pressure greater than atmospheric pressure in a sealed reaction chamber; and heating the uranium solution to a desired temperature of between 150 C. and 250 C. by applying microwave energy to the uranium solution. The uranium solution is maintained at the desired temperature under a pressure of from 5 atmospheres to 40 atmospheres for a hold time of 15 minutes to 6 hours to produce the desired acid deficient uranyl nitrate.