A method for extracting an elemental metal from agricultural waste including collecting a sample of the waste and performing an electrochemical extraction on the waste to producing a metal precipitate and a byproduct. The method further including collecting the metal precipitate and byproduct produced via the electrochemical extraction for further reaction, recycling, sale, or reuse.

A method for extracting an elemental metal from agricultural waste including collecting a sample of the waste and performing an electrochemical extraction on the waste to producing a metal precipitate and a byproduct. The method further including collecting the metal precipitate and byproduct produced via the electrochemical extraction for further reaction, recycling, sale, or reuse.

A zero-power digital chemical analyzer can include a chemically-selective percolation switch. The chemically selected percolation switch can include a positive electrode and a negative electrode separated from the positive electrode by a gap. A binding agent can be located at binding sites in the gap. The binding agent can be selective for binding to a target chemical compound. The binding sites can be distributed in the gap so that target chemical molecules binding to the binding sites can form an electrically conductive pathway via a natural percolation phenomenon between the electrodes when the ambient concentration of the target chemical compound reaches a threshold concentration.

A zero-power digital chemical analyzer can include a chemically-selective percolation switch. The chemically selected percolation switch can include a positive electrode and a negative electrode separated from the positive electrode by a gap. A binding agent can be located at binding sites in the gap. The binding agent can be selective for binding to a target chemical compound. The binding sites can be distributed in the gap so that target chemical molecules binding to the binding sites can form an electrically conductive pathway via a natural percolation phenomenon between the electrodes when the ambient concentration of the target chemical compound reaches a threshold concentration.

A method for extracting an elemental metal from agricultural waste including collecting a sample of the waste and performing an electrochemical extraction on the waste to producing a metal precipitate and a byproduct. The method further including collecting the metal precipitate and byproduct produced via the electrochemical extraction for further reaction, recycling, sale, or reuse.

A method for extracting an elemental metal from agricultural waste including collecting a sample of the waste and performing an electrochemical extraction on the waste to producing a metal precipitate and a byproduct. The method further including collecting the metal precipitate and byproduct produced via the electrochemical extraction for further reaction, recycling, sale, or reuse.

A zero-power digital chemical analyzer can include a chemically-selective percolation switch. The chemically selected percolation switch can include a positive electrode and a negative electrode separated from the positive electrode by a gap. A binding agent can be located at binding sites in the gap. The binding agent can be selective for binding to a target chemical compound. The binding sites can be distributed in the gap so that target chemical molecules binding to the binding sites can form an electrically conductive pathway via a natural percolation phenomenon between the electrodes when the ambient concentration of the target chemical compound reaches a threshold concentration.

A zero-power digital chemical analyzer can include a chemically-selective percolation switch. The chemically selected percolation switch can include a positive electrode and a negative electrode separated from the positive electrode by a gap. A binding agent can be located at binding sites in the gap. The binding agent can be selective for binding to a target chemical compound. The binding sites can be distributed in the gap so that target chemical molecules binding to the binding sites can form an electrically conductive pathway via a natural percolation phenomenon between the electrodes when the ambient concentration of the target chemical compound reaches a threshold concentration.