Abstract: Apparatus and methods for quickly and easily detecting trace amounts of metallic or non-metallic, electro-active substances, and in particular trace amounts of metals, such as lead in a portable, hand-held detector system with single potential control.

Abstract: Paired electrochemical synthesis reactions in which ethylene glycol is formed at the cathode of a membrane divided cell at high concentrations and current efficiencies, up to 99 percent. Simultaneously, a compatible process is also conducted at the anode of the same electrochemical cell by reacting indirectly generated anode products with organic substrates to form secondary products, such as polybasic acids. The process is especially advantageous in that such secondary products, where appropriate can be further reacted with the ethylene glycol prepared from the catholyte of the same cell to form useful tertiary products, especially polyesters like polyethylene terephthalate. Mole ratios of ethylene glycol and polybasic acid can be controlled through selective use of regeneratable redox reactant.