Homogeneous Solid‐State Titanium Phosphate Potentiometric Sensor and its Application; Sorption of Iron (III) by Modified Chitosan in Two Modes of Operations

Abstract

A solid state iron (III) potentiometric sensor based on a pure tablet of titanium phosphate (TP) ion exchanger as sensitive membrane is elaborated. A homogeneous sensor prepared by this exchanger displays a useful analytical response with a super Nernestian cationic response (slope 22.5±1 mV/decade), excellent reproducibility and applicability over a wide range of iron (III) concentration (1×10⁻⁶ −1× 10⁻² mol l⁻¹). It also offers the advantages of fast response time (<1 min.), low cost, and simple construction. The proposed potentiometric sensor was successfully used in direct potentiometry as a low cost monitoring in sorption of iron (III) using modified chitosan in two modes of operations. Langmuir and Freundlich constants have been determined. In continuous flow system, the influences of varying parameters such as bed depth and solution flow rate have been studied. In a new approach (low cost monitoring/low cost treatment), the feasibility of the proposed potentiometric sensor in monitoring and the modified chitosan as sorbent in treatment of iron (III) from liquid waste streams were addressed.

Keywords:

• Homogeneous solid‐state
• potentiometric sensor
• iron (III) monitoring
• modified chitosan
• sorption