Batch and column mode tests were carried out to evaluate the efficiency of boron and arsenic removal from geothermal water in Kyushu Island, Japan by an ion exchange method. The geothermal water contained 34.0 mg-B/L and 3.23 mg-As/L. The sorption tests were performed using boron selective ion exchange resins (Lewatit MK 51 and Diaion CRB 03) and arsenic selective ion exchange resins (Lewatit FO 36, ArsenX^np). The optimum concentration of resin for boron removal from geothermal water was determined as 5.0 g/L-geothermal water for both Lewatit MK 51 and Diaion CRB 03 resins. On the other hand, Diaion CRB 03 performed better than Lewatit MK 51 during the column-mode study. For arsenic removal, the optimum resin amount was found as 6.0 g/L-geothermal water for both Lewatit FO 36 and ArsenX^np resins. It was observed that Lewatit FO 36 was more effective than ArsenX^np for the removal of As from geothermal water.

A new solid phase extraction-high-performance liquid chromatography method with ultraviolet detection was developed and validated for the determination of three chlorogenic acids (5-O-caffeoylquinic, 3-O-caffeoylquinic and 4-O-caffeoylquinic acids) and six phenolic acids (caffeic, ferulic, sinapic, protocatechuic, p-hydroxybenzoic acid (PHBA) and vanillic acid (VA)) in coffee bean samples. Extraction was performed using hydrophilic–lipophilic balance cartridges. Separations were accomplished using a C₁₈ guard column (10 × 2.1 mm, 3 µm) and a C₁₈ analytical column (50 × 2.1 mm, 3 µm). o-Phosphoric acid solution (0.08%) and methanol/water/acetonitrile (85:10:5) solution were used as mobile phase with a gradient system. A UV detector was used at 325 nm for 5-O-caffeoylquinic, caffeic, 3-O-caffeoylquinic, 4-O-caffeoylquinic, ferulic, sinapic acids, and 215 nm for protocatechuic, PHBA and VA. Calibration equations and coefficients of determination were determined by least-squares method with weighting factor. Limits of detection and quantification were in the range of 0.15–0.69 and 0.46–2.09 mg/L, respectively. Precision and accuracy of the proposed method were investigated with coffee sample spiked at low, medium and high concentrations. The developed and validated method was applied for the determination of nine phenolic compounds in seven coffee bean samples from different origins with high accuracy and repeatability.