Chapters authored
Development, Characterization, and Applications of Capsaicin Composite Nanofiltration Membranes
Biofouling in reverse osmosis (RO) membranes is a severe problem, causing a decrease in both permeate flux and salt rejection and increasing transmembrane pressure. Capsaicin extract inhibits bacterial growth and is therefore used in this study to prepare a thin-film composite membrane and membrane support. Four types of nanofiltration (NF) membranes were prepared by interfacial polymerization onto a porous support prepared by the phase inversion method. Membrane A was the control membrane with no capsaicin extract, membrane B contains capsaicin in the polyamide thin film, membrane C contains capsaicin in the porous support, and membrane D contains capsaicin in both the thin film and support layers. Three different salts (Na2SO4, MgSO4, and NaCl) were used at different concentrations (1000, 3000, and 5000 ppm) to test the performance of the membranes in terms of salt rejection and permeate flux. Membrane B showed the highest rejection for all the salts and concentrations tested. For 5000 ppm NaCl, the permeate flux for membrane B was 14.81% higher, and salt rejection was 19.6% higher than membrane A. Future work will evaluate the anti-biofouling properties of the membranes prepared with capsaicin, when exposed to seawater microorganisms.
Part of the book: Desalination and Water Treatment
Using Desalination to Improve Agricultural Yields: Success Cases in Mexico
Water scarcity is a global problem, motivating growth and development of new technologies for water treatment, reuse and desalination. For many arid regions in Mexico, especially in the northwest, agriculture is an important economic activity. The Yaqui Valley in Sonora, Mexico, faces problems related to aquifer overexploitation and saline intrusion, which have increased salt concentration in well water to 2000–9000 mg/L total dissolved solids (TDS) and led to soil salinization and low crop yields. This work evaluates the effect of TDS in irrigation water on crop yield. A 150 m3/d desalination plant was used, consisting of 12 SWC4B-MAX membrane modules, with 98% rejection and 75% recovery. Two crops were irrigated with control (4000 mg/L) and desalinated water (200 mg/L). Sorghum (Sorghum) had yields of 7.9 and 8.8 ton/ha, whereas tomatillo (Physalis philadelphica) had yields of 30.82 and 35.88 ton/ha, respectively. Evidently, the desalination process influences agricultural yields.
Part of the book: Desalination and Water Treatment