The effect of temperature and transmembrane pressure on the camel milk ultrafiltration performance: An optimization study

In this study, the effects of transmembrane pressure (TMP, 80-160 kPa) and temperature (T, 20-40 oC) were investigated on the camel milk ultrafiltration (UF) performance including pseudo-steady state permeate flux (JPSS), intrinsic membrane resistance (Rm), reversible fouling resistance (Rrf), irreversible fouling resistance (Rif), solutes rejection (protein (RP), lactose (RL), ash (RA) and total solids (RTS)) and minerals rejection (aluminum (RAl), iron (RFe), zinc (RZn), manganese (RMn), calcium (RCa), phosphorus (RPh), sodium (RNa), magnesium (RMg), and potassium (RK)). Based on the results, increasing TMP led to a significant increase in JPSS, Rrf, and RA while increasing T caused a significant increase in JPSS, Rrf, RL, RA, and the rejection of all minerals. Although the total fouling resistance (Rf) increased by increasing TMP and T, the share of Rrf was higher in high TMP and T compared to Rif. The results also showed that none of the linear, quadratic, and interaction effects of TMP and T on the Rm, RTS, and RP of the samples were significant. In general, camel milk solute rejections, e.g., RTS, RP, RL, RA, RAl, RFe, RZn, RMn, RCa, RPh, RNa, RMg, and RK were, on average, 51.03, 97.51, 4.73, 34.07, 99.05, 95.70, 90.64, 99.99, 46.09, 32.74, 20.44, 19.44, and 7.78%, respectively. Finally, optimum UF performance conditions in this research with the lowest Rrf, Rif, RL, and RA while the highest JPSS and RP were 135 kPa TMP and 35 oC T.