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• In-situ hydrothermal crystallization of clinoptilolite in TiO 2 dispersion. • Removal of CV dye by simultaneous effect of adsorption and photodegradation. • Adsorption and photodegradation kinetics of CV dye from water were proposed. The TiO 2 -supported clinoptilolite (TiO 2 /CP) was synthesized via in-situ hydrothermal crystallization of CP in TiO 2 dispersion medium to prepare an integrated photocatalytic adsorbent (IPCA). The micro-structural features and textural parameters of obtained TiO 2 /CP were characterized via X-ray diffraction, scanning electron microscope, high resolution transmission electron microscope, Fourier transform infrared spectroscopy, inductively coupled plasma-optical emission spectrometry, BET-isotherm, UV–vis spectrophotometer and Malvern zetasizer. The results showed a well dispersion and immobilization of anatase TiO 2 particles on the surface of leaf-like CP, and low pH value of point of zero charge (pH pzc) i.e. 2.20 (SCA3) revealed a highly negatively charged surface. The synthesized TiO 2 /CP were used as IPCAs for removal of crystal violet (CV) dye, showing a higher rate of adsorption (46 % removal in 10 min) followed by a relatively low rate of photocatalytic degradation (49 % degradation in 120 min). TiO 2 /CP (SCA3) significantly improved the removal efficiency: 95 % of CV dye was removed within 150 min during both adsorption and degradation using 0.2 g/L dose at pH 6, whereas only 59 and 31 % of the dye was removed by CP and TiO 2 alone respectively. Adsorption and degradation kinetics of CV dye were found to follow pseudo second and pseudo first order models, respectively, and the equilibrium adsorption results fitted Dubinin-Radushkevich model. The thermodynamic parameters (ΔG ads , ΔH ads , and ΔS ads) of adsorption process exhibited that adsorption is physical, spontaneous, exothermic and leads to higher entropy. [ABSTRACT FROM AUTHOR]