A process for continuous, on-demand production of dilute acrolein liquid on-site, at or near the point of acrolein injection, by the liquid dehydration of glycerol in an improved tubular reactor where non-aqueous glycerol is combined with a heteropolyacid catalyst, including silicotungstic acid, phosphotungstic acid, or phosphomolybdic acid. The acid catalyst is evenly dissolved and dispersed in the glycerol upstream of the reactor vessel. The reaction is conducted in a tubular reactor which is heated to an elevated reaction temperature. The dilute acrolein produced in the tubular reactor is directed downstream, optionally through a liquid-liquid heat exchanger and then an air-liquid heat exchanger to reduce temperature, and then diluted prior to being injected into sulfide contaminated systems (such as oil & gas water floods, water disposal systems, producing oil wells, and fuel oil storage) via a pressure conduit.

Methods for making acrylic acid, acrylic acid derivatives, or mixtures thereof by contacting a stream containing hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof with either an active catalyst containing an amorphous and partially-dehydrated phosphate salt or a precursor catalyst containing a crystalline phosphate salt in a reactor with a low corrosion rate are provided.

Methods for making acrylic acid, acrylic acid derivatives, or mixtures thereof by contacting a stream containing hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof with either an active catalyst containing an amorphous and partially-dehydrated phosphate salt or a precursor catalyst containing a crystalline phosphate salt in a reactor with a low corrosion rate are provided.

A photocatalytic filter including first photocatalytic particles each of which is a composite of an adsorbent and titanium apatite, second photocatalytic particles each of which is glass coated with titanium apatite, a light source configured to emit ultraviolet rays, and a container accommodating the first photocatalytic particles, the second photocatalytic particles, and the light source.

Hydrotreating catalysts are provided having one or more phosphorus components carried on a composite support of a titanium-loaded binder component and post-framework modified ultra-stable Y-type zeolite. The support comprises the titanium-loaded binder component and a post-framework modified ultra-stable Y-type (USY) zeolite in which a portion of aluminum atoms constituting a zeolite framework thereof is substituted with zirconium atoms and/or titanium atoms and/or hafnium atoms. The active components including the phosphorous active component and one or more hydrocracking metals active components loaded on the support.

Hydrotreating catalysts are provided having one or more phosphorus components carried on a composite support of a titanium-loaded binder component and post-framework modified ultra-stable Y-type zeolite. The support comprises the titanium-loaded binder component and a post-framework modified ultra-stable Y-type (USY) zeolite in which a portion of aluminum atoms constituting a zeolite framework thereof is substituted with zirconium atoms and/or titanium atoms and/or hafnium atoms. The active components including the phosphorous active component and one or more hydrocracking metals active components loaded on the support.

Methods of making hydrotreating catalysts are provided having one or more phosphorus components carried on a composite support of a titanium-loaded binder component and post-framework modified ultra-stable Y-type zeolite. The support comprises the titanium-loaded binder component and a post-framework modified ultra-stable Y-type (USY) zeolite. The active components including the phosphorous active component and one or more hydrocracking metals active components loaded on the support.

The present invention relates to the production of biodiesel and alkyl esters by the transesterification of triglyceride esters, with alcohols in heterogeneous phase in the presence of heterogeneous catalysts, with yields higher than 80%, at a temperature from 0 to 300? C., residence time from 20 minutes to 20 h, space velocity of 0.1 to 10 h.sup.?1, pressure of 25-100 kg/cm.sup.2 (24.5-98.07 bar), methanol/oil molar ratio of 10 to 40 and catalyst concentration of 0.001 to 20 weight % based on tri-, di- or monoglyceride. The method produces biodiesel and alkyl esters by transesterification of tri-, di- or mono-glycerides, from palm, jatropha, castor, soybean and sunflower oils, wherein the alcohoxyls R.sup.1O, R.sup.2O and R.sup.3O of the glycerides are C.sub.1 to C.sub.24 and a C.sub.1-C.sub.4 alcohol, such as methanol, in an alcohol:oil ratio from 3:1 to 50:1. The transesterification reaction produces biodiesel while avoiding loss of catalyst, contaminating liquid effluents and eliminating undesirable hydrolysis of triglycerides, diglycerides and monoglycerides into free fatty acids and saponification that generate soaps.

The present invention relates to: a catalyst for glycerin dehydration; a preparation method therefor; and an acrolein preparation method using the catalyst. According to one embodiment of the present invention, the catalyst is used in glycerin dehydration so as to exhibit high catalytic activity, a high yield and high acrolein selectivity, and has a characteristic in which carbon is not readily deposited, thereby having a long lifetime compared with that of a conventional catalyst.

Methods for making acrylic acid, acrylic acid derivatives, or mixtures thereof by contacting a stream containing hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof with either an active catalyst containing an amorphous and partially-dehydrated phosphate salt or a precursor catalyst containing a crystalline phosphate salt in a reactor with a low corrosion rate are provided.